Fabricating 0D/1D/2D Ag/Carbon Nanotube/WS2 Heterostructure for Boosted Hydrogen Evolution Reaction in Akaline and Acidic Conditions

The development of electrocatalysts suitable for efficient hydrogen evolution in harsh conditions, such as acidic and/or alkaline solutions, is quite important for the production of a clean energy source, hydrogen (H-2), through electrochemical water splitting. Herein, we designed a zero/one/two-dimensional (0D/1D/2D) heterostructured catalyst (namely, Ag/MCNT/WS2) for efficient hydrogen evolution reaction (HER) in both acidic and alkaline environments. Due to the enrichment of 1T phase WS2, good electrical conductivity of carbon nanotubes (CNTs) and Ag nanoparticles, as well as numerous multidimensional interfaces, the 0D/1D/2D heterostructured catalyst showed a significantly enhanced HER electrocatalytic performance as compared with WS2 and the binary composite Ag/MCNT. Typically, Ag/MCNT/WS2 showed a much lower overpotential of 182.0 mV (in 0.5 mol L-1 H2SO4) and 218.9 mV (1 mol L-1 KOH) than WS2 (262.0 and 277.9 mV, respectively) for achieving a current density of 10 mA cm(-2). Additionally, the electrochemically active surface area (ECSA) of Ag/MCNT/WS2 reached 437.5 and 498.0 cm(2) in alkaline and acidic solutions, respectively. These values were almost 15 times higher than those of WS2. This work provides an efficient strategy for boosting the electrocatalytic performance of WS2 for HER through constructing multidimensional interfaces with conductive CNTs and Ag nanoparticles.