Highly active and stable bifunctional electrocatalysts for overall water splitting are important for clean and renewable energy technologies. The development of energy-saving electrocatalysts for hydrogen evolution reaction (HER) by replacing the sluggish oxygen evolution reaction (OER) with a thermodynamically favorable electrochemical oxidation (ECO) reaction has attracted increasing attention. In this study, a self-supported, hierarchical, porous, nitrogen-doped carbon (NC)@CuCo 2 N x /carbon fiber (CF) is fabricated and used as an efficient bifunctional electrocatalyst for both HER and OER in alkaline solutions with excellent activity and stability. Moreover, a two-electrode electrolyzer is assembled using the NC@CuCo 2 N x /CF as an electrocatalyst at both cathode and anode electrodes for H 2 production and selective ECO of benzyl alcohol with high conversion and selectivity. The excellent electrocatalytic activity is proposed to be mainly due to the hierarchical architecture beneficial for exposing more catalytic active sites, enhancing mass transport. Density functional theoretical calculations reveal that the adsorption energies of key species can be modulated due to the synergistic effect between CoN and CuN. This work provides a reference for the development of high-performance bifunctional electrocatalysts for simultaneous production of H 2 and high-value-added fine chemicals.

Paired electrosynthesis is a promising technology with the potential to generate value-added products at both electrodes in a cost-effective manner. Herein, 3D vanadium nitride (VN) and Pd/VN hollow nanospheres are successfully fabricated and coupled to carry out simultaneous electrocatalytic oxidation (ECO) and electrocatalytic hydrogenation (ECH) of 5-hydroxymethylfurfural (HMF) into 2, 5-furandicarboxylic acid (FDCA) and 2,5-bishydroxymethyl-tetrahydrofuran (DHMTHF), respectively. VN shows excellent ECO performance with high HMF conversion (≥98%), FDCA selectivity (≥96%), and faradaic efficiency (≥84%) after a stability test, and Pd/VN achieves high ECH selectivity for DHMTHF at ≥88% and an HMF conversion of ≥90%, with a faradaic efficiency of ≥86%. VN and Pd/VN incorporated into a membrane electrode assembly in a paired electrolysis system shows potential for large-scale biomass conversion and upgrading. Theoretical calculations reveal that the higher performance of VN for the production of ECO can be attributed to its lower d-band center level relative to the Fermi level compared to that of V 2 O 5 , which favors HMF chemisorption and activation. This study paves the way for developing paired electrosynthesis technologies with the potential for biomass utilization and energy conversion.

The on-site production of ozone via electrochemical water electrolysis has attracted increasing interest because of its security and efficiency. However, the underlying mechanisms of the facet effect and lattice oxygen...

Selective electrocatalytic oxidation (ECO) of benzyl alcohol to benzoic acid or benzaldehyde over 1.0 h-Ni(OH)2 with excellent conversion, selectivity, and stability in a two compartment H cell is presented.