Ligand Engineering in Nickel Phthalocyanine to Boost the Electrocatalytic Reduction of CO<sub>2</sub>
Kejun Chen, Maoqi Cao, Yiyang Lin, Junwei Fu, Hanxiao Liao, Yajiao Zhou, Hongmei Li, Xiaoqing Qiu, Junhua Hu, Xusheng Zheng, Mohsen Shakouri, Qunfeng Xiao, Yongfeng Hu, Jun Li, Jilei Liu, Emiliano Cortés, Min Liu
Abstract
Abstract Designing and synthesizing efficient molecular catalysts may unlock the great challenge of controlling the CO 2 reduction reaction (CO 2 RR) with molecular precision. Nickel phthalocyanine (NiPc) appears as a promising candidate for this task due to its adjustable Ni active‐site. However, the pristine NiPc suffers from poor activity and stability for CO 2 RR owing to the poor CO 2 adsorption and activation at the bare Ni site. Here, a ligand‐tuned strategy is developed to enhance the catalytic performance and unveil the ligand effect of NiPc on CO 2 RR. Theoretical calculations and experimental results indicate that NiPc with electron‐donating substituents (hydroxyl or amino) can induce electronic localization at the Ni site which greatly enhances the CO 2 adsorption and activation. Employing the optimal catalyst—an amino‐substituted NiPc—to convert CO 2 into CO in a flow cell can achieve an ultrahigh activity and selectivity of 99.8% at current densities up to −400 mA cm −2 . This work offers a novel strategy to regulate the electronic structure of active sites by ligand design and discloses the ligand‐directed catalysis of the tailored NiPc for highly efficient CO 2 RR.