Revealing the promotion of carbonyl groups on vacancy stabilized Pt4/nanocarbons for propane dehydrogenation

Nanocarbons are promising supports for Pt clusters applied in propane dehydrogenation (PDH), owing to their large surface areas and tunable chemical properties. The vacancies and oxygen-containing groups (OCGs) in nanocarbons can enhance catalytic performance by tailoring the coordination environment of Pt clusters. Herein, 46 nanocarbons with coexisting vacancies and OCGs were designed to support Pt clusters, of which the influences on PDH were revealed by density functional theory calculations. Nanocarbons with divacancies (V2) and C=O edge groups were screened out as the most appropriate support for Pt clusters in PDH. Due to the V2, tetrahedral Pt clusters were distorted into three-layered configurations, contributing to enhanced binding strength and a favorable reactive pathway starting from the methylene group in propane. This changed the rate-determining step to the first C-H bond scission with a low energy barrier. The introduction of C=O edge groups coexisting with V2 further improved the stabilization of Pt clusters, resulting from the increased electron transfer from Pt atoms to C atoms. The abilities to break C-H bonds and inhibit C-C bond cracking were also enhanced as compared to the nanocarbons with only V2. Therefore, this work provides references on the regulation of vacancies and OCGs in carbon-based catalysts.

Automated summary

The vacancies and oxygen-containing groups in nanocarbons can enhance the catalytic performance of supported Pt clusters in propane dehydrogenation. In this study, nanocarbons with coexisting vacancies and oxygen-containing groups were designed and their influences on PDH were investigated by density functional theory calculations. Nanocarbons with divacancies and C=O edge groups were found to be the most suitable support for Pt clusters in PDH, resulting in enhanced binding strength and improved stabilization of Pt clusters.