Zhou, S., Ma, W., Anjum, U., Kosari, M., Xi, S., Kozlov, S. M., & Zeng, H. C. (2023). Strained few-layer MoS2 with atomic copper and selectively exposed in-plane sulfur vacancies for CO2 hydrogenation to methanol. Nature Communications, 14(1). https://doi.org/10.1038/s41467-023-41362-y
Abstract:
In-plane sulfur vacancies (Sv) in molybdenum disulfide (MoS2) were newly unveiled for CO2 hydrogenation to methanol, whereas edge Sv were found to facilitate methane formation. Thus, selective exposure and activation of basal plane is crucial for methanol synthesis. Here, we report a mesoporous silica-encapsulated MoS2 catalysts with fullerene-like structure and atomic copper (Cu/MoS2@SiO2). The main approach is based on a physically constrained topologic conversion of molybdenum dioxide (MoO2) to MoS2 within silica. The spherical curvature enables the generation of strain and Sv in inert basal plane. More importantly, fullerene-like structure of few-layer MoS2 can selectively expose in-plane Sv and reduce the exposure of edge Sv. After promotion by atomic copper, the resultant Cu/MoS2@SiO2 exhibits stable specific methanol yield of 6.11 molMeOH molMo–1 h–1 with methanol selectivity of 72.5% at 260 °C, much superior to its counterparts lacking the fullerene-like structure and copper decoration. The reaction mechanism and promoting role of copper are investigated by in-situ DRIFTS and in-situ XAS. Theoretical calculations demonstrate that the compressive strain facilitates Sv formation and CO2 hydrogenation, while tensile strain accelerates the regeneration of active sites, rationalizing the critical role of strain.
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Attribution 4.0 International (CC BY 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research (A*STAR) - Low Carbon Energy Research Finding Initiative (LCERFI01-0033 | U2102d2006)
Grant Reference no. : U2102d2006
This research / project is supported by the National Research Foundation - Campus forResearch Excellence and Technological Enterprise (CREATE C4T Pro-gram)
Grant Reference no. :