Built‐in Electric Field Triggered Interfacial Accumulation Effect for Efficient Nitrate Removal at Ultra‐Low Concentration and Electroreduction to Ammonia
Wu‐Ji Sun, Haoqing Ji, Lanxin Li, Hao‐Yu Zhang, Zhen‐Kang Wang, Jinghui He, Jianmei Lu
Abstract
Abstract A built‐in electric field in electrocatalyst can significantly accumulate higher concentration of NO 3 − ions near electrocatalyst surface region, thus facilitating mass transfer for efficient nitrate removal at ultra‐low concentration and electroreduction reaction (NO 3 RR). A model electrocatalyst is created by stacking CuCl (111) and rutile TiO 2 (110) layers together, in which a built‐in electric field induced from the electron transfer from TiO 2 to CuCl (CuCl_BEF) is successfully formed . This built‐in electric field effectively triggers interfacial accumulation of NO 3 − ions around the electrocatalyst. The electric field also raises the energy of key reaction intermediate *NO to lower the energy barrier of the rate determining step. A NH 3 product selectivity of 98.6 %, a low NO 2 − production of <0.6 %, and mass‐specific ammonia production rate of 64.4 h −1 is achieved, which are all the best among studies reported at 100 mg L −1 of nitrate concentration to date.