Boosting CO 2 Hydrogenation to Methanol over Monolayer MoS 2 Nanotubes by Creating More Strained Basal Planes.

The controlled creation, selective exposure, and activation of more basal planes while simultaneously minimizing the generation and exposure of edge sites are crucial for accelerating methanol synthesis from CO 2 hydrogenation over MoS 2 catalysts but remain a bottleneck. Here, we report a facile method to fabricate heteronanotube catalysts with single-layer MoS 2 coaxially encapsulating the carbon nanotubes (CNTs@MoS 2 ) through host-guest chemistry. Inheriting the long tubular structure of CNTs, the grown MoS 2 nanotubes exhibit significantly more basal planes than bulk MoS 2 crystals. More importantly, the tubular curvature not only promotes strain and sulfur vacancy (Sv) generation but also preferentially exposes more in-plane Sv while limiting edge Sv exposure, which is conducive to methanol synthesis. Both the strain and layer number of MoS 2 can be easily and finely adjusted by altering CNT diameter and quantity of precursors. Remarkably, CNTs@MoS 2 with monolayer MoS 2 and maximum strain displayed methanol selectivity of 78.1% and methanol space time yield of 1.6 g g MoS 2 -1 h -1 at 260 °C and GHSV of 24000 mL g cat. -1 h -1 , representing the best results to date among Mo-based catalysts. This study provides prospects for novel catalyst design by synthesizing coaxial tubular heterostructure to create additional catalytic sites and ultimately enhance conversion and selectivity.