Atomic-Scale Pd on 2D Titania Sheets for Selective Oxidation of Methane to Methanol
Xingyang Wu, Qian Zhang, Wanfang Li, Botao Qiao, Ding Ma, Song Ling Wang
Abstract
Owing to maximally exposed active sites and a unique electronic structure, atomically thin two-dimensional semiconductor catalysts and atomic-scale metal co-catalysts are beyond their conventional bulk limit, especially for catalysis. Here, we report a two-dimensional titania (2DT) sheet-supported atomic-scale palladium (Pd1/2DT) via a stepwise solvothermal reaction and photochemical reduction approach. Such synthesized 2DT sheets have a layer structure, with a measured optical onset at ∼2.86 eV. An atomically thick 2D structure not only exhibits short-distance migration of photo-induced charge carriers but also provides more anchoring sites to stabilize atomic-scale Pd1 species, thus promoting the separation of charge carriers and stability of Pd1. This Pd1/2DT can catalyze methane conversion to methanol with a selectivity of 94% by using low-energy photons (λ > 420 nm) of solar light. Our work demonstrates that atomically low-dimensional catalysts can result in new and useful catalytic behaviors.