Synthesis of 3D Porous Cu Nanostructures on Ag Thin Film Using Dynamic Hydrogen Bubble Template for Electrochemical Conversion of CO2 to Ethanol.

Cu-based nanomaterials have been widely considered to be promising electrocatalysts for the direct conversion of CO2 to high-value hydrocarbons. However, poor selectivity and slow kinetics have hindered the use of Cu-based catalysts for large-scale industrial applications. In this work, we report on a tunable Cu-based synthesis strategy using a dynamic hydrogen bubble template (DHBT) coupled with a sputtered Ag thin film for the electrochemical reduction of CO2 to ethanol. Remarkably, the introduction of Ag into the base of the three-dimensional (3D) Cu nanostructure induced changes in the CO2 reduction reaction (CO2RR) pathway, which resulted in the generation of ethanol with high Faradaic Efficiency (FE). This observation was further investigated through Tafel and electrochemical impedance spectroscopic analyses. The rational design of the electrocatalyst was shown to promote the spillover of formed CO intermediates from the Ag sites to the 3D porous Cu nanostructure for further reduction to C2 products. Finally, challenges toward the development of multi-metallic electrocatalysts for the direct catalysis of CO2 to hydrocarbons were elucidated, and future perspectives were highlighted.

Highly boosted gas diffusion for enhanced electrocatalytic reduction of N2 to NH3 on 3D hollow Co-MoS2 nanostructures.

Transition metal chalcogenide MoS2 catalysts are highly selective for the electrochemical reduction of dinitrogen (N2) to ammonia (NH3) in aqueous electrolytes. However, due to the low solubility of N2 in water, limited N2 diffusion and mass transport have heavily restricted the yield and the faradaic efficiency (FE). Here, we have demonstrated a highly efficacious assembled gas diffusion cathode with hollow Co-MoS2/N@C nanostructures to significantly improve the electrochemical reduction of N2 to NH3. Our results revealed that the synthesized Co-MoS2 heterojunctions with abundant graphitic N groups exhibited a superb NH3 yield of 129.93 µg h-1 mgcat-1 and a high faradaic efficiency of 11.21% at -0.4 V vs. the reversible hydrogen electrode (RHE), as well as excellent selectivity and stability. The strategy described in this study offers new inspiration to design high-performance electrocatalyst assemblies for the sustainable environmental and energy applications.