Lewis acid (Ni²⁺, Co^2+/3+or Zn²⁺) modified electron-deficient Ir⁴⁺in IrO₂/CuO for promoting methane oxidation to ethanol and methanol

This work delineates the first attempt to tune the product distribution between methanol and ethanol in the direct oxidation of methane reaction by incorporating Lewis acids Ni²⁺, Co^2+/3+or Zn²⁺into IrO₂/CuO. The electrophilicity of Ir⁴⁺and the (LAS-BAS)/LAS ratio (LAS: Lewis acid sites, BAS: Brønsted acid sites) are demonstrated to be two reactivity descriptors motivating CH₄activation and ethanol formation, respectively. Electron-deficient Ir⁴⁺motivates enriched *CH₃concentration and subsequent C-C coupling for C₂H₄formation, while the Lewis acid promotes ethanol formation from C₂H₄involving lattice O and H₂O. The ethanol selectivity presents a quasi-linear relationship with (LAS-BAS)/LAS.