Durable Electrocatalytic Reduction of Nitrate to Ammonia over Defective Pseudobrookite Fe<sub>2</sub>TiO<sub>5</sub>Nanofibers with Abundant Oxygen Vacancies
Hongting Du, Haoran Guo, Kaike Wang, Xiangning Du, Bayu Admasu Beshiwork, Shengjun Sun, Yongsong Luo, Qian Liu, Tingshuai Li, Xuping Sun
Abstract
Abstract We propose the pseudobrookite Fe 2 TiO 5 nanofiber with abundant oxygen vacancies as a new electrocatalyst to ambiently reduce nitrate to ammonia. Such catalyst achieves a large NH 3 yield of 0.73 mmol h −1 mg −1 cat. and a high Faradaic Efficiency (FE) of 87.6 % in phosphate buffer saline solution with 0.1 M NaNO 3 , which is lifted to 1.36 mmol h −1 mg −1 cat. and 96.06 % at −0.9 V vs. RHE for nitrite conversion to ammonia in 0.1 M NaNO 2 . It also shows excellent electrochemical durability and structural stability. Theoretical calculation reveals the enhanced conductivity of this catalyst and an extremely low free energy of −0.28 eV for nitrate adsorption at the presence of vacant oxygen.