High-efficiency electrocatalytic nitrite reduction toward ammonia synthesis on CoP@TiO2 nanoribbon array
Xun He, Zixiao Li, Jie Yao, Kai Dong, Xiuhong Li, Long Hu, Shengjun Sun, Zhengwei Cai, Dongdong Zheng, Yongsong Luo, Binwu Ying, Mohamed S. Hamdy, Lisi Xie, Qian Liu, Xuping Sun
Abstract
Electrochemical reduction of nitrite (NO 2 − ) can satisfy the necessity for NO 2 − contaminant removal and deliver a sustainable pathway for ammonia (NH 3 ) generation. Its practical application yet requires highly efficient electrocatalysts to boost NH 3 yield and Faradaic efficiency (FE). In this study, CoP nanoparticle-decorated TiO 2 nanoribbon array on Ti plate (CoP@TiO 2 /TP) is verified as a high-efficiency electrocatalyst for the selective reduction of NO 2 − to NH 3 . When measured in 0.1 M NaOH with NO 2 − , the freestanding CoP@TiO 2 /TP electrode delivers a large NH 3 yield of 849.57 μmol h −1 cm −2 and a high FE of 97.01% with good stability. Remarkably, the subsequently fabricated Zn–NO 2 − battery achieves a high power density of 1.24 mW cm −2 while delivering a NH 3 yield of 714.40 μg h −1 cm −2 .