Boosting oxygen vacancies by modulating the morphology of Au decorated InO with enhanced CO hydrogenation activity to CHOH.

CO hydrogenation to methanol has become one of the most promising ways for CO utilization, however, the CO conversion rate and methanol selectivity of this reaction still need to be improved for industrial application. Here we investigated the structure-activity relationship for CO conversion to methanol of InO-based catalysts by modulating morphology and decorating Au. Three different Au/InO catalysts were prepared, their activity follow the sequence of Au/InO-nanosphere (Au/InO-NS) > Au/InO-nanoplate (Au/InO-NP) > Au/InO-hollow microsphere (Au/InO-HM). Au/InO-NS exhibited the best performance with good CO conversion of 12.7%, high methanol selectivity of 59.8%, and large space time yield of 0.32 g/(hr·g) at 300°C. The high performance of Au/InO-NS was considered as the presence of Au. It contributes to the creation of more surface oxygen vacancies, which further promoted the CO adsorption and facilitated CO activation to form the formate intermediates towards methanol. This work clearly suggests that the activity of InO catalyst can be effective enhanced by structure engineering and Au decorating.