Electrocatalytic water splitting offers a promising way for hydrogen production with near-zero emissions. Carbides, such as molybdenum carbides (Mo₂C), are promising materials for hydrogen evolution reaction (HER) but still suffer from poor intrinsic water activation properties. Here, we developed a plasmon-induced local electric field (PILEF) strategy to solve this barrier. Silver (Ag) nanoparticles decorated Mo₂C nanosheets (Ag/Mo₂C) were successfully prepared by electrostatic adsorption. The visible light excited the PILEF on Ag/Mo₂C remarkably reducing the activation energy by 92.7 kJ·mol⁻¹ from 147.3 kJ·mol⁻¹ of Mo₂C to 54.6 kJ·mol⁻¹. As a result, the plasmonic Ag/Mo₂C significantly enhances ~ 2.3-fold of the current density from 2.8 mA·cm⁻² of Mo₂C to 6.5 mA·cm⁻² at −3 V vs. RHE and reduces the overpotential by 104 mV from 403 mV of dark state to 299 mV of light state at the current density of 10 mA·cm⁻², achieving better performance than reported catalysts. This research demonstrates that PILEF enhances HER activities, offering a potential strategy for boosting the intrinsic activities of catalysts.

The use of gas diffusion electrode (GDE) based flow cell can realize industrial-scale CO₂ reduction reactions (CO₂RRs). Controlling local CO₂ and CO intermediate diffusion plays a key role in CO₂RR toward multi-carbon (C₂₊) products. In this work, local CO₂ and CO intermediate diffusion through the catalyst layer (CL) was investigated for improving CO₂RR toward C₂₊ products. The gas permeability tests and finite element simulation results indicated CL can balance the CO₂ gas diffusion and residence time of the CO intermediate, leading to a sufficient CO concentration with a suitable CO₂/H₂O supply for high C₂₊ products. As a result, an excellent selectivity of C₂₊ products ~ 79% at a high current density of 400 mA·cm⁻² could be obtained on the optimal 500 nm Cu CL (Cu500). This work provides a new insight into the optimization of CO₂/H₂O supply and local CO concentration by controlling CL for C₂₊ products in CO₂RR flow cell.

Converting carbon dioxide (CO₂) into value-added chemicals by CO₂ reduction has been considered as a potential way to solve the current energy crisis and environmental problem. Among the methods of CO₂ reduction, the electrochemical method has been widely used due to its mild reaction condition and high reaction efficiency. In the electrochemical reduction system, the CO₂ electrocatalyst is the most important part. Although many CO₂ electrocatalysts have been developed, efficient catalysts with high activity, selectivity and stability are still lacking. Copper sulfide compound, as a low-toxicity and emerging material, has broad prospects in the field of CO₂ reduction due to its unique structural and electrochemical properties. Much progress has been achieved with copper sulfide nanocrystalline and the field is rapidly developing. This paper summarizes the preparation, recent progress in development, and factors affecting the electrocatalytic CO₂ reduction performance with copper sulfide compound as a catalyst. Prospects for future development are also outlined, with the aim of using copper sulfide compound as a highly active and stable electrocatalyst for CO₂ reduction.