Ambient ammonia synthesis via nitrite electroreduction over NiS 2 nanoparticles-decorated TiO 2 nanoribbon array.

Nitrite (NO ₂ ^- ), as a N-containing pollutant, widely exists in aqueous solution, causing a series of environmental and health problems. Electrocatalytic NO ₂ ^- reduction is a promising and sustainable strategy to remove NO ₂ ^- , meanwhile, producing high value-added ammonia (NH ₃ ). But the NO ₂ ^- reduction reaction (NO ₂ ^- RR) involves complex 6-electron transfer process that requires high-efficiency electrocatalysts to accomplish NO ₂ ^- -to-NH ₃ conversion. Herein, we report NiS ₂ nanoparticles decorated TiO ₂ nanoribbon array on titanium mesh (NiS ₂ @TiO ₂ /TM) as a fantastic NO ₂ ^- RR electrocatalyst for ambient NH ₃ synthesis. When tested in NO ₂ ^- -containing solution, NiS ₂ @TiO ₂ /TM achieves a satisfactory NH ₃ yield of 591.9 µmol h ^-1 cm ^-2 and a high Faradaic efficiency of 92.1 %. Besides, it shows remarkable stability during 12-h electrolysis test.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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