The kinetics and potential dependence of the hydrogen evolution reaction optimized for the basal-plane Te vacancy site of MoTe₂
Md Delowar Hossain, Zhenjing Liu, Hongwei Liu, Abhishek Tyagi, Faisal Rehman, Jingwei Li, Mohammadreza Amjadian, Yuting Cai, William A. Goddard III, Zhengtang Luo
Abstract
Electrocatalysis at the edge sites of transition-metal dichalcogenides has been well studied, particularly for the hydrogen evolution reaction (HER). Here, we explore instead the HER activity on the basal plane of MoTe₂ by creating anion vacancies via computational predictions followed by experimental validation. Using the grand canonical potential kinetics method, we predict that overpotentials of 535 and 565 mV can achieve a current density of 10 mA cm⁻² for 1T′-MoTe₂ and 2H-MoTe₂ containing 1.14 x 10¹⁴ cm⁻² and 3.45 x 10¹³ cm⁻² Te vacancies, respectively. This is in good agreement with experimental overpotentials of 561 and 634 mV for 1T′-MoTe₂ and 2H-MoTe₂ containing similar vacancies ( 1.28 x 10¹⁴ cm⁻² and 3.54 x 10¹³ cm⁻², respectively). Furthermore, we used Ar plasma treatment to increase the Te vacancy on the basal plane and found an optimal vacancy concentration of 3.18 x 10¹⁴ cm⁻² for 1T′-MoTe₂ and 1.02 x 10¹⁴ cm⁻² for 2H-MoTe₂. Increasing or decreasing the vacancy concentrations from this level further reduces HER performance.
Group Members
Hossain, M. D., Liu, Z., Liu, H., Tyagi, A., Rehman, F., Li, J., Amjadian, M., Cai, Y., III, W. A. G., & Luo, Z. (2023). The kinetics and potential dependence of the hydrogen evolution reaction optimized for the basal-plane Te vacancy site of MoTe₂. *Chem Catalysis*, *3*(1), Art. No. 100489. https://doi.org/10.1016/j.checat.2022.100489