A Copper–Zinc Cyanamide Solid-Solution Catalyst with Tailored Surface Electrostatic Potentials Promotes Asymmetric N-Intermediate Adsorption in Nitrite Electroreduction
Jiacheng Jayden Wang, Jiacheng Jayden Wang, Huong Thi Bui, Xunlu Wang, Zhuoran Lv, Huashuai Hu, Shuyi Kong, Zhiqiang Wang, Lijia Liu, Wei Chen, Hui Bi, Minghui Yang, Tore Brinck, Jiacheng Wang, Jiacheng Wang, Fuqiang Huang
Abstract
High Resolution Image Download MS PowerPoint Slide The electrocatalytic nitrite reduction (NO 2 RR) converts nitrogen-containing pollutants to high-value ammonia (NH 3 ) under ambient conditions. However, its multiple intermediates and multielectron coupled proton transfer process lead to low activity and NH 3 selectivity for the existing electrocatalysts. Herein, we synthesize a solid-solution copper–zinc cyanamide (Cu 0.8 Zn 0.2 NCN) with localized structure distortion and tailored surface electrostatic potential, allowing for the asymmetric binding of NO 2 – . It exhibits outstanding NO 2 RR performance with a Faradaic efficiency of ∼100% and an NH 3 yield of 22 mg h –1 cm –2, among the best for such a process. Theoretical calculations and in situ spectroscopic measurements demonstrate that Cu–Zn sites coordinated with linear polarized [NCN] 2– could transform symmetric [Cu–O–N–O–Cu] in CuNCN-NO 2 – to a [Cu–N–O–Zn] asymmetric configuration in Cu 0.8 Zn 0.2 NCN-NO 2 –, thus enhancing adsorption and bond cleavage. A paired electro-refinery with the Cu 0.8 Zn 0.2 NCN cathode reaches 2000 mA cm –2 at 2.36 V and remains fully operational at industrial-level 400 mA cm –2 for >140 h with a NH 3 production rate of ∼30 mg NH3 h –1 cm –2 . Our work opens a new avenue of tailoring surface electrostatic potentials using a solid-solution strategy for advanced electrocatalysis.