High-efficiency direct methane conversion to oxygenates on a cerium dioxide nanowires supported rhodium single-atom catalyst.

Direct methane conversion (DMC) to high value-added products is of significant importance for the effective utilization of CH4 to combat the energy crisis. However, there are ongoing challenges in DMC associated with the selective C-H activation of CH4. The quest for high-efficiency catalysts for this process is limited by the current drawbacks including poor activity and low selectivity. Here we show a cerium dioxide (CeO2) nanowires supported rhodium (Rh) single-atom (SAs Rh-CeO2 NWs) that can serve as a high-efficiency catalyst for DMC to oxygenates (i.e., CH3OH and CH3OOH) under mild conditions. Compared to Rh/CeO2 nanowires (Rh clusters) prepared by a conventional wet-impregnation method, CeO2 nanowires supported Rh single-atom exhibits 6.5 times higher of the oxygenates yield (1231.7 vs. 189.4 mmol gRh-1 h-1), which largely outperforms that of the reported catalysts in the same class. This work demonstrates a highly efficient DMC process and promotes the research on Rh single-atom catalysts in heterogeneous catalysis.