Carbonized Wood Decorated with Ternary Heterogeneous MoS<sub>2</sub>–MoP–Mo<sub>2</sub>C Nanoparticles for pH-Universal Hydrogen Evolution
Qiuyu Du, Yaoxing Wang, Xueqin Fan, Xueqi Li, Yingying Liu, Peng Jiao, Pengyu Xing, Ran Yin, Wentao Gan
Abstract
The assembly of diverse active materials significantly enhances the efficiency of the electrocatalytic hydrogen evolution reaction (HER). Herein, we prepare a three-phase composite structure electrocatalyst on carbonized wood, in which molybdenum carbide and molybdenum phosphide are attached to molybdenum sulfide nanosheets (MoS 2 –MoP–Mo 2 C@CW) through the hydrothermal method in combination with high-temperature calcination for a pH-universal HER. MoS 2 possesses abundant unsaturated coordination edge active sites, thus facilitating the adsorption and desorption of the hydrogen intermediate (H*). The synergistic effect between MoS 2, MoP featuring favorable electronic conductivity, and Mo 2 C holding strong adsorption of H* enhances the catalytic activity for the pH-universal HER. Moreover, the carbonized wood with a hierarchical porous structure and aligned microchannels accelerates mass transport during the HER. As a result, the molybdenum-based self-supported composite electrode exhibits outstanding HER performance with the low overpotentials of 46, 84, and 65 mV to achieve the current density of 10 mA cm –2 and the corresponding Tafel slopes of 57, 111 mV, and 63 mV dec –1 in alkaline, neutral, and acidic environments, respectively. MoS 2 –MoP–Mo 2 C@CW also shows a long-term durability of 200 h over a broad pH range at 10 mA cm –2 . This work provides an effective strategy for the development of multiphase carbonized wood-based electrocatalysts for the pH-universal HER.