Bimetallic Interface of RuCu Hollow Nanostructures Combined with B₄C for Enhancing Electrocatalysis on Nitrate Reduction

A technology for nitrate reduction is required urgently because of serious nitrate pollution and ammonia deficiency. RuCu was usually prepared and tailored with facile methods and had a high performance on nitrate reduction because of the high activity of Ru on nitrate reduction and the inhibition of hydrogen evolution by Cu. Hence, constructing RuCu hollow nanoparticles is a possible way to obtain a high atomic utilization, and the interface or porous structure would bring high activity on electrocatalysis. Herein, RuCu hollow nanoparticles were prepared by a hydrothermal reaction and then loaded on a B4C substrate to construct the RuCu/B4C catalysts that exhibited high activity on nitrate reduction reaction (NO3RR) to produce ammonia. The results showed that the ammonia yield rate on the RuCu/B4C catalyst was 55.60 ± 1.46 mg h–1 mgcat–1, and the Faradaic efficiency (FE) was as high as 92.79 ± 1.56% at −0.6 VRHE. Further studies suggested that the synergistic effect between B4C and RuCu in the catalyst promoted their performance. In detail, RuCu nanoparticles with hollow structures served as the main active centers to transform NO3– into NH3, cooperating with the enhancement of NO3– adsorption by the support B4C. Therefore, RuCu/B4C synergistically achieved the high yield performance of ammonia.