Xialiang Li, Xiaotong Jin, Yuchen Cao, Jianqiu Zhu, Delong Duan, Qian‐Cheng Luo, Bin Lv, Yuhan Xu, Yan‐Zhen Zheng, Wei Zhang, Ran Long, Linjuan Zhang, Rong‐Zhen Liao, Rui Cao
Electrocatalytic oxygen reduction reaction (ORR) near its thermodynamic equilibrium potential is vital for efficient energy conversion. However, low-valent metal ions generated at high cathodic potentials are typically required to achieve effective O 2 activation. Herein we report O 2 activation promoted by a Sc 3+ -hung Co III corrole, which realizes markedly boosted ORR electrocatalysis. Co III corrole 1 with an appended crown ether substituent was synthesized. By grabbing a Sc 3+ ion, the ORR overpotential with Sc 3+ -hung 1 decreased by 1.0 V in acetonitrile and 170 mV in 0.5 M H 2 SO 4 solutions. Importantly, Sc 3+ -hung 1 achieved an ORR half-wave potential of 0.78 V vs RHE in 0.5 M H 2 SO 4 solutions with a transferred electron number of 3.87. Our results suggest that the hanging Sc 3+ promotes O 2 binding and activation at the Co III ion of 1 to generate a Co III –superoxo–Sc 3+ corrole cation radical and assists subsequent O–O bond cleavage by accepting the leaving hydroxide.