Enhanced coking and sintering resistant in dry reforming of methane over CoRh alloy confined in mesoporous silica

Dry reforming of methane (DRM) to produce syngas can effectively address environmental issues caused by the greenhouse effect. Nevertheless, sintering and coking of catalysts under high-temperature operating conditions continue to be critical challenges that hinder practical applications. Herein, this work develops a CoRh alloy catalyst (Co 7 Rh 3 /DMS) confined in dendritic mesoporous silica (DMS) that displays an 89.1 % CH 4 and 92.4 % CO 2 conversion, approaching the thermodynamic equilibrium limit. Under a continuous operation at 800 °C for 100 h, the Co 7 Rh 3 /DMS catalyst shows a CH 4 and CO 2 deactivation rates of merely 0.022 %·h −1 and 0.011 %·h −1 , respectively, with negligible coke formation (<0.1 wt%) and metal sintering. Notably, the surface spatial confined structures of DMS effectively suppress the migration and agglomeration of active sites. Comprehensive mechanistic investigations indicate that the synergistic mechanism of CoRh alloy reduces the CH 4 dissociation energy barrier and promotes CO 2 activation, thereby facilitating the in-situ elimination of carbonaceous precursors. This work provides a rational design strategy for advancing the efficient resource utilization of greenhouse gases.