| Abstract |
The world can hope to stave off the escalationof the globalpollution with the help of effective deNO( x ) catalysis. This study shows a novel route of selective transformationof the pollutant nitrate to a useful chemical of ammonia over metal-organicframework-derived bimetallic nanoalloy catalysts. A translation ofthis technology can be a bellwether to the circular economy model. The selective electrocatalytic reduction of nitrate pollutantsinto valuable ammonia products has gained significant momentum thanksto the emerging circular economy model. However, this technology suffersfrom poor selectivity, low Faradic efficiency, and a competing parallelhydrogen evolution reaction. In this regard, the use of nanoalloysoffers a promising approach to fine-tune the electronic structureby shifting the position of the d-band center and modulating the interactionwith nitrate and other reaction intermediates and thus enhance theselectivity of desirable products, which may not be accessible overa pristine single metallic active site. Herein, we have systematicallydoped Cu (d(9)s(2)) by Ni (d(8)s(2)) and Zn (d(10)s(2)) to produce Cu0.85Ni0.15/C and Cu0.85Zn0.15/C, respectively,from the corresponding bimetallic metal-organic framework materials.A thorough investigation of electrocatalytic nitrate reduction overthe as-synthesized nanomaterials was done by studying the productyield, selectivity, Faradic efficiency, reaction order, rate, andactivation energy. The synthesized carbon-supported nanoalloy of Cu0.85Zn0.15/C outperformed both Cu0.85Ni0.15/C and Cu/C, and the superiority was rationalizedby the first-principles calculation, which unveiled the significanceof the modulation of the d-bands in influencing the interaction ofnitrate and other reaction intermediates with the surface, therebyenhancing the selectivity and catalytic efficacy. |