Amorphous‐Phase Tailoring of TiO ₂ –ZrO ₂ Interfacial Linkages Regulates Radical Pathways for Highly Selective Photocatalytic Methane Oxidation

Abstract

ABSTRACT Amorphous oxides offer unique short‐range order and coordination flexibility, yet their capacity to orchestrate interfacial radical chemistry and suppress over‐oxidation during photocatalytic methane to liquid conversion remains a critical frontier. Herein, we strategically construct TiO 2 –ZrO 2 architectures where the ZrO 2 phase is precisely tuned from amorphous (TiO 2 –ZrO 2 –A) to crystalline (TiO 2 –ZrO 2 –A800) to elucidate the governance of structural disorder over aerobic CH 4 functionalization. Multimodal characterizations—including x–ray absorption near‐edge structure (XANES)/extended x‐ray absorption fine structure (EXAFS), AC‐HRTEM, transient electron paramagnetic resonance (EPR), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT), reveal that the amorphous ZrO 2 phase enriches surface oxygen vacancies relative to its crystalline counterpart and establishes robust Ti–O–Zr interfacial linkages. This configuration enhances charge separation and supports higher effective steady‐state hole availability for efficient C–H bond activation while effectively tempering the flux of water‐derived reactive oxygen species. At room temperature TiO 2 –ZrO 2 –A achieves an exceptional liquid oxygenate selectivity of up to 98.2%, remarkably outperforming its crystalline analogue by resisting deep oxidation to CO 2 . Kinetic analyses reveal the rapid formation of *CH 3 and *CH 3 O intermediates, consistent with faster intermediate turnover and reduced overoxidation on the amorphous interface, consistent with DFT‐calculated barriers that favor methane activation over non‐selective reactive oxygen species (ROS) generation. These findings identify amorphous‐phase engineering as a kinetic valve for tuning pathways and selectivity in photocatalytic C–H transformations.