Haomin Xu
CA2DM Publications:
2023 |
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 = {0}, issn = {2095-5138}, year = {2023}, date = {2023-01-14}, 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 |
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 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 = {0}, 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 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 = {0}, 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. |
Chen, Cheng; Ou, Wei; Yam, Kah-Meng; Xi, Shibo; Zhao, Xiaoxu; Chen, Si; Li, Jing; Lyu, Pin; Ma, Lu; Du, Yonghua; Yu, Wei; Fang, Hanyan; Yao, Chuanhao; Hai, Xiao; Xu, Haomin; Koh, Ming Joo; Pennycook, Stephen J; Lu, Junling; Lin, Ming; Su, Chenliang; Zhang, Chun; Lu, Jiong Zero-Valent Palladium Single-Atoms Catalysts Confined in Black Phosphorus for Efficient Semi-Hydrogenation Journal Article ADVANCED MATERIALS, 33 (35), 2021, ISSN: 0935-9648. @article{ISI:000676091000001, title = {Zero-Valent Palladium Single-Atoms Catalysts Confined in Black Phosphorus for Efficient Semi-Hydrogenation}, author = {Cheng Chen and Wei Ou and Kah-Meng Yam and Shibo Xi and Xiaoxu Zhao and Si Chen and Jing Li and Pin Lyu and Lu Ma and Yonghua Du and Wei Yu and Hanyan Fang and Chuanhao Yao and Xiao Hai and Haomin Xu and Ming Joo Koh and Stephen J Pennycook and Junling Lu and Ming Lin and Chenliang Su and Chun Zhang and Jiong Lu}, doi = {10.1002/adma.202008471}, times_cited = {0}, issn = {0935-9648}, year = {2021}, date = {2021-07-23}, journal = {ADVANCED MATERIALS}, volume = {33}, number = {35}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Single-atom catalysts (SACs) represent a new frontier in heterogeneous catalysis due to their remarkable catalytic properties and maximized atomic utilization. However, single atoms often bond to the support with polarized electron density and thus exhibit a high valence state, limiting their catalytic scopes in many chemical transformations. Here, it is demonstrated that 2D black phosphorus (BP) acts as giant phosphorus (P) ligand to confine a high density of single atoms (e.g., Pd-1, Pt-1) via atomic layer deposition. Unlike other 2D materials, BP with relatively low electronegativity and buckled structure favors the strong confinement of robust zero-valent palladium SACs in the vacancy site. Metallic Pd-1/BP SAC shows a highly selective semi-hydrogenation of phenylacetylene toward styrene, distinct from metallic Pd nanoparticles that facilitate the formation of fully hydrogenated products. Density functional theory calculations reveal that Pd atom forms covalent-like bonding with adjacent P atoms, wherein H atoms tend to adsorb, aiding the dissociative adsorption of H-2. Zero-valent Pd in the confined space favors a larger energy gain for the synthesis of partially hydrogenated product over the fully hydrogenated one. This work provides a new route toward the synthesis of zero-valent SACs on BP for organic transformations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Single-atom catalysts (SACs) represent a new frontier in heterogeneous catalysis due to their remarkable catalytic properties and maximized atomic utilization. However, single atoms often bond to the support with polarized electron density and thus exhibit a high valence state, limiting their catalytic scopes in many chemical transformations. Here, it is demonstrated that 2D black phosphorus (BP) acts as giant phosphorus (P) ligand to confine a high density of single atoms (e.g., Pd-1, Pt-1) via atomic layer deposition. Unlike other 2D materials, BP with relatively low electronegativity and buckled structure favors the strong confinement of robust zero-valent palladium SACs in the vacancy site. Metallic Pd-1/BP SAC shows a highly selective semi-hydrogenation of phenylacetylene toward styrene, distinct from metallic Pd nanoparticles that facilitate the formation of fully hydrogenated products. Density functional theory calculations reveal that Pd atom forms covalent-like bonding with adjacent P atoms, wherein H atoms tend to adsorb, aiding the dissociative adsorption of H-2. Zero-valent Pd in the confined space favors a larger energy gain for the synthesis of partially hydrogenated product over the fully hydrogenated one. This work provides a new route toward the synthesis of zero-valent SACs on BP for organic transformations. |
Li, Zejun; Wang, Zeyu; Xi, Shibo; Zhao, Xiaoxu; Sun, Tao; Li, Jing; Yu, Wei; Xu, Haomin; Herng, Tun Seng; Hai, Xiao; Lyu, Pin; Zhao, Meng; Pennycook, Stephen J; Ding, Jun; Xiao, Hai; Lu, Jiong Tuning the Spin Density of Cobalt Single-Atom Catalysts for Efficient Oxygen Evolution Journal Article ACS NANO, 15 (4), pp. 7105-7113, 2021, ISSN: 1936-0851. @article{ISI:000645436800099, title = {Tuning the Spin Density of Cobalt Single-Atom Catalysts for Efficient Oxygen Evolution}, author = {Zejun Li and Zeyu Wang and Shibo Xi and Xiaoxu Zhao and Tao Sun and Jing Li and Wei Yu and Haomin Xu and Tun Seng Herng and Xiao Hai and Pin Lyu and Meng Zhao and Stephen J Pennycook and Jun Ding and Hai Xiao and Jiong Lu}, doi = {10.1021/acsnano.1c00251}, times_cited = {0}, issn = {1936-0851}, year = {2021}, date = {2021-03-31}, journal = {ACS NANO}, volume = {15}, number = {4}, pages = {7105-7113}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {Single-atom catalysts (SACs) with magnetic elements as the active center have been widely exploited for efficient electrochemical conversions. Understanding the catalytic role of spin, and thus modulating the spin density of a single-atom center, is of profound fundamental interest and technological impact. Here, we synthesized ferromagnetic single Co atom catalysts on TaS2 monolayers (Co-1/TaS2) as a model system to explore the spin-activity correlation for the oxygen evolution reaction (OER). A single Co atom adsorbed at the hollow site (Co-HS) with spin-polarized electronic states serves as the active site for OER, whose spin density can be regulated by its neighboring single Co site via tuning the Co loading. Both experimental and theoretical results reveal the spin density-dependent OER activity that an optimal spin density of Co-HS can be achieved with a neighboring hetero-single Co-Ta site (substitution of Ta by Co) for a superior OER performance, in contrast to a homo-single Co-HS site, which creates an excessive spin density over vicinal Co-HS. An optimized spin density of Co-HS results in an optimal binding energy of oxygen species for the OER. Establishing the spin-activity correlation in SACs may create a descriptor for designing efficient magnetic SACs for renewable energy conversions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Single-atom catalysts (SACs) with magnetic elements as the active center have been widely exploited for efficient electrochemical conversions. Understanding the catalytic role of spin, and thus modulating the spin density of a single-atom center, is of profound fundamental interest and technological impact. Here, we synthesized ferromagnetic single Co atom catalysts on TaS2 monolayers (Co-1/TaS2) as a model system to explore the spin-activity correlation for the oxygen evolution reaction (OER). A single Co atom adsorbed at the hollow site (Co-HS) with spin-polarized electronic states serves as the active site for OER, whose spin density can be regulated by its neighboring single Co site via tuning the Co loading. Both experimental and theoretical results reveal the spin density-dependent OER activity that an optimal spin density of Co-HS can be achieved with a neighboring hetero-single Co-Ta site (substitution of Ta by Co) for a superior OER performance, in contrast to a homo-single Co-HS site, which creates an excessive spin density over vicinal Co-HS. An optimized spin density of Co-HS results in an optimal binding energy of oxygen species for the OER. Establishing the spin-activity correlation in SACs may create a descriptor for designing efficient magnetic SACs for renewable energy conversions. |
Ma, Yaping; Shao, Xiji; Li, Jing; Dong, Bowei; Hu, Zhenliang; Zhou, Qiulan; Xu, Haomin; Zhao, Xiaoxu; Fang, Hanyan; Li, Xinzhe; Li, Zejun; Wu, Jing; Zhao, Meng; Pennycook, Stephen John; Sow, Chorng Haur; Lee, Chengkuo; Zhong, Yu Lin; Lu, Junpeng; Ding, Mengning; Wang, Kedong; Li, Ying; Lu, Jiong Electrochemically Exfoliated Platinum Dichalcogenide Atomic Layers for High-Performance Air-Stable Infrared Photodetectors Journal Article ACS APPLIED MATERIALS & INTERFACES, 13 (7), pp. 8518-8527, 2021, ISSN: 1944-8244. @article{ISI:000623228500064, title = {Electrochemically Exfoliated Platinum Dichalcogenide Atomic Layers for High-Performance Air-Stable Infrared Photodetectors}, author = {Yaping Ma and Xiji Shao and Jing Li and Bowei Dong and Zhenliang Hu and Qiulan Zhou and Haomin Xu and Xiaoxu Zhao and Hanyan Fang and Xinzhe Li and Zejun Li and Jing Wu and Meng Zhao and Stephen John Pennycook and Chorng Haur Sow and Chengkuo Lee and Yu Lin Zhong and Junpeng Lu and Mengning Ding and Kedong Wang and Ying Li and Jiong Lu}, doi = {10.1021/acsami.0c20535}, times_cited = {0}, issn = {1944-8244}, year = {2021}, date = {2021-02-11}, journal = {ACS APPLIED MATERIALS & INTERFACES}, volume = {13}, number = {7}, pages = {8518-8527}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {Platinum dichalcogenide (PtX2), an emergent group-10 transition metal dichalcogenide (TMD) has shown great potential in infrared photonic and optoelectronic applications due to its layer-dependent electronic structure with potentially suitable bandgap. However, a scalable synthesis of PtSe2 and PtTe2 atomic layers with controlled thickness still represents a major challenge in this field because of the strong interlayer interactions. Herein, we develop a facile cathodic exfoliation approach for the synthesis of solution-processable high-quality PtSe2 and PtTe2 atomic layers for high-performance infrared (IR) photodetection. As-exfoliated PtSe2 and PtTe2 bilayer exhibit an excellent photoresponsivity of 72 and 1620 mA W-1 at zero gate voltage under a 1540 nm laser illumination, respectively, approximately several orders of magnitude higher than that of the majority of IR photodetectors based on graphene, TMDs, and black phosphorus. In addition, our PtSe2 and PtTe2 bilayer device also shows a decent specific detectivity of beyond 10(9) Jones with remarkable air-stability (>several months), outperforming the mechanically exfoliated counterparts under the laser illumination with a similar wavelength. Moreover, a high yield of PtSe2 and PtTe2 atomic layers dispersed in solution also allows for a facile fabrication of air-stable wafer-scale IR photodetector. This work demonstrates a new route for the synthesis of solution-processable layered materials with the narrow bandgap for the infrared optoelectronic applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Platinum dichalcogenide (PtX2), an emergent group-10 transition metal dichalcogenide (TMD) has shown great potential in infrared photonic and optoelectronic applications due to its layer-dependent electronic structure with potentially suitable bandgap. However, a scalable synthesis of PtSe2 and PtTe2 atomic layers with controlled thickness still represents a major challenge in this field because of the strong interlayer interactions. Herein, we develop a facile cathodic exfoliation approach for the synthesis of solution-processable high-quality PtSe2 and PtTe2 atomic layers for high-performance infrared (IR) photodetection. As-exfoliated PtSe2 and PtTe2 bilayer exhibit an excellent photoresponsivity of 72 and 1620 mA W-1 at zero gate voltage under a 1540 nm laser illumination, respectively, approximately several orders of magnitude higher than that of the majority of IR photodetectors based on graphene, TMDs, and black phosphorus. In addition, our PtSe2 and PtTe2 bilayer device also shows a decent specific detectivity of beyond 10(9) Jones with remarkable air-stability (>several months), outperforming the mechanically exfoliated counterparts under the laser illumination with a similar wavelength. Moreover, a high yield of PtSe2 and PtTe2 atomic layers dispersed in solution also allows for a facile fabrication of air-stable wafer-scale IR photodetector. This work demonstrates a new route for the synthesis of solution-processable layered materials with the narrow bandgap for the infrared optoelectronic applications. |
2020 |
Li, Jing; Song, Peng; Zhao, Jinpei; Vaklinova, Kristina; Zhao, Xiaoxu; Li, Zejun; Qiu, Zhizhan; Wang, Zihao; Lin, Li; Zhao, Meng; Herng, Tun Seng; Zuo, Yuxin; Jonhson, Win; Yu, Wei; Hai, Xiao; Lyu, Pin; Xu, Haomin; Yang, Huimin; Chen, Cheng; Pennycook, Stephen J; Ding, Jun; Teng, Jinghua; Neto, Castro A H; Novoselov, Kostya S; Lu, Jiong Printable two-dimensional superconducting monolayers Journal Article NATURE MATERIALS, 20 (2), pp. 181-+, 2020, ISSN: 1476-1122. @article{ISI:000584012400003, title = {Printable two-dimensional superconducting monolayers}, author = {Jing Li and Peng Song and Jinpei Zhao and Kristina Vaklinova and Xiaoxu Zhao and Zejun Li and Zhizhan Qiu and Zihao Wang and Li Lin and Meng Zhao and Tun Seng Herng and Yuxin Zuo and Win Jonhson and Wei Yu and Xiao Hai and Pin Lyu and Haomin Xu and Huimin Yang and Cheng Chen and Stephen J Pennycook and Jun Ding and Jinghua Teng and Castro A H Neto and Kostya S Novoselov and Jiong Lu}, doi = {10.1038/s41563-020-00831-1}, times_cited = {0}, issn = {1476-1122}, year = {2020}, date = {2020-10-26}, journal = {NATURE MATERIALS}, volume = {20}, number = {2}, pages = {181-+}, publisher = {NATURE RESEARCH}, address = {HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY}, abstract = {A mild electrochemical exfoliation method has been developed to obtain large-size two-dimensional superconductor monolayers with high crystallinity and production yield, which enables the easy fabrication of twisted van der Waals heterostructures and printed films.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A mild electrochemical exfoliation method has been developed to obtain large-size two-dimensional superconductor monolayers with high crystallinity and production yield, which enables the easy fabrication of twisted van der Waals heterostructures and printed films. |
Xu, Haomin; Xi, Shibo; Li, Jing; Liu, Shikai; Lyu, Pin; Yu, Wei; Sun, Tao; Qi, Dong-Chen; He, Qian; Xiao, Hai; Lin, Ming; Wu, Jishan; Zhang, Jia; Lu, Jiong Chemical design and synthesis of superior single-atom electrocatalystsvia in situpolymerization Journal Article JOURNAL OF MATERIALS CHEMISTRY A, 8 (34), pp. 17683-17690, 2020, ISSN: 2050-7488. @article{ISI:000566092600031, title = {Chemical design and synthesis of superior single-atom electrocatalysts\textit{via in situ}polymerization}, author = {Haomin Xu and Shibo Xi and Jing Li and Shikai Liu and Pin Lyu and Wei Yu and Tao Sun and Dong-Chen Qi and Qian He and Hai Xiao and Ming Lin and Jishan Wu and Jia Zhang and Jiong Lu}, doi = {10.1039/d0ta05130f}, times_cited = {0}, issn = {2050-7488}, year = {2020}, date = {2020-09-14}, journal = {JOURNAL OF MATERIALS CHEMISTRY A}, volume = {8}, number = {34}, pages = {17683-17690}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {Molecule-like electrocatalysts with FeN(4)motifs have been demonstrated to be excellent candidates for various renewable energy conversions. The ability to further tune the electronic properties of molecular FeN(4)motifs and integrate them onto conductive supports represents a key step towards the synthesis of highly robust and efficient single-atom catalysts (SACs) for practical applications. Here, we developed a new route for the synthesis of a well-defined single-atom FeN(4)electrocatalystvia in situpolymerization of four amino groups functionalized iron phthalocyanine (NH2-FePc) molecules on conductive carbon nanotubes. The intermolecular oxidative dimerization between the amino groups of NH2-FePc creates the desired electron-withdrawing pyrazine linker between FeN(4)motifs, which can significantly optimize their electrocatalytic performances. As a result, the FeN4-SAC exhibits both outstanding ORR activity (a half-wave potential of 0.88 Vvs.RHE) and excellent performance in Zn-oxygen batteries, outperforming the commercial Pt/C and pristine iron phthalocyanine (FePc) catalysts. Our theoretical calculations reveal that the presence of electron-withdrawing linkers shifts the occupied antibonding states towards lower energies and thus weakens the Fe-O bond, which is primarily responsible for the enhancement of ORR activity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Molecule-like electrocatalysts with FeN(4)motifs have been demonstrated to be excellent candidates for various renewable energy conversions. The ability to further tune the electronic properties of molecular FeN(4)motifs and integrate them onto conductive supports represents a key step towards the synthesis of highly robust and efficient single-atom catalysts (SACs) for practical applications. Here, we developed a new route for the synthesis of a well-defined single-atom FeN(4)electrocatalystvia in situpolymerization of four amino groups functionalized iron phthalocyanine (NH2-FePc) molecules on conductive carbon nanotubes. The intermolecular oxidative dimerization between the amino groups of NH2-FePc creates the desired electron-withdrawing pyrazine linker between FeN(4)motifs, which can significantly optimize their electrocatalytic performances. As a result, the FeN4-SAC exhibits both outstanding ORR activity (a half-wave potential of 0.88 Vvs.RHE) and excellent performance in Zn-oxygen batteries, outperforming the commercial Pt/C and pristine iron phthalocyanine (FePc) catalysts. Our theoretical calculations reveal that the presence of electron-withdrawing linkers shifts the occupied antibonding states towards lower energies and thus weakens the Fe-O bond, which is primarily responsible for the enhancement of ORR activity. |
Yao, Chuanhao; Guo, Na; Xi, Shibo; Xu, Cong-Qiao; Liu, Wei; Zhao, Xiaoxu; Li, Jing; Fang, Hanyan; Su, Jie; Chen, Zhongxin; Yan, Huan; Qiu, Zhizhan; Lyu, Pin; Chen, Cheng; Xu, Haomin; Peng, Xinnan; Li, Xinzhe; Liu, Bin; Su, Chenliang; Pennycook, Stephen J; Sun, Cheng-Jun; Li, Jun; Zhang, Chun; Du, Yonghua; Lu, Jiong Atomically-precise dopant-controlled single cluster catalysis for electrochemical nitrogen reduction Journal Article NATURE COMMUNICATIONS, 11 (1), 2020, ISSN: 2041-1723. @article{ISI:000569891500016, title = {Atomically-precise dopant-controlled single cluster catalysis for electrochemical nitrogen reduction}, author = {Chuanhao Yao and Na Guo and Shibo Xi and Cong-Qiao Xu and Wei Liu and Xiaoxu Zhao and Jing Li and Hanyan Fang and Jie Su and Zhongxin Chen and Huan Yan and Zhizhan Qiu and Pin Lyu and Cheng Chen and Haomin Xu and Xinnan Peng and Xinzhe Li and Bin Liu and Chenliang Su and Stephen J Pennycook and Cheng-Jun Sun and Jun Li and Chun Zhang and Yonghua Du and Jiong Lu}, doi = {10.1038/s41467-020-18080-w}, times_cited = {0}, issn = {2041-1723}, year = {2020}, date = {2020-09-01}, journal = {NATURE COMMUNICATIONS}, volume = {11}, number = {1}, publisher = {NATURE PUBLISHING GROUP}, address = {MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND}, abstract = {The ability to precisely engineer the doping of sub-nanometer bimetallic clusters offers exciting opportunities for tailoring their catalytic performance with atomic accuracy. However, the fabrication of singly dispersed bimetallic cluster catalysts with atomic-level control of dopants has been a long-standing challenge. Herein, we report a strategy for the controllable synthesis of a precisely doped single cluster catalyst consisting of partially ligand-enveloped Au4Pt2 clusters supported on defective graphene. This creates a bimetal single cluster catalyst (Au4Pt2/G) with exceptional activity for electrochemical nitrogen (N-2) reduction. Our mechanistic study reveals that each N-2 molecule is activated in the confined region between cluster and graphene. The heteroatom dopant plays an indispensable role in the activation of N-2 via an enhanced back donation of electrons to the N-2 LUMO. Moreover, besides the heteroatom Pt, the catalytic performance of single cluster catalyst can be further tuned by using Pd in place of Pt as the dopant. The fabrication of singly dispersed metal cluster catalysts with atomic-level control of dopants is a long-standing challenge. Here, the authors report a strategy for the synthesis of a precisely doped single cluster catalyst which shows exceptional activity for electrochemical dinitrogen reduction.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ability to precisely engineer the doping of sub-nanometer bimetallic clusters offers exciting opportunities for tailoring their catalytic performance with atomic accuracy. However, the fabrication of singly dispersed bimetallic cluster catalysts with atomic-level control of dopants has been a long-standing challenge. Herein, we report a strategy for the controllable synthesis of a precisely doped single cluster catalyst consisting of partially ligand-enveloped Au4Pt2 clusters supported on defective graphene. This creates a bimetal single cluster catalyst (Au4Pt2/G) with exceptional activity for electrochemical nitrogen (N-2) reduction. Our mechanistic study reveals that each N-2 molecule is activated in the confined region between cluster and graphene. The heteroatom dopant plays an indispensable role in the activation of N-2 via an enhanced back donation of electrons to the N-2 LUMO. Moreover, besides the heteroatom Pt, the catalytic performance of single cluster catalyst can be further tuned by using Pd in place of Pt as the dopant. The fabrication of singly dispersed metal cluster catalysts with atomic-level control of dopants is a long-standing challenge. Here, the authors report a strategy for the synthesis of a precisely doped single cluster catalyst which shows exceptional activity for electrochemical dinitrogen reduction. |
Li, Zejun; Zhang, Xiuying; Zhao, Xiaoxu; Li, Jing; Herng, Tun Seng; Xu, Haomin; Lin, Fanrong; Lyu, Pin; Peng, Xinnan; Yu, Wei; Hai, Xiao; Chen, Cheng; Yang, Huimin; Martin, Jens; Lu, Jing; Luo, Xin; Neto, Castro A H; Pennycook, Stephen J; Ding, Jun; Feng, Yuanping; Lu, Jiong Imprinting Ferromagnetism and Superconductivity in Single Atomic Layers of Molecular Superlattices Journal Article ADVANCED MATERIALS, 32 (25), 2020, ISSN: 0935-9648. @article{ISI:000533211300001, title = {Imprinting Ferromagnetism and Superconductivity in Single Atomic Layers of Molecular Superlattices}, author = {Zejun Li and Xiuying Zhang and Xiaoxu Zhao and Jing Li and Tun Seng Herng and Haomin Xu and Fanrong Lin and Pin Lyu and Xinnan Peng and Wei Yu and Xiao Hai and Cheng Chen and Huimin Yang and Jens Martin and Jing Lu and Xin Luo and Castro A H Neto and Stephen J Pennycook and Jun Ding and Yuanping Feng and Jiong Lu}, doi = {10.1002/adma.201907645}, times_cited = {0}, issn = {0935-9648}, year = {2020}, date = {2020-05-17}, journal = {ADVANCED MATERIALS}, volume = {32}, number = {25}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {Ferromagnetism and superconductivity are two antagonistic phenomena since ferromagnetic exchange fields tend to destroy singlet Cooper pairs. Reconciliation of these two competing phases has been achieved in vertically stacked heterostructures where these two orders are confined in different layers. However, controllable integration of these two phases in one atomic layer is a longstanding challenge. Here, an interlayer-space-confined chemical design (ICCD) is reported for the synthesis of dilute single-atom-doped TaS2 molecular superlattice, whereby ferromagnetism is observed in the superconducting TaS2 layers. The intercalation of 2H-TaS2 crystal with bulky organic ammonium molecule expands its van der Waals gap for single-atom doping via co-intercalated cobalt ions, resulting in the formation of quasi-monolayer Co-doped TaS2 superlattices. Isolated Co atoms are decorated in the basal plane of the TaS2 via substituting the Ta atom or anchoring at a hollow site, wherein the orbital-selected p-d hybridization between Co and neighboring Ta and S atoms induces local magnetic moments with strong ferromagnetic coupling. This ICCD approach can be applied to various metal ions, enabling the synthesis of a series of crystal-size TaS2 molecular superlattices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Ferromagnetism and superconductivity are two antagonistic phenomena since ferromagnetic exchange fields tend to destroy singlet Cooper pairs. Reconciliation of these two competing phases has been achieved in vertically stacked heterostructures where these two orders are confined in different layers. However, controllable integration of these two phases in one atomic layer is a longstanding challenge. Here, an interlayer-space-confined chemical design (ICCD) is reported for the synthesis of dilute single-atom-doped TaS2 molecular superlattice, whereby ferromagnetism is observed in the superconducting TaS2 layers. The intercalation of 2H-TaS2 crystal with bulky organic ammonium molecule expands its van der Waals gap for single-atom doping via co-intercalated cobalt ions, resulting in the formation of quasi-monolayer Co-doped TaS2 superlattices. Isolated Co atoms are decorated in the basal plane of the TaS2 via substituting the Ta atom or anchoring at a hollow site, wherein the orbital-selected p-d hybridization between Co and neighboring Ta and S atoms induces local magnetic moments with strong ferromagnetic coupling. This ICCD approach can be applied to various metal ions, enabling the synthesis of a series of crystal-size TaS2 molecular superlattices. |
Hai, Xiao; Zhao, Xiaoxu; Guo, Na; Yao, Chuanhao; Chen, Cheng; Liu, Wei; Du, Yonghua; Yan, Huan; Li, Jing; Chen, Zhongxin; Li, Xing; Li, Zejun; Xu, Haomin; Lyu, Pin; Zhang, Jia; Lin, Ming; Su, Chenliang; Pennycook, Stephen J; Zhang, Chun; Xi, Shibo; Lu, Jiong Engineering Local and Global Structures of Single Co Atoms for a Superior Oxygen Reduction Reaction Journal Article 16 ACS CATALYSIS, 10 (10), pp. 5862-5870, 2020, ISSN: 2155-5435. @article{ISI:000535291500050, title = {Engineering Local and Global Structures of Single Co Atoms for a Superior Oxygen Reduction Reaction}, author = {Xiao Hai and Xiaoxu Zhao and Na Guo and Chuanhao Yao and Cheng Chen and Wei Liu and Yonghua Du and Huan Yan and Jing Li and Zhongxin Chen and Xing Li and Zejun Li and Haomin Xu and Pin Lyu and Jia Zhang and Ming Lin and Chenliang Su and Stephen J Pennycook and Chun Zhang and Shibo Xi and Jiong Lu}, doi = {10.1021/acscatal.0c00936}, times_cited = {16}, issn = {2155-5435}, year = {2020}, date = {2020-05-15}, journal = {ACS CATALYSIS}, volume = {10}, number = {10}, pages = {5862-5870}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {The ability to tune both local and global environments of a single metal active center on a support is crucial for the development of highly robust and efficient single-atom electrocatalysts (SAECs) that can surmount both thermodynamic and kinetic constraints in electrocatalysis. Here, we designed a core-shell-structured SAEC (Co-1-SAC) with superior oxygen reduction reaction (ORR) performance. Co-1-SAC consists of a locally engineered single Co-N3C1 site on a N-doped microporous amorphous carbon support enveloped by a globally engineered highly conductive mesoporous graphitic carbon shell. Theoretical calculations reveal that Co-N3C1 exhibits near-Fermi electronic states distinct from those of Co-N2C2 and Co-N-4, which facilitate both the electronic hybridization with O-2 and the subsequent protonation of adsorbed O-2* toward the formation of OOH*. Engineering Co-N3C1-SAC into a micro/mesoporous structure dramatically enhances the mass transport and electron transfer, which further boosts the ORR and Zn-air battery performance (slightly outperforming Pt/C). Our findings open an avenue toward engineering of the local and global environment of SACs for a wide range of efficient electrochemical conversions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ability to tune both local and global environments of a single metal active center on a support is crucial for the development of highly robust and efficient single-atom electrocatalysts (SAECs) that can surmount both thermodynamic and kinetic constraints in electrocatalysis. Here, we designed a core-shell-structured SAEC (Co-1-SAC) with superior oxygen reduction reaction (ORR) performance. Co-1-SAC consists of a locally engineered single Co-N3C1 site on a N-doped microporous amorphous carbon support enveloped by a globally engineered highly conductive mesoporous graphitic carbon shell. Theoretical calculations reveal that Co-N3C1 exhibits near-Fermi electronic states distinct from those of Co-N2C2 and Co-N-4, which facilitate both the electronic hybridization with O-2 and the subsequent protonation of adsorbed O-2* toward the formation of OOH*. Engineering Co-N3C1-SAC into a micro/mesoporous structure dramatically enhances the mass transport and electron transfer, which further boosts the ORR and Zn-air battery performance (slightly outperforming Pt/C). Our findings open an avenue toward engineering of the local and global environment of SACs for a wide range of efficient electrochemical conversions. |
2019 |
Li, Jing; Liu, Wei; Chen, Cheng; Zhao, Xiaoxu; Qiu, Zhizhan; Xu, Haomin; Sheng, Feng; Hu, Qifeng; Zheng, Yi; Lin, Ming; Pennycook, Stephen J; Su, Chenliang; Lu, Jiong High yield electrochemical exfoliation synthesis of tin selenide quantum dots for high-performance lithium-ion batteries Journal Article JOURNAL OF MATERIALS CHEMISTRY A, 7 (41), pp. 23958-23963, 2019, ISSN: 2050-7488. @article{ISI:000508175800043, title = {High yield electrochemical exfoliation synthesis of tin selenide quantum dots for high-performance lithium-ion batteries}, author = {Jing Li and Wei Liu and Cheng Chen and Xiaoxu Zhao and Zhizhan Qiu and Haomin Xu and Feng Sheng and Qifeng Hu and Yi Zheng and Ming Lin and Stephen J Pennycook and Chenliang Su and Jiong Lu}, doi = {10.1039/c9ta04643g}, times_cited = {1}, issn = {2050-7488}, year = {2019}, date = {2019-11-07}, journal = {JOURNAL OF MATERIALS CHEMISTRY A}, volume = {7}, number = {41}, pages = {23958-23963}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {Tin selenide (SnSe) nanostructures hold great promise as an anode material in lithium-ion batteries (LIBs) due to their high storage capacity, rapid lithiation kinetics and long-term cycling stability. However, a scalable synthesis of SnSe nanostructures with a well-defined size remains a challenge in chemistry. Here, we report cathodic exfoliation of a bulk SnSe crystal for a high-yield (>90%) synthesis of sub-5 nm scale SnSe quantum dots (QDs). As-exfoliated SnSe QDs demonstrate a superior performance as the anode material for LIBs. Our results reveal that SnSe QDs not only accommodate the volume expansion/contraction during the reversible charging/discharging in LIBs but also increase the effective contact interface area between the nanostructured anode materials and electrolyte, leading to a high charging/discharging rate and superior cycling performance. Additionally, SnSe QD based LIBs exhibit a reversible capacity retention of 550 mA h g(-1) and high coulombic efficiency approaching 100% after 1500 charging/discharging cycles at a current density of 0.5 A g(-1).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Tin selenide (SnSe) nanostructures hold great promise as an anode material in lithium-ion batteries (LIBs) due to their high storage capacity, rapid lithiation kinetics and long-term cycling stability. However, a scalable synthesis of SnSe nanostructures with a well-defined size remains a challenge in chemistry. Here, we report cathodic exfoliation of a bulk SnSe crystal for a high-yield (>90%) synthesis of sub-5 nm scale SnSe quantum dots (QDs). As-exfoliated SnSe QDs demonstrate a superior performance as the anode material for LIBs. Our results reveal that SnSe QDs not only accommodate the volume expansion/contraction during the reversible charging/discharging in LIBs but also increase the effective contact interface area between the nanostructured anode materials and electrolyte, leading to a high charging/discharging rate and superior cycling performance. Additionally, SnSe QD based LIBs exhibit a reversible capacity retention of 550 mA h g(-1) and high coulombic efficiency approaching 100% after 1500 charging/discharging cycles at a current density of 0.5 A g(-1). |