Zhichao Shen,Yanbin Qi,Wangxin Ge,Hongliang Jiang,Chunzhong Li
Urea electrooxidation reaction (UOR) plays an important role in environmental protection and energy regeneration. The extensively studied nickel-based catalysts exhibit good activity for UOR, but urea is more prone to be overelectrooxidized to another pollutant NOx– (x = 2, 3). Herein, the Cu/Ni-B interface catalyst is presented. The introduction of Cu significantly enhances the Faradaic efficiency of N2 (nearly 70% at 1.70 V versus RHE). Electrochemical tests and in situ Raman spectroscopy results show that the introduction of Cu significantly affects the density of OH* species on the catalyst in the UOR process. It is proposed that with a moderate decrease in OH* density, the catalyst can provide enough sites for urea molecules to allow simultaneous adsorption of the two N atoms, facilitating the process of N-N coupling to form N2. This work is also instructive for the design of electrocatalysts for other nucleophile electrooxidation reactions.
Semiconductor-based photoelectrochemistry commonly relies on efficient interactions between semiconductor surfaces and adsorbates for promoting charge transfer and efficiently activating inert bonds. But at the repulsive interfaces (e.g., between like-charged substrates and electrodes), such interactions cannot be achieved. Contrary to this paradigm, we find that the van der Waals interaction between a series of N-coordinated Cu complex cations and BiVO 4 photoanodes results in a high photovoltage of 0.53 V and charge transfer efficiency of 96%, along with the photocurrent density approaching the theoretical limit of BiVO 4 . This non-covalent interaction enables the universal generation of nitrogen-centered radicals from directly cleaving native N−H bonds and generates N–N coupling products with a Faradaic efficiency exceeding 96%. Its practical application is further demonstrated in an amplified photoelectrochemical reactor, generating a photocurrent of 409 mA and a yield rate of 6069 μmol h −1 for hydrazine production, which is competitive with most reported N−N coupling methods.
危险品化学品经营许可证（带存储）