By merging electrocatalysis and nickel catalysis, a unified strategy has been successfully applied to achieve the decarboxylative crosscoupling of four types of α-oxocarboxylic acids and their derivatives with aryl trimethylammonium salts under mild conditions. Our strategy provides a practical way for preparing aryl ketones, amides, esters, or aldehydes.

Spinel structure Co 3 O 4 has been used as cathode catalysts for lithium−oxygen batteries, because of the structural stability, abundant oxygen vacancies, and adjustable Co 3+ /Co 2+ ratio. Most reports focused on adjusting the anion−cation ratio and coordination state in Co 3 O 4 to enhance its ORR and OER activities. Based on this, we interfered with the distribution of Co 2+ /Co 3+ by introducing Mn 3+ . Li 2 O 2 was detected as a discharge product by in situ characterization methods, but the charging voltage was only 3.25 V. During charge and discharge, Mncontaining Co 3 O 4 has a higher reversible shift of Co 3+ /Co 2+ , and this surface electron reconstitution effect leads to an extremely low overpotential (0.29 V). The surface electronic structure modified strategy and reversibility verification method could be a positive significance in the application of lithium−oxygen batteries, especially for reducing the use of noble metal catalysts.