Exploring 1t/2h Mos2 Quantum Dots Modified 2d Copx Nanosheets for Efficient Electrocatalytic Hydrogen Evolution Reaction

Abstract

The exploration of 0D/2D heterojunction for electrocatalysis has attracted ascending attention due to their intrinsic strengths comprising the designed contact interface, reduced distance for charges and intermediates transportation, and abundant active sites for reactions are propitious to various electrocatalytic reactions. Transition metal sulfides and phosphides have been considered as ideal electrocatalysts for hydrogen evolution reaction (HER) owing to the abundantly exposed edges with desirable physiochemical properties. Herein, a novel combination route where 0D molybdenum sulfide quantum dots (MoS2 QDs) are uniformly anchored on the 2D CoPx nanosheets is proposed. MoS2 QDs and CoPx were prepared via the hydrothermal method and mixed with different ratios (Mo:Co ratios of 2:1, 1:1, and 1:2) and annealed under different temperatures to modulate their application in acidic HER processes. Specifically, 2Mo/1Co exhibited advanced performance for HER in 0.5 M H2SO4 solution and required 14 mV to deliver 10 mA cm-2 and revealed a descended Tafel slope of 75.42 mV dec-1 with 240 h stability except obvious deactivation. The successful design and construction of 0D/2D mixed-dimensional materials would broaden the application of MoS2 and CoPx for electrocatalytic hydrogen evolution.

Keywords: 2D nanosheets, molybdenum sulfide quantum dots, cobalt phosphide, hydrogen evolution reaction