Electrophoretic Deposition of MoSe2-MoOx Nanosheets for Enhanced Electrocatalytic Hydrogen Evolution Reaction

Herein, we report an electrophoretically prepared electrode based on photosensitive 2D-MoSe2-MoOx for electrocatalytic hydrogen evolution reaction (HER). Large-area and binder-free electrodes show rapid electrocatalysis due to suitable intrinsic properties such as low charge-transfer resistance, an onset potential of -160 mV versus RHE (reversible hydrogen electrode), an overpotential of about -210 mV versus RHE at -10 mA/cm(2), and a double-layer capacitance of 16.2 mF/cm(2). Furthermore, injection of photogenerated electrons leads to an onset potential as low as -90 mV versus RHE and an overpotential of -150 mV versus RHE under the illumination of visible light. The photocathode demonstrates excellent photoresponsivity in the spectral range 390-670 nm. The electrode exhibits photocurrents of 0.42 mA/cm(2) at 0 mV and 10.19 mA/cm(2) at -240 mV versus RHE under the illumination of 670 nm, 30 mW/cm(2) light. Owing to optimized light-harvesting abilities, 2D-MoSe2-MoOx demonstrates a high photoresponsivity of 0.34 A/W (1.4 x 10(-2) A/W) and an external quantum efficiency of 62.9% (2.6%) at -240 mV (0 mV) versus RHE. Finally, the photocathode encourages the use of sunlight for increasing the rate of electrocatalytic HER for the production of clean energy.

Automated summary

An electrophoretically prepared electrode based on photosensitive 2D-MoSe2-MoOx is reported for electrocatalytic hydrogen evolution reaction, demonstrating rapid electrocatalysis and excellent photoresponsivity under visible light illumination. Owing to its optimized light-harvesting abilities, the electrode shows a high external quantum efficiency and encourages the use of sunlight for clean energy production.