Platinum‐ and CuOx‐Decorated TiO2 Photocatalyst for Oxidative Coupling of Methane to C2 Hydrocarbons in a Flow Reactor

Abstract

Oxidative coupling of methane (OCM) is considered one of the most promising catalytic technologies to upgrade methane. However, C 2 products (C 2 H 6/C 2 H 4) from conventional methane conversion have not been produced commercially owing to competition from overoxidation and carbon accumulation at high temperatures. Herein, we report the codeposition of Pt nanoparticles and CuO x clusters on TiO 2 (PC‐50) and use of the resulting photocatalyst for OCM in a flow reactor operated at room temperature under atmospheric pressure for the first time. The optimized Cu 0.1 Pt 0.5/PC‐50 sample showed a highest yield of C 2 product of 6.8 μmol h−1 at a space velocity of 2400 h−1, more than twice the sum of the activity of Pt/PC‐50 (1.07 μmol h−1) and Cu/PC‐50 (1.9 μmol h−1), it might also be the highest among photocatalytic methane conversions reported so far under atmospheric pressure. A high C 2 selectivity of 60 % is also comparable to that attainable by conventional high‐temperature (>943 K) thermal catalysis. It is proposed that Pt functions as an electron acceptor to facilitate charge separation, while holes could transfer to CuO x to avoid deep dehydrogenation and the overoxidation of C 2 products.