Mediating Heterogenized Nickel Phthalocyanine into Single Ni-N3 Moieties for Improving Activity and Stability of Electrocatalytic Co2 Reduction

Abstract

The poor stability of heterogenized nickel phthalocyanine (NiPc) has hindered its application as a desirable catalyst for electrocatalytic CO2 reduction (CO2RR). Herein, mediating heterogenized NiPc (NiPc@NHCSs) into Ni-NC catalytic unit on nitrogen-doped hollow carbon nanospheres (NHCSs) through heat-treatment technology (Ni-NC/NHCSs-Y) was developed, which successfully optimized the stability of NiPc@NHCSs. The optimal catalyst with unsaturated Ni-N3 moieties and nitrogen-vacancy structure, displays a CO Faradaic efficiency ( ) of 98.57% and turnover frequency (3.75 s−1) at −0.87 V, and stable operation over 14 h (−0.82 V), superior to that of NiPc@NHCSs (  < 80%, stability < 1200 s). The stabilization mechanism and the temperature effect on the structure-activity relationship were systematically explored, and the strategy successfully steered to stabilize Ni-NC catalytic unit on different carbon substrate, while a Zn-CO2 rechargeable battery was designed, displaying a peak power density of 0.64 mW cm−2, and  of 91.45%.

Keywords: Electrocatalytic CO2 reduction, Nickel phthalocyanine, single Ni atom catalysts, Ni-N3 moieties, Zn-CO2 batteries