Recent progress in the design of dry reforming catalysts supported on low-dimensional materials

Abstract

Dry reforming of methane (DRM) is a technique used to produce synthesis gas via a reaction with carbon dioxide. The process requires a catalyst due to the high activation energy. Low-dimensional (Low-D) materials are excellent catalyst supports for DRM due to their chemical stability, large surface area, porous structure, and tunable properties. The review examines, for the first time, the investigations on DRM by catalysts supported on low-D materials and discusses significant advances and breakthroughs in catalyst design and process performance. High catalytic activity can be achieved with carbon nanotubes (CNTs) as catalyst supports when the active metals are inside the tube walls compared to outside the walls. Ni and Co have been shown to have reactant conversion at low temperatures. The diffusion of reactants to the active metals in the CNTs can be improved by inducing defects in the tube walls through doping. CNT-supported catalysts have limited stability as reactant conversion is < 80% beyond a time of stream (TOS) of 15 h (at any temperature). MXenes can serve as catalyst supports or redox catalysts via oxidation-carburization cycles. The stability of MXenes in DRM is superior to commercial SiO2 and CNTs as they show reactant conversion >75% up to a TOS of 90 h. The tunable interlayer spacing between MXene sheets makes the intercalation of catalysts possible and can help impede sintering during DRM. The review also discusses issues around DRM upscaling and how nanomaterials will be relevant in addressing them.