How to make use of methanol in green catalytic hydrogen production?

Hydrogen production and storage as the core of novel hydrogen economy attract extensive attentions in both industry and academia. Methanol-involved hydrogen production has been considered as an alternative strategy towards conventional methane stream reforming owing to its milder reaction condition and lower carbon footprint. Currently, it mainly includes three branches: (1) thermocatalytic methanol reforming, (2) photocatalytic methanol reforming, and (3) photocatalytic water reduction using methanol as a sacrificial agent. These branches with many similarities, however, are relatively independent in their development stages and research focuses, which seriously restricted the fundamental understanding of using methanol as both hydrogen carrier and catalytic accelerant in hydrogen production reactions. We summarize latest research progresses by expounding their respective advantages, common and individual problems, as well as methods and experiences being developed. The role of methanol and its feasibility in photocatalytic hydrogen production were also discussed from both reaction mechanism and system cost-efficiency perspectives. Finally, frontiers of the three hydrogen production approaches are prospected, providing overall guidance for the potential application of economic and environmental sustainable methanol-mediated hydrogen energy.