Kedar Hippalgaonkar

@article{ISI:000555849400010,
title = {Large enhancement of thermoelectric performance in MoS_{2}/h-BN heterostructure due to vacancy-induced band hybridization (vol 117, pg 13929, 2020)},
author = {Jing Wu and Yanpeng Liu and Yi Liu and Yongqing Cai and Yunshan Zhao and Hong Kuan Ng and Kenji Watanabe and Takashi Taniguchi and Gang Zhang and Cheng-Wei Qiu and Dongzhi Chi and Castro A H Neto and John T L Thong and Kian Ping Loh and Kedar Hippalgaonkar},
doi = {10.1073/pnas.2012778117},
times_cited = {0},
issn = {0027-8424},
year = {2020},
date = {2020-07-28},
journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA},
volume = {117},
number = {30},
pages = {18127-18127},
publisher = {NATL ACAD SCIENCES},
address = {2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{ISI:000546763100018,
title = {Large enhancement of thermoelectric performance in MoS_{2}/\textit{h}-BN heterostructure due to vacancy -induced band hybridization},
author = {Jing Wu and Yanpeng Liu and Yi Liu and Yongqing Cai and Yunshan Zhao and Hong Kuan Ng and Kenji Watanabe and Takashi Taniguchi and Gang Zhang and Cheng-Wei Qiu and Dongzhi Chi and Castro A H Neto and John T L Thong and Kian Ping Loh and Kedar Hippalgaonkar},
doi = {10.1073/pnas.2007495117},
times_cited = {0},
issn = {0027-8424},
year = {2020},
date = {2020-06-23},
journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA},
volume = {117},
number = {25},
pages = {13929-13936},
publisher = {NATL ACAD SCIENCES},
address = {2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA},
abstract = {Local impurity states arising from atomic vacancies in two-dimensional (2D) nanosheets are predicted to have a profound effect on charge transport due to resonant scattering and can be used to manipulate thermoelectric properties. However, the effects of these impurities are often masked by external fluctuations and turbostratic inter- faces; therefore, it is challenging to probe the correlation between vacancy impurities and thermoelectric parameters experimentally. In this work, we demonstrate that n-type molybdenum disulfide (MoS2 ) supported on hexagonal boron nitride (h-BN) substrate re- veals a large anomalous positive Seebeck coefficient with strong band hybridization. The presence of vacancies on MoS2 with a large conduction subband splitting of 50.0 +/- 5.0 meV may contribute to Kondo insulator-like properties. Furthermore, by tuning the chem- ical potential, the thermoelectric power factor can be enhanced by up to two orders of magnitude to 50 mW m(-1) K-2 . Our work shows that defect engineering in 2D materials provides an effective strat- egy for controlling band structure and tuning thermoelectric transport.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{ISI:000463843900002,
title = {Effects Of Structural Phase Transition On Thermoelectric Performance in Lithium-Intercalated Molybdenum Disulfide (Li\textit{_{x}}MoS_{2})},
author = {Hong Kuan Ng and Anas Abutaha and Damien Voiry and Ivan Verzhbitskiy and Yongqing Cai and Gang Zhang and Yi Liu and Jing Wu and Manish Chhowalla and Goki Eda and Kedar Hippalgaonkar},
doi = {10.1021/acsami.8b22105},
times_cited = {0},
issn = {1944-8244},
year = {2019},
date = {2019-04-03},
journal = {ACS APPLIED MATERIALS & INTERFACES},
volume = {11},
number = {13},
pages = {12184-12189},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {Layered transition metal dichalcogenides (TMDCs) intercalated with alkali metals exhibit mixed metallic and semiconducting phases with variable fractions. Thermoelectric properties of such mixed-phase structure are of great interest because of the potential energy filtering effect, wherein interfacial energy barriers strongly scatter cold carriers rather than hot carriers, leading to enhanced Seebeck coefficient (S). Here, we study the thermoelectric properties of mixed-phase LixMoS2 as a function of its phase composition tuned by in situ thermally driven deintercalation. We find that the sign of Seebeck coefficient changes from positive to negative during initial reduction of the 1T/1T' phase fraction, indicating crossover from p- to n-type carrier conduction. These anomalous changes in Seebeck coefficient, which cannot be simply explained by the effect of deintercalation-induced reduction in carrier density, can be attributed to the hybrid electronic property of the mixed-phase LixMoS2. Our work shows that careful phase engineering is a promising route toward achieving thermoelectric performance in TMDCs.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}