Emerging applications of perovskite oxides in electrochemical reduction of carcinogenic nitrate to ammonia: a recent review

Abstract

Ammonia (NH₃) is essential for human endeavors, as around half of the world's food output depends on fertilizers derived from NH₃. Nonetheless, its industrial manufacturing demands substantial energy consumption and releases significant amounts of greenhouse gases, contributing to a variety of environmental concerns. Substantial ventures have been dedicated to creating an eco-friendly and sustainable method for synthesizing ammonia using renewable energy. Catalysts are pivotal in both chemical and electrochemical reactions. Hence, the creation of catalysts exhibiting increased efficiency and durability, obtained from readily accessible Earth materials, holds immense significance. Perovskite oxides, recognized for their significant flexibility in composition and structural design, demonstrate versatile electrocatalytic abilities across a variety of redox reactions. However, a comprehensive review addressing the most recent advancements in the electrochemical reduction of nitrate (NO₃⁻) to NH₃ catalyzed by perovskite oxides has been absent until now. This timely review provides readers with a thorough comprehension and up-to-date perspectives on progress made in enhancing the electrocatalytic potential of perovskite oxides in the electrochemical reduction of nitrate (eNO₃RR) to ammonia. We have also explored different strategies capable of enhancing the catalytic efficacy of perovskite oxides. A specific emphasis is placed on understanding how the interplay between perovskite and oxygen vacancies contributes to the improved efficiency of NO₃⁻ reduction to NH₃. Finally, this review outlines present challenges and upcoming avenues for developing more efficient catalysts based on perovskite compounds.