Boosting photothermal catalytic non-oxidative methane coupling by high-density frustrated Lewis pairs in Ag/InOxHy

Abstract

The photocatalytic nonoxidative coupling of methane (CH₄) is crucial for sustainable energy production and chemical synthesis, however, a key challenge in advancing this process lies in the development of efficient and highly selective catalytic systems. In this study, we employ an in situ thermally induced strategy to promote the in-situ growth of oxygen vacancies (V_O) for constructing a high-density In-V_O-In-OH frustrated Lewis pairs (FLP) on Ag/In(OH)₃-InOOH (Ag/InO_xH_y). Our results demonstrate that FLP can effectively polarize C–H bonds, while Ag nanoparticles serve as electron acceptors, significantly reducing the recombination of photogenerated carriers and enhancing the catalytic performance of methane coupling. Benefiting from the high density of FLP and photothermal synergistic effect, we achieve a remarkable C₂H₆ yield of 339.2 μmol g_cat⁻¹h⁻¹ over Ag/InO_xH_y in a flow methane atmosphere. Notably, in-situ electron paramagnetic resonance analysis not only validates this innovative strategy but also reveals a new mechanism of oxygen vacancy recycling which showcases its great potential to advance other photocatalytic processes.