TY - JOUR

T1 - Activating MoS 2 with Super-High Nitrogen-Doping Concentration as Efficient Catalyst for Hydrogen Evolution Reaction

AU - Yang, Qian

AU - Wang, Zegao

AU - Dong, Lichun

AU - Zhao, Wenbin

AU - Jin, Yan

AU - Fang, Liang

AU - Hu, Baoshan

AU - Dong, Mingdong

PY - 2019/5

Y1 - 2019/5

N2 - The development of nonprecious electrocatalysts with high hydrogen evolution reaction (HER) activity for water splitting is highly desirable but remains a significant challenge. Molybdenum disulfide (MoS 2 ) has been demonstrated as a good candidate; however, insufficient active sites along with poor conductivity significantly hinder the overall efficiency of MoS 2 . In this work, we present a method to activate commercial MoS 2 by high concentration nitrogen doping via a facile high-temperature treatment routine. The dominant N-doping mechanism is demonstrated to be an appropriate one-to-one substitution of sulfur atoms, which is confirmed by the approximate constancy between the atomic ratio of Mo/(S + N) and stoichiometric number of original MoS 2 . By controlling the activation time and temperature, the concentration of the doped nitrogen atoms can be tuned up to 41 atom %. The HER activity of the as-prepared materials was evaluated as electrode materials, showing that the catalytic activity is strongly correlated with the doped nitrogen concentration, and the catalytic current density of N-doped MoS 2 can reach 15 times higher than that of the pristine MoS 2 . The prominent improvement of HER performance for N-MoS 2 can be attributed to rich active sites, higher electron concentration around active sites, and ameliorative conductivity induced by N incorporation. The facile and controllable approach to activate MoS 2 for achieving high-level N-doping developed in this study can shed significant light on the preparation of heteroatoms-doped electrocatalytic materials.

AB - The development of nonprecious electrocatalysts with high hydrogen evolution reaction (HER) activity for water splitting is highly desirable but remains a significant challenge. Molybdenum disulfide (MoS 2 ) has been demonstrated as a good candidate; however, insufficient active sites along with poor conductivity significantly hinder the overall efficiency of MoS 2 . In this work, we present a method to activate commercial MoS 2 by high concentration nitrogen doping via a facile high-temperature treatment routine. The dominant N-doping mechanism is demonstrated to be an appropriate one-to-one substitution of sulfur atoms, which is confirmed by the approximate constancy between the atomic ratio of Mo/(S + N) and stoichiometric number of original MoS 2 . By controlling the activation time and temperature, the concentration of the doped nitrogen atoms can be tuned up to 41 atom %. The HER activity of the as-prepared materials was evaluated as electrode materials, showing that the catalytic activity is strongly correlated with the doped nitrogen concentration, and the catalytic current density of N-doped MoS 2 can reach 15 times higher than that of the pristine MoS 2 . The prominent improvement of HER performance for N-MoS 2 can be attributed to rich active sites, higher electron concentration around active sites, and ameliorative conductivity induced by N incorporation. The facile and controllable approach to activate MoS 2 for achieving high-level N-doping developed in this study can shed significant light on the preparation of heteroatoms-doped electrocatalytic materials.

UR - http://www.scopus.com/inward/record.url?scp=85065312965&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.9b00059

DO - 10.1021/acs.jpcc.9b00059

M3 - Journal article

AN - SCOPUS:85065312965

VL - 123

SP - 10917

EP - 10925

JO - The Journal of Physical Chemistry Part C

JF - The Journal of Physical Chemistry Part C

SN - 1932-7447

IS - 17

ER -