@article{47dfcbd0779f4d7ab2fd88757263b257,
title = "Role of sulfur vacancies and undercoordinated Mo regions in MoS2 nanosheets toward the evolution of hydrogen",
abstract = "Low-dimensional materials have been examined as electrocatalysts for the hydrogen evolution reaction (HER). Among them, two-dimensional transition metal dichalcogenides (2D-TMDs) such as MoS2 have been identified as potential candidates. However, the performance of TMDs toward HER in both acidic and basic media remains inferior to that of noble metals such as Pt and its alloys. This calls for investigating the influence of controlled defect engineering of 2D TMDs on their performance toward hydrogen production. Here, we explored the HER activity from defective multilayered MoS2 over a large range of surface S vacancy concentrations up to 90%. Amorphous MoS2 and 2H MoS2 with ultrarich S vacancies demonstrated the highest HER performance in acid and basic electrolytes, respectively. We also report that the HER performance from multilayered MoS2 can be divided into two domains corresponding to {"}point defects{"} at low concentrations of surface S vacancies (Stage 1) and large regions of undercoordinated Mo atoms for high concentrations of surface S vacancies (Stage 2). The highest performance is obtained for Stage 2 in the presence of undercoordinated Mo atoms with a TOF of ∼2 s-1 at an overpotential of 160 mV in 0.1 M KOH which compares favorably to the best results in the literature. Overall, our work provides deeper insight on the HER mechanism from defected MoS2 and provides guidance for the development of defect-engineered TMD-based electrocatalysts.",
keywords = "H-annealing, Hydrogen evolution reaction, MoS, Sulfur vacancies, Undercoordinated Mo",
author = "Lei Li and Zhaodan Qin and Lucie Ries and Song Hong and Thierry Michel and Jieun Yang and Chrystelle Salameh and Mikhael Bechelany and Philippe Miele and Daniel Kaplan and Manish Chhowalla and Damien Voiry",
note = "Funding Information: D.V. acknowledges financial support from the US Army RDECOM Grant No W911NF-17-2-0033, the CNRS Cellule Energie exploratory Project: “R2D-CO2”. This project has also received partial funding from the European Research Council (ERC) under the European Union{\textquoteright}s Horizon 2020 research and innovation programme (grant agreement No 804320). L.L. acknowledges National Natural Science Foundation of China (21503092) and Zhejiang Provincial Natural Science Foundation of China (LY19B030005). L.R. acknowledges scholarship from the Graduate School “Ecole doctorale des Sciences Chimiques, ED 459”. We thank Corine Reibel and Dr. Erwan Oliviero for the electron paramagnetic resonance and electron microscopy, respectively. Funding Information: D.V. acknowledges financial support from the US Army RDECOM Grant No W911NF-17-2-0033, the CNRS Cellule Energie exploratory Project: {"}R2D-CO2{"}. This project has also received partial funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 804320). L.L. acknowledges National Natural Science Foundation of China (21503092) and Zhejiang Provincial Natural Science Foundation of China (LY19B030005). L.R. acknowledges scholarship from the Graduate School {"}Ecole doctorale des Sciences Chimiques, ED 459{"}. We thank Corine Reibel and Dr. Erwan Oliviero for the electron paramagnetic resonance and electron microscopy, respectively.",
year = "2019",
month = jun,
day = "25",
doi = "10.1021/acsnano.9b01583",
language = "English",
volume = "13",
pages = "6824--6834",
journal = "ACS Nano",
issn = "1936-0851",
publisher = "American Chemical Society",
number = "6",
}