Lu Jiong
Degree: PhD
Position: Associate Professor
Affiliation: NUS – Department of Chemistry
Research Type: Experiment
Office: MD1-14-03F
Email: chmluj@nus.edu.sg
Contact: (65) 6516 2683
Website: https://www.chemistry.nus.edu.sg/people/academic_staff/LuJiong.htm
Research Interests:
Atomic-Scale Microscopy and Devices
2D Materials Synthesis
CA2DM Publications:
2024 |
Lyu, Pin; Wang, Ziying; Guo, Na; Su, Jie; Li, Jing; Qi, Dongchen; Xi, Shibo; Lin, Huihui; Zhang, Qihan; Pennycook, Stephen J; Chen, Jingsheng; Zhao, Xiaoxu; Zhang, Chun; Loh, Kian Ping; Lu, Jiong Air-Stable Wafer-Scale Ferromagnetic Metallo-Carbon Nitride Monolayer Journal Article JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 146 (30), pp. 20604-20614, 2024, ISSN: 0002-7863. @article{ISI:001272808300001, title = {Air-Stable Wafer-Scale Ferromagnetic Metallo-Carbon Nitride Monolayer}, author = {Pin Lyu and Ziying Wang and Na Guo and Jie Su and Jing Li and Dongchen Qi and Shibo Xi and Huihui Lin and Qihan Zhang and Stephen J Pennycook and Jingsheng Chen and Xiaoxu Zhao and Chun Zhang and Kian Ping Loh and Jiong Lu}, doi = {10.1021/jacs.4c02160}, times_cited = {0}, issn = {0002-7863}, year = {2024}, date = {2024-07-18}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {146}, number = {30}, pages = {20604-20614}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {The pursuit of robust, long-range magnetic ordering in two-dimensional (2D) materials holds immense promise for driving technological advances. However, achieving this goal remains a grand challenge due to enhanced quantum and thermal fluctuations as well as chemical instability in the 2D limit. While magnetic ordering has been realized in atomically thin flakes of transition metal chalcogenides and metal halides, these materials often suffer from air instability. In contrast, 2D carbon-based materials are stable enough, yet the challenge lies in creating a high density of local magnetic moments and controlling their long-range magnetic ordering. Here, we report a novel wafer-scale synthesis of an air-stable metallo-carbon nitride monolayer (MCN, denoted as MN4/CNx), featuring ultradense single magnetic atoms and exhibiting robust room-temperature ferromagnetism. Under low-pressure chemical vapor deposition conditions, thermal dehydrogenation and polymerization of metal phthalocyanine (MPc) on copper foil at elevated temperature generate a substantial number of nitrogen coordination sites for anchoring magnetic single atoms in monolayer MN4/CNx (where M = Fe, Co, and Ni). The incorporation of densely populating MN4 sites into monolayer MCN networks leads to robust ferromagnetism up to room temperature, enabling the observation of anomalous Hall effects with excellent chemical stability. Detailed electronic structure calculations indicate that the presence of high-density metal sites results in the emergence of spin-split d-bands near the Fermi level, causing a favorable long-range ferromagnetic exchange coupling through direct exchange interactions. Our work demonstrates a novel synthesis approach for wafer-scale MCN monolayers with robust room-temperature ferromagnetism and may shed light on practical electronic and spintronic applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The pursuit of robust, long-range magnetic ordering in two-dimensional (2D) materials holds immense promise for driving technological advances. However, achieving this goal remains a grand challenge due to enhanced quantum and thermal fluctuations as well as chemical instability in the 2D limit. While magnetic ordering has been realized in atomically thin flakes of transition metal chalcogenides and metal halides, these materials often suffer from air instability. In contrast, 2D carbon-based materials are stable enough, yet the challenge lies in creating a high density of local magnetic moments and controlling their long-range magnetic ordering. Here, we report a novel wafer-scale synthesis of an air-stable metallo-carbon nitride monolayer (MCN, denoted as MN4/CNx), featuring ultradense single magnetic atoms and exhibiting robust room-temperature ferromagnetism. Under low-pressure chemical vapor deposition conditions, thermal dehydrogenation and polymerization of metal phthalocyanine (MPc) on copper foil at elevated temperature generate a substantial number of nitrogen coordination sites for anchoring magnetic single atoms in monolayer MN4/CNx (where M = Fe, Co, and Ni). The incorporation of densely populating MN4 sites into monolayer MCN networks leads to robust ferromagnetism up to room temperature, enabling the observation of anomalous Hall effects with excellent chemical stability. Detailed electronic structure calculations indicate that the presence of high-density metal sites results in the emergence of spin-split d-bands near the Fermi level, causing a favorable long-range ferromagnetic exchange coupling through direct exchange interactions. Our work demonstrates a novel synthesis approach for wafer-scale MCN monolayers with robust room-temperature ferromagnetism and may shed light on practical electronic and spintronic applications. |
Qiu, Zhizhan; Han, Yixuan; Noori, Keian; Chen, Zhaolong; Kashchenko, Mikhail; Lin, Li; Olsen, Thomas; Li, Jing; Fang, Hanyan; Lyu, Pin; Telychko, Mykola; Gu, Xingyu; Adam, Shaffique; Quek, Su Ying; Rodin, Aleksandr; Neto, Castro A H; Novoselov, Kostya S; Lu, Jiong Evidence for electron-hole crystals in a Mott insulator Journal Article NATURE MATERIALS, 23 (8), 2024, ISSN: 1476-1122. @article{ISI:001237790900002, title = {Evidence for electron-hole crystals in a Mott insulator}, author = {Zhizhan Qiu and Yixuan Han and Keian Noori and Zhaolong Chen and Mikhail Kashchenko and Li Lin and Thomas Olsen and Jing Li and Hanyan Fang and Pin Lyu and Mykola Telychko and Xingyu Gu and Shaffique Adam and Su Ying Quek and Aleksandr Rodin and Castro A H Neto and Kostya S Novoselov and Jiong Lu}, doi = {10.1038/s41563-024-01910-3}, times_cited = {2}, issn = {1476-1122}, year = {2024}, date = {2024-06-03}, journal = {NATURE MATERIALS}, volume = {23}, number = {8}, publisher = {NATURE PORTFOLIO}, address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY}, abstract = {The coexistence of correlated electron and hole crystals enables the realization of quantum excitonic states, capable of hosting counterflow superfluidity and topological orders with long-range quantum entanglement. Here we report evidence for imbalanced electron-hole crystals in a doped Mott insulator, namely, alpha-RuCl3, through gate-tunable non-invasive van der Waals doping from graphene. Real-space imaging via scanning tunnelling microscopy reveals two distinct charge orderings at the lower and upper Hubbard band energies, whose origin is attributed to the correlation-driven honeycomb hole crystal composed of hole-rich Ru sites and rotational-symmetry-breaking paired electron crystal composed of electron-rich Ru-Ru bonds, respectively. Moreover, a gate-induced transition of electron-hole crystals is directly visualized, further corroborating their nature as correlation-driven charge crystals. The realization and atom-resolved visualization of imbalanced electron-hole crystals in a doped Mott insulator opens new doors in the search for correlated bosonic states within strongly correlated materials.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The coexistence of correlated electron and hole crystals enables the realization of quantum excitonic states, capable of hosting counterflow superfluidity and topological orders with long-range quantum entanglement. Here we report evidence for imbalanced electron-hole crystals in a doped Mott insulator, namely, alpha-RuCl3, through gate-tunable non-invasive van der Waals doping from graphene. Real-space imaging via scanning tunnelling microscopy reveals two distinct charge orderings at the lower and upper Hubbard band energies, whose origin is attributed to the correlation-driven honeycomb hole crystal composed of hole-rich Ru sites and rotational-symmetry-breaking paired electron crystal composed of electron-rich Ru-Ru bonds, respectively. Moreover, a gate-induced transition of electron-hole crystals is directly visualized, further corroborating their nature as correlation-driven charge crystals. The realization and atom-resolved visualization of imbalanced electron-hole crystals in a doped Mott insulator opens new doors in the search for correlated bosonic states within strongly correlated materials. |
Rossi, Kevin; Ruiz-Ferrando, Andrea; Akl, Dario Faust; Abalos, Victor Gimenez; Heras-Domingo, Javier; Graux, Romain; Hai, Xiao; Lu, Jiong; Garcia-Gasulla, Dario; Lopez, Nuria; Perez-Ramirez, Javier; Mitchell, Sharon Quantitative Description of Metal Center Organization and Interactions in Single-Atom Catalysts (Adv. Mater. 5/2024) Journal Article ADVANCED MATERIALS, 36 (5), 2024, ISSN: 0935-9648. @article{ISI:001151799000052, title = {Quantitative Description of Metal Center Organization and Interactions in Single-Atom Catalysts (Adv. Mater. 5/2024)}, author = {Kevin Rossi and Andrea Ruiz-Ferrando and Dario Faust Akl and Victor Gimenez Abalos and Javier Heras-Domingo and Romain Graux and Xiao Hai and Jiong Lu and Dario Garcia-Gasulla and Nuria Lopez and Javier Perez-Ramirez and Sharon Mitchell}, doi = {10.1002/adma.202470038}, times_cited = {6}, issn = {0935-9648}, year = {2024}, date = {2024-02-01}, journal = {ADVANCED MATERIALS}, volume = {36}, number = {5}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
2023 |
Rossi, Kevin; Ruiz-Ferrando, Andrea; Akl, Dario Faust; Abalos, Victor Gimenez; HerasDomingo, Javier; Graux, Romain; Hai, Xiao; Lu, Jiong; Garcia-Gasulla, Dario; Lopez, Nuria; Perez-Ramirez, Javier; Mitchell, Sharon Quantitative Description of Metal Center Organization and Interactions in Single-Atom Catalysts Journal Article ADVANCED MATERIALS, 2023, ISSN: 0935-9648. @article{ISI:001118482300001, title = {Quantitative Description of Metal Center Organization and Interactions in Single-Atom Catalysts}, author = {Kevin Rossi and Andrea Ruiz-Ferrando and Dario Faust Akl and Victor Gimenez Abalos and Javier HerasDomingo and Romain Graux and Xiao Hai and Jiong Lu and Dario Garcia-Gasulla and Nuria Lopez and Javier Perez-Ramirez and Sharon Mitchell}, doi = {10.1002/adma.202307991}, times_cited = {5}, issn = {0935-9648}, year = {2023}, date = {2023-12-05}, journal = {ADVANCED MATERIALS}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Ultra-high-density single-atom catalysts (UHD-SACs) present unique opportunities for harnessing cooperative effects between neighboring metal centers. However, the lack of tools to establish correlations between the density, types, and arrangements of isolated metal atoms and the support surface properties hinders efforts to engineer advanced material architectures. Here, this work precisely describes the metal center organization in various mono- and multimetallic UHD-SACs based on nitrogen-doped carbon (NC) supports by coupling transmission electron microscopy with tailored machine-learning methods (released as a user-friendly web app) and density functional theory simulations. This approach quantifies the non-negligible presence of multimers with increasing atom density, characterizes the size and shape of these low-nuclearity clusters, and identifies surface atom density criteria to ensure isolation. Further, it provides previously inaccessible experimental insights into coordination site arrangements in the NC host, uncovering a repulsive interaction that influences the disordered distribution of metal centers in UHD-SACs. This observation holds in multimetallic systems, where chemically-specific analysis quantifies the degree of intermixing. These fundamental insights into the materials chemistry of single-atom catalysts are crucial for designing catalytic systems with superior reactivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Ultra-high-density single-atom catalysts (UHD-SACs) present unique opportunities for harnessing cooperative effects between neighboring metal centers. However, the lack of tools to establish correlations between the density, types, and arrangements of isolated metal atoms and the support surface properties hinders efforts to engineer advanced material architectures. Here, this work precisely describes the metal center organization in various mono- and multimetallic UHD-SACs based on nitrogen-doped carbon (NC) supports by coupling transmission electron microscopy with tailored machine-learning methods (released as a user-friendly web app) and density functional theory simulations. This approach quantifies the non-negligible presence of multimers with increasing atom density, characterizes the size and shape of these low-nuclearity clusters, and identifies surface atom density criteria to ensure isolation. Further, it provides previously inaccessible experimental insights into coordination site arrangements in the NC host, uncovering a repulsive interaction that influences the disordered distribution of metal centers in UHD-SACs. This observation holds in multimetallic systems, where chemically-specific analysis quantifies the degree of intermixing. These fundamental insights into the materials chemistry of single-atom catalysts are crucial for designing catalytic systems with superior reactivity. |
Wang, Wenhui; Erofeev, Ivan; He, Ya; Yang, Fangqi; Yan, Hongwei; Lu, Jiong; Mirsaidov, Utkur Direct Observation of Hollow Bimetallic Nanoparticle Formation through Galvanic Replacement and Etching Reactions Journal Article NANO LETTERS, 23 (23), pp. 10725-10730, 2023, ISSN: 1530-6984. @article{ISI:001125314300001, title = {Direct Observation of Hollow Bimetallic Nanoparticle Formation through Galvanic Replacement and Etching Reactions}, author = {Wenhui Wang and Ivan Erofeev and Ya He and Fangqi Yang and Hongwei Yan and Jiong Lu and Utkur Mirsaidov}, doi = {10.1021/acs.nanolett.3c02575}, times_cited = {2}, issn = {1530-6984}, year = {2023}, date = {2023-11-21}, journal = {NANO LETTERS}, volume = {23}, number = {23}, pages = {10725-10730}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {Hollow bimetallic nanoparticles (NPs) formed from metal oxide NP templates are widely used catalysts for hydrogen evolution and CO2 reduction reactions. Despite their importance in catalysis, the details of how these NPs form on the NP templates remain unclear. Here, using in situ liquid-phase transmission electron microscopy (TEM) imaging, we describe the conversion of Cu2O template NPs to hollow PdCu NPs. Our observations show that a polycrystalline PdCu shell forms on the surface of the template via a galvanic replacement reaction while the template undergoes anisotropic etching. This study provides important insights into the synthesis of hollow metallic nanostructures from metal oxide templates.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hollow bimetallic nanoparticles (NPs) formed from metal oxide NP templates are widely used catalysts for hydrogen evolution and CO2 reduction reactions. Despite their importance in catalysis, the details of how these NPs form on the NP templates remain unclear. Here, using in situ liquid-phase transmission electron microscopy (TEM) imaging, we describe the conversion of Cu2O template NPs to hollow PdCu NPs. Our observations show that a polycrystalline PdCu shell forms on the surface of the template via a galvanic replacement reaction while the template undergoes anisotropic etching. This study provides important insights into the synthesis of hollow metallic nanostructures from metal oxide templates. |
Fang, Hanyan; Mahalingam, Harshitra; Li, Xinzhe; Han, Xu; Qiu, Zhizhan; Han, Yixuan; Noori, Keian; Dulal, Dikshant; Chen, Hongfei; Lyu, Pin; Yang, Tianhao; Li, Jing; Su, Chenliang; Chen, Wei; Cai, Yongqing; Neto, Castro A H; Novoselov, Kostya S; Rodin, Aleksandr; Lu, Jiong Atomically precise vacancy-assembled quantum antidots Journal Article 17 NATURE NANOTECHNOLOGY, 18 (12), 2023, ISSN: 1748-3387. @article{ISI:001062548200002, title = {Atomically precise vacancy-assembled quantum antidots}, author = {Hanyan Fang and Harshitra Mahalingam and Xinzhe Li and Xu Han and Zhizhan Qiu and Yixuan Han and Keian Noori and Dikshant Dulal and Hongfei Chen and Pin Lyu and Tianhao Yang and Jing Li and Chenliang Su and Wei Chen and Yongqing Cai and Castro A H Neto and Kostya S Novoselov and Aleksandr Rodin and Jiong Lu}, doi = {10.1038/s41565-023-01495-z}, times_cited = {17}, issn = {1748-3387}, year = {2023}, date = {2023-08-31}, journal = {NATURE NANOTECHNOLOGY}, volume = {18}, number = {12}, publisher = {NATURE PORTFOLIO}, address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY}, abstract = {Patterning antidots, which are regions of potential hills that repel electrons, into well-defined antidot lattices creates fascinating artificial periodic structures, leading to anomalous transport properties and exotic quantum phenomena in two-dimensional systems. Although nanolithography has brought conventional antidots from the semiclassical regime to the quantum regime, achieving precise control over the size of each antidot and its spatial period at the atomic scale has remained challenging. However, attaining such control opens the door to a new paradigm, enabling the creation of quantum antidots with discrete quantum hole states, which, in turn, offer a fertile platform to explore novel quantum phenomena and hot electron dynamics in previously inaccessible regimes. Here we report an atomically precise bottom-up fabrication of a series of atomic-scale quantum antidots through a thermal-induced assembly of a chalcogenide single vacancy in PtTe2. Such quantum antidots consist of highly ordered single-vacancy lattices, spaced by a single Te atom, reaching the ultimate downscaling limit of antidot lattices. Increasing the number of single vacancies in quantum antidots strengthens the cumulative repulsive potential and consequently enhances the collective interference of multiple-pocket scattered quasiparticles inside quantum antidots, creating multilevel quantum hole states with a tunable gap from the telecom to far-infrared regime. Moreover, precisely engineered quantum hole states of quantum antidots are geometry protected and thus survive on oxygen substitutional doping. Therefore, single-vacancy-assembled quantum antidots exhibit unprecedented robustness and property tunability, positioning them as highly promising candidates for advancing quantum information and photocatalysis technologies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Patterning antidots, which are regions of potential hills that repel electrons, into well-defined antidot lattices creates fascinating artificial periodic structures, leading to anomalous transport properties and exotic quantum phenomena in two-dimensional systems. Although nanolithography has brought conventional antidots from the semiclassical regime to the quantum regime, achieving precise control over the size of each antidot and its spatial period at the atomic scale has remained challenging. However, attaining such control opens the door to a new paradigm, enabling the creation of quantum antidots with discrete quantum hole states, which, in turn, offer a fertile platform to explore novel quantum phenomena and hot electron dynamics in previously inaccessible regimes. Here we report an atomically precise bottom-up fabrication of a series of atomic-scale quantum antidots through a thermal-induced assembly of a chalcogenide single vacancy in PtTe2. Such quantum antidots consist of highly ordered single-vacancy lattices, spaced by a single Te atom, reaching the ultimate downscaling limit of antidot lattices. Increasing the number of single vacancies in quantum antidots strengthens the cumulative repulsive potential and consequently enhances the collective interference of multiple-pocket scattered quasiparticles inside quantum antidots, creating multilevel quantum hole states with a tunable gap from the telecom to far-infrared regime. Moreover, precisely engineered quantum hole states of quantum antidots are geometry protected and thus survive on oxygen substitutional doping. Therefore, single-vacancy-assembled quantum antidots exhibit unprecedented robustness and property tunability, positioning them as highly promising candidates for advancing quantum information and photocatalysis technologies. |
Yang, Huimin; Xi, Shibo; Guo, Na; Wang, Mu; Liu, Lingmei; Lyu, Pin; Yu, Xiaolong; Li, Jing; Xu, Haomin; Hai, Xiao; Li, Zejun; Li, Xinzhe; Sun, Tao; Zhao, Xiaoxu; Han, Yu; Yu, Wei; Wu, Jie; Zhang, Chun; Fei, Honghan; Koh, Ming Joo; Lu, Jiong Catalytically active atomically thin cuprate with periodic Cu single sites Journal Article NATIONAL SCIENCE REVIEW, 10 (1), 2023, ISSN: 2095-5138. @article{ISI:000943284400001, title = {Catalytically active atomically thin cuprate with periodic Cu single sites}, author = {Huimin Yang and Shibo Xi and Na Guo and Mu Wang and Lingmei Liu and Pin Lyu and Xiaolong Yu and Jing Li and Haomin Xu and Xiao Hai and Zejun Li and Xinzhe Li and Tao Sun and Xiaoxu Zhao and Yu Han and Wei Yu and Jie Wu and Chun Zhang and Honghan Fei and Ming Joo Koh and Jiong Lu}, doi = {10.1093/nsr/nwac100}, times_cited = {5}, issn = {2095-5138}, year = {2023}, date = {2023-03-03}, journal = {NATIONAL SCIENCE REVIEW}, volume = {10}, number = {1}, publisher = {OXFORD UNIV PRESS}, address = {GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND}, abstract = {A ligand exchange strategy exfoliates bulk cuprate crystals into atomically thin 2D cuprate layers with periodic unsaturated copper single sites, which are found to promote efficient oxidative Chan-Lam coupling.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A ligand exchange strategy exfoliates bulk cuprate crystals into atomically thin 2D cuprate layers with periodic unsaturated copper single sites, which are found to promote efficient oxidative Chan-Lam coupling. |
2022 |
Telychko, Mykola; Noori, Keian; Biswas, Hillol; Dulal, Dikshant; Chen, Zhaolong; Lyu, Pin; Li, Jing; Tsai, Hsin-Zon; Fang, Hanyan; Qiu, Zhizhan; Yap, Zhun Wai; Watanabe, Kenji; Taniguchi, Takashi; Wu, Jing; Loh, Kian Ping; Crommie, Michael F; Rodin, Aleksandr; Lu, Jiong Gate-Tunable Resonance State and Screening Effects for Proton-Like Atomic Charge in Graphene Journal Article NANO LETTERS, 2022, ISSN: 1530-6984. @article{ISI:000871063800001, title = {Gate-Tunable Resonance State and Screening Effects for Proton-Like Atomic Charge in Graphene}, author = {Mykola Telychko and Keian Noori and Hillol Biswas and Dikshant Dulal and Zhaolong Chen and Pin Lyu and Jing Li and Hsin-Zon Tsai and Hanyan Fang and Zhizhan Qiu and Zhun Wai Yap and Kenji Watanabe and Takashi Taniguchi and Jing Wu and Kian Ping Loh and Michael F Crommie and Aleksandr Rodin and Jiong Lu}, doi = {10.1021/acs.nanolett.2c02235}, times_cited = {8}, issn = {1530-6984}, year = {2022}, date = {2022-10-10}, journal = {NANO LETTERS}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {The ability to create a robust and well-defined artificial atomic charge in graphene and understand its carrier dependent electronic properties represents an important goal toward the development of graphene-based quantum devices. Herein, we devise a new pathway toward the atomically precise embodiment of point charges into a graphene lattice by posterior (N) ion implantation into a back-gated graphene device. The N dopant behaves as an in-plane proton-like charge manifested by formation of the characteristic resonance state in the conduction band. Scanning tunneling spectroscopy measurements at varied charge carrier densities reveal a giant energetic renormalization of the resonance state up to 220 meV with respect to the Dirac point, accompanied by the observation of gate-tunable long-range screening effects close to individual N dopants. Joint density functional theory and tight-binding calculations with modified perturbation potential corroborate experimental findings and highlight the short-range character of N-induced perturbation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ability to create a robust and well-defined artificial atomic charge in graphene and understand its carrier dependent electronic properties represents an important goal toward the development of graphene-based quantum devices. Herein, we devise a new pathway toward the atomically precise embodiment of point charges into a graphene lattice by posterior (N) ion implantation into a back-gated graphene device. The N dopant behaves as an in-plane proton-like charge manifested by formation of the characteristic resonance state in the conduction band. Scanning tunneling spectroscopy measurements at varied charge carrier densities reveal a giant energetic renormalization of the resonance state up to 220 meV with respect to the Dirac point, accompanied by the observation of gate-tunable long-range screening effects close to individual N dopants. Joint density functional theory and tight-binding calculations with modified perturbation potential corroborate experimental findings and highlight the short-range character of N-induced perturbation. |
Fang, Hanyan; Gallardo, Aurelio; Dulal, Dikshant; Qiu, Zhizhan; Su, Jie; Telychko, Mykola; Mahalingam, Harshitra; Lyu, Pin; Han, Yixuan; Zheng, Yi; Cai, Yongqing; Rodin, Aleksandr; Jelinek, Pavel; Lu, Jiong Electronic Self-Passivation of Single Vacancy in Black Phosphorus via Ionization Journal Article PHYSICAL REVIEW LETTERS, 128 (17), 2022, ISSN: 0031-9007. @article{ISI:000804572300005, title = {Electronic Self-Passivation of Single Vacancy in Black Phosphorus via Ionization}, author = {Hanyan Fang and Aurelio Gallardo and Dikshant Dulal and Zhizhan Qiu and Jie Su and Mykola Telychko and Harshitra Mahalingam and Pin Lyu and Yixuan Han and Yi Zheng and Yongqing Cai and Aleksandr Rodin and Pavel Jelinek and Jiong Lu}, doi = {10.1103/PhysRevLett.128.176801}, times_cited = {9}, issn = {0031-9007}, year = {2022}, date = {2022-04-26}, journal = {PHYSICAL REVIEW LETTERS}, volume = {128}, number = {17}, publisher = {AMER PHYSICAL SOC}, address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA}, abstract = {We report that monoelemental black phosphorus presents a new electronic self-passivation scheme of single vacancy (SV). By means of low-temperature scanning tunneling microscopy and noncontact atomic force microscopy, we demonstrate that the local reconstruction and ionization of SV into negatively charged SV??? leads to the passivation of dangling bonds and, thus, the quenching of in-gap states, which can be achieved by mild thermal annealing or STM tip manipulation. SV exhibits a strong and symmetric Friedel oscillation (FO) pattern, while SV??? shows an asymmetric FO pattern with local perturbation amplitude reduced by one order of magnitude and a faster decay rate. The enhanced passivation by forming SV??? can be attributed to its weak dipolelike perturbation, consistent with density-functional theory numerical calculations. Therefore, self-passivated SV??? is electrically benign and acts as a much weaker scattering center, which may hold the key to further enhance the charge mobility of black phosphorus and its analogs.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report that monoelemental black phosphorus presents a new electronic self-passivation scheme of single vacancy (SV). By means of low-temperature scanning tunneling microscopy and noncontact atomic force microscopy, we demonstrate that the local reconstruction and ionization of SV into negatively charged SV??? leads to the passivation of dangling bonds and, thus, the quenching of in-gap states, which can be achieved by mild thermal annealing or STM tip manipulation. SV exhibits a strong and symmetric Friedel oscillation (FO) pattern, while SV??? shows an asymmetric FO pattern with local perturbation amplitude reduced by one order of magnitude and a faster decay rate. The enhanced passivation by forming SV??? can be attributed to its weak dipolelike perturbation, consistent with density-functional theory numerical calculations. Therefore, self-passivated SV??? is electrically benign and acts as a much weaker scattering center, which may hold the key to further enhance the charge mobility of black phosphorus and its analogs. |
Telychko, Mykola; Edalatmanesh, Shayan; Leng, Kai; Abdelwahab, Ibrahim; Guo, Na; Zhang, Chun; Mendieta-Moreno, Jesus; Nachtigall, Matyas; Li, Jing; Loh, Kian Ping; Jelinek, Pavel; Lu, Jiong Sub-angstrom noninvasive imaging of atomic arrangement in 2D hybrid perovskites Journal Article SCIENCE ADVANCES, 8 (17), 2022, ISSN: 2375-2548. @article{ISI:000790076700005, title = {Sub-angstrom noninvasive imaging of atomic arrangement in 2D hybrid perovskites}, author = {Mykola Telychko and Shayan Edalatmanesh and Kai Leng and Ibrahim Abdelwahab and Na Guo and Chun Zhang and Jesus Mendieta-Moreno and Matyas Nachtigall and Jing Li and Kian Ping Loh and Pavel Jelinek and Jiong Lu}, doi = {10.1126/sciadv.abj0395}, times_cited = {9}, issn = {2375-2548}, year = {2022}, date = {2022-04-01}, journal = {SCIENCE ADVANCES}, volume = {8}, number = {17}, publisher = {AMER ASSOC ADVANCEMENT SCIENCE}, address = {1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA}, abstract = {Noninvasive imaging of the atomic arrangement in two-dimensional (2D) Ruddlesden-Popper hybrid perovskites (RPPs) is challenging because of the insulating nature and softness of the organic layers. Here, we demonstrate a sub-angstrom resolution imaging of both soft organic layers and inorganic framework in a prototypical 2D lead-halide RPP crystal via combined tip-functionalized scanning tunneling microscopy (STM) and noncontact atomic force microscopy (ncAFM) corroborated by theoretical simulations. STM measurements unveil the atomic reconstruction of the inorganic lead-halide lattice and overall twin-domain composition of the RPP crystal, while ncAFM measurements with a CO-tip enable nonperturbative visualization of the cooperative reordering of surface organic cations driven by their hydrogen bonding interactions with the inorganic lattice. Moreover, such a joint technique also allows for the atomic-scale imaging of the electrostatic potential variation across the twin-domain walls, revealing alternating quasi-1D electron and hole channels at neighboring twin boundaries, which may influence in-plane exciton transport and dissociation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Noninvasive imaging of the atomic arrangement in two-dimensional (2D) Ruddlesden-Popper hybrid perovskites (RPPs) is challenging because of the insulating nature and softness of the organic layers. Here, we demonstrate a sub-angstrom resolution imaging of both soft organic layers and inorganic framework in a prototypical 2D lead-halide RPP crystal via combined tip-functionalized scanning tunneling microscopy (STM) and noncontact atomic force microscopy (ncAFM) corroborated by theoretical simulations. STM measurements unveil the atomic reconstruction of the inorganic lead-halide lattice and overall twin-domain composition of the RPP crystal, while ncAFM measurements with a CO-tip enable nonperturbative visualization of the cooperative reordering of surface organic cations driven by their hydrogen bonding interactions with the inorganic lattice. Moreover, such a joint technique also allows for the atomic-scale imaging of the electrostatic potential variation across the twin-domain walls, revealing alternating quasi-1D electron and hole channels at neighboring twin boundaries, which may influence in-plane exciton transport and dissociation. |
Zhang, Taiming; Grzeszczyk, Magdalena; Li, Jing; Yu, Wei; Xu, Haomin; He, Peng; Yang, Liming; Qiu, Zhizhan; Lin, HuiHui; Yang, Huimin; Zeng, Jian; Sun, Tao; Li, Zejun; Wu, Jishan; Lin, Ming; Loh, Kian Ping; Su, Chenliang; Novoselov, Kostya S; Carvalho, Alexandra; Koperski, Maciej; Lu, Jiong Degradation Chemistry and Kinetic Stabilization of Magnetic CrI3 Journal Article 20 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 144 (12), pp. 5295-5303, 2022, ISSN: 0002-7863. @article{ISI:000799109400015, title = {Degradation Chemistry and Kinetic Stabilization of Magnetic CrI_{3}}, author = {Taiming Zhang and Magdalena Grzeszczyk and Jing Li and Wei Yu and Haomin Xu and Peng He and Liming Yang and Zhizhan Qiu and HuiHui Lin and Huimin Yang and Jian Zeng and Tao Sun and Zejun Li and Jishan Wu and Ming Lin and Kian Ping Loh and Chenliang Su and Kostya S Novoselov and Alexandra Carvalho and Maciej Koperski and Jiong Lu}, doi = {10.1021/jacs.1c08906}, times_cited = {20}, issn = {0002-7863}, year = {2022}, date = {2022-03-30}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {144}, number = {12}, pages = {5295-5303}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {The discovery of the intrinsic magnetic order in single-layer chromium trihalides (CrX3, X = I, Br, and Cl) has drawn intensive interest due to their potential application in spintronic devices. However, the notorious environmental instability of this class of materials under ambient conditions renders their device fabrication and practical application extremely challenging. Her; we performed a systematic investigation of the degradation chemistry of chromium iodide (CrI3), the most studied among CrX3 families, via a joint spectroscopic and microscopic analysis of the structural and composition evolution of bulk and exfoliated nanoflakes in different environments. Unlike other air-sensitive 2D materials, CrI3 undergoes a pseudo-first-order hydrolysis in the presence of pure water toward the formation of amorphous Cr(OH)(3) and hydrogen iodide (HI) with a rate constant of k(1) = 0.63 day(-1) without light. In contrast, a faster pseudo-first-order surface oxidation of CrI3 occurs in a pure O-2 environment, generating CrO3 and I-2 with a large rate constant of k(Cr) = 4.2 day(-1). Both hydrolysis and surface oxidation of CrI3 can be accelerated via light irradiation, resulting in its ultrafast degradation in air. The new chemical insights obtained allow for the design of an effective stabilization strategy for CrI3 with preserved optical and magnetic properties. The use of organic acid solvents (e.g., formic acid) as reversible capping agents ensures that CrI3 nanoflakes remain stable beyond 1 month due to the effective suppression of both hydrolysis and oxidation of CrI3.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The discovery of the intrinsic magnetic order in single-layer chromium trihalides (CrX3, X = I, Br, and Cl) has drawn intensive interest due to their potential application in spintronic devices. However, the notorious environmental instability of this class of materials under ambient conditions renders their device fabrication and practical application extremely challenging. Her; we performed a systematic investigation of the degradation chemistry of chromium iodide (CrI3), the most studied among CrX3 families, via a joint spectroscopic and microscopic analysis of the structural and composition evolution of bulk and exfoliated nanoflakes in different environments. Unlike other air-sensitive 2D materials, CrI3 undergoes a pseudo-first-order hydrolysis in the presence of pure water toward the formation of amorphous Cr(OH)(3) and hydrogen iodide (HI) with a rate constant of k(1) = 0.63 day(-1) without light. In contrast, a faster pseudo-first-order surface oxidation of CrI3 occurs in a pure O-2 environment, generating CrO3 and I-2 with a large rate constant of k(Cr) = 4.2 day(-1). Both hydrolysis and surface oxidation of CrI3 can be accelerated via light irradiation, resulting in its ultrafast degradation in air. The new chemical insights obtained allow for the design of an effective stabilization strategy for CrI3 with preserved optical and magnetic properties. The use of organic acid solvents (e.g., formic acid) as reversible capping agents ensures that CrI3 nanoflakes remain stable beyond 1 month due to the effective suppression of both hydrolysis and oxidation of CrI3. |
2021 |
Hai, Xiao; Xi, Shibo; Mitchell, Sharon; Harrath, Karim; Xu, Haomin; Akl, Dario Faust; Kong, Debin; Li, Jing; Li, Zejun; Sun, Tao; Yang, Huimin; Cui, Yige; Su, Chenliang; Zhao, Xiaoxu; Li, Jun; Perez-Ramirez, Javier; Lu, Jiong Scalable two-step annealing method for preparing ultra-high-density single-atom catalyst libraries Journal Article 375 NATURE NANOTECHNOLOGY, 17 (2), pp. 174-+, 2021, ISSN: 1748-3387. @article{ISI:000722472000001, title = {Scalable two-step annealing method for preparing ultra-high-density single-atom catalyst libraries}, author = {Xiao Hai and Shibo Xi and Sharon Mitchell and Karim Harrath and Haomin Xu and Dario Faust Akl and Debin Kong and Jing Li and Zejun Li and Tao Sun and Huimin Yang and Yige Cui and Chenliang Su and Xiaoxu Zhao and Jun Li and Javier Perez-Ramirez and Jiong Lu}, doi = {10.1038/s41565-021-01022-y}, times_cited = {375}, issn = {1748-3387}, year = {2021}, date = {2021-11-25}, journal = {NATURE NANOTECHNOLOGY}, volume = {17}, number = {2}, pages = {174-+}, publisher = {NATURE PORTFOLIO}, address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY}, abstract = {A general versatile approach combining wet-chemistry impregnation and two-step annealing is devised for the scalable synthesis of a library of ultra-high-density single-atom catalysts with drastically enhanced reactivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A general versatile approach combining wet-chemistry impregnation and two-step annealing is devised for the scalable synthesis of a library of ultra-high-density single-atom catalysts with drastically enhanced reactivity. |
Peng, Xinnan; Mahalingam, Harshitra; Dong, Shaoqiang; Mutombo, Pingo; Su, Jie; Telychko, Mykola; Song, Shaotang; Lyu, Pin; Ng, Pei Wen; Wu, Jishan; Jelinek, Pavel; Chi, Chunyan; Rodin, Aleksandr; Lu, Jiong Visualizing designer quantum states in stable macrocycle quantum corrals Journal Article 13 NATURE COMMUNICATIONS, 12 (1), 2021. @article{ISI:000705238300007, title = {Visualizing designer quantum states in stable macrocycle quantum corrals}, author = {Xinnan Peng and Harshitra Mahalingam and Shaoqiang Dong and Pingo Mutombo and Jie Su and Mykola Telychko and Shaotang Song and Pin Lyu and Pei Wen Ng and Jishan Wu and Pavel Jelinek and Chunyan Chi and Aleksandr Rodin and Jiong Lu}, doi = {10.1038/s41467-021-26198-8}, times_cited = {13}, year = {2021}, date = {2021-10-08}, journal = {NATURE COMMUNICATIONS}, volume = {12}, number = {1}, publisher = {NATURE PORTFOLIO}, address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY}, abstract = {Creating atomically-precise quantum architectures with high digital fidelity and desired quantum states is an important goal for quantum technology applications. Here the authors devise an on-surface synthetic protocol to construct atomically-precise covalently linked organic quantum corrals with the formation of a series of new quantum resonance states.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Creating atomically-precise quantum architectures with high digital fidelity and desired quantum states is an important goal for quantum technology applications. Here the authors devise an on-surface synthetic protocol to construct atomically-precise covalently linked organic quantum corrals with the formation of a series of new quantum resonance states. |
Telychko, Mykola; Wang, Lulu; Hsu, Chia-Hsiu; Li, Guangwu; Peng, Xinnan; Song, Shaotang; Su, Jie; Chuang, Feng-Chuan; Wu, Jishan; Wong, Ming Wah; Lu, Jiong Tailoring long-range superlattice chirality in molecular self-assemblies via weak fluorine-mediated interactions Journal Article PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 23 (38), pp. 21489-21495, 2021, ISSN: 1463-9076. @article{ISI:000698166800001, title = {Tailoring long-range superlattice chirality in molecular self-assemblies \textit{via} weak fluorine-mediated interactions}, author = {Mykola Telychko and Lulu Wang and Chia-Hsiu Hsu and Guangwu Li and Xinnan Peng and Shaotang Song and Jie Su and Feng-Chuan Chuang and Jishan Wu and Ming Wah Wong and Jiong Lu}, doi = {10.1039/d1cp02996g}, times_cited = {3}, issn = {1463-9076}, year = {2021}, date = {2021-09-07}, journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, volume = {23}, number = {38}, pages = {21489-21495}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {Controllable fabrication of enantiospecific molecular superlattices is a matter of imminent scientific and technological interest. Herein, we demonstrate that long-range superlattice chirality in molecular self-assemblies can be tailored by tuning the interplay of weak intermolecular non-covalent interactions between hexaphenylbenzene-based enantiomers. By means of high-resolution scanning tunneling microscopy measurements, we demonstrate that the functionalization of a hexaphenylbenzene-based molecule with fluorine (F) atoms leads to the formation of molecular self-assemblies with distinct long-range chiral recognition patterns. We employed density functional theory calculations to quantify F-mediated lone pair FMIDLINE HORIZONTAL ELLIPSIS pi, C-HMIDLINE HORIZONTAL ELLIPSISF, and FMIDLINE HORIZONTAL ELLIPSISF interactions attributed to the distinct enantiospecific molecular self-organizations. Our findings underpin a viable route to fabricate long-range chiral recognition patterns in supramolecular assemblies by engineering the weak non-covalent intermolecular interactions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Controllable fabrication of enantiospecific molecular superlattices is a matter of imminent scientific and technological interest. Herein, we demonstrate that long-range superlattice chirality in molecular self-assemblies can be tailored by tuning the interplay of weak intermolecular non-covalent interactions between hexaphenylbenzene-based enantiomers. By means of high-resolution scanning tunneling microscopy measurements, we demonstrate that the functionalization of a hexaphenylbenzene-based molecule with fluorine (F) atoms leads to the formation of molecular self-assemblies with distinct long-range chiral recognition patterns. We employed density functional theory calculations to quantify F-mediated lone pair FMIDLINE HORIZONTAL ELLIPSIS pi, C-HMIDLINE HORIZONTAL ELLIPSISF, and FMIDLINE HORIZONTAL ELLIPSISF interactions attributed to the distinct enantiospecific molecular self-organizations. Our findings underpin a viable route to fabricate long-range chiral recognition patterns in supramolecular assemblies by engineering the weak non-covalent intermolecular interactions. |
Song, Shaotang; Wang, Lulu; Su, Jie; Xu, Zhen; Hsu, Chia-Hsiu; Hua, Chenqiang; Lyu, Pin; Li, Jing; Peng, Xinnan; Kojima, Takahiro; Nobusue, Shunpei; Telychko, Mykola; Zheng, Yi; Chuang, Feng-Chuan; Sakaguchi, Hiroshi; Wong, Ming Wah; Lu, Jiong Manifold dynamic non-covalent interactions for steering molecular assembly and cyclization Journal Article 14 CHEMICAL SCIENCE, 12 (35), pp. 11659-11667, 2021, ISSN: 2041-6520. @article{ISI:000688187700001, title = {Manifold dynamic non-covalent interactions for steering molecular assembly and cyclization}, author = {Shaotang Song and Lulu Wang and Jie Su and Zhen Xu and Chia-Hsiu Hsu and Chenqiang Hua and Pin Lyu and Jing Li and Xinnan Peng and Takahiro Kojima and Shunpei Nobusue and Mykola Telychko and Yi Zheng and Feng-Chuan Chuang and Hiroshi Sakaguchi and Ming Wah Wong and Jiong Lu}, doi = {10.1039/d1sc03733a}, times_cited = {14}, issn = {2041-6520}, year = {2021}, date = {2021-08-05}, journal = {CHEMICAL SCIENCE}, volume = {12}, number = {35}, pages = {11659-11667}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {Deciphering rich non-covalent interactions that govern many chemical and biological processes is crucial for the design of drugs and controlling molecular assemblies and their chemical transformations. However, real-space characterization of these weak interactions in complex molecular architectures at the single bond level has been a longstanding challenge. Here, we employed bond-resolved scanning probe microscopy combined with an exhaustive structural search algorithm and quantum chemistry calculations to elucidate multiple non-covalent interactions that control the cohesive molecular clustering of well-designed precursor molecules and their chemical reactions. The presence of two flexible bromo-triphenyl moieties in the precursor leads to the assembly of distinct non-planar dimer and trimer clusters by manifold non-covalent interactions, including hydrogen bonding, halogen bonding, C-HMIDLINE HORIZONTAL ELLIPSIS pi and lone pairMIDLINE HORIZONTAL ELLIPSIS pi interactions. The dynamic nature of weak interactions allows for transforming dimers into energetically more favourable trimers as molecular density increases. The formation of trimers also facilitates thermally-triggered intermolecular Ullmann coupling reactions, while the disassembly of dimers favours intramolecular cyclization, as evidenced by bond-resolved imaging of metalorganic intermediates and final products. The richness of manifold non-covalent interactions offers unprecedented opportunities for controlling the assembly of complex molecular architectures and steering on-surface synthesis of quantum nanostructures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Deciphering rich non-covalent interactions that govern many chemical and biological processes is crucial for the design of drugs and controlling molecular assemblies and their chemical transformations. However, real-space characterization of these weak interactions in complex molecular architectures at the single bond level has been a longstanding challenge. Here, we employed bond-resolved scanning probe microscopy combined with an exhaustive structural search algorithm and quantum chemistry calculations to elucidate multiple non-covalent interactions that control the cohesive molecular clustering of well-designed precursor molecules and their chemical reactions. The presence of two flexible bromo-triphenyl moieties in the precursor leads to the assembly of distinct non-planar dimer and trimer clusters by manifold non-covalent interactions, including hydrogen bonding, halogen bonding, C-HMIDLINE HORIZONTAL ELLIPSIS pi and lone pairMIDLINE HORIZONTAL ELLIPSIS pi interactions. The dynamic nature of weak interactions allows for transforming dimers into energetically more favourable trimers as molecular density increases. The formation of trimers also facilitates thermally-triggered intermolecular Ullmann coupling reactions, while the disassembly of dimers favours intramolecular cyclization, as evidenced by bond-resolved imaging of metalorganic intermediates and final products. The richness of manifold non-covalent interactions offers unprecedented opportunities for controlling the assembly of complex molecular architectures and steering on-surface synthesis of quantum nanostructures. |