An unprecedented photocatalytic architecture for benchmarking hydrogen production from methanol

Abstract

Abstract On-site hydrogen production from liquid organic hydrogen carriers e.g., methanol provides a disruptive strategy for the safe storage and transportation of hydrogen, thus promising to break the bottleneck of widely utilizing hydrogen as a global energy. Herein, we report an unprecedented photocatalytic architecture consisting of nickel-cobalt nanoclusters dispersed on gallium nitride nanowires for efficient and durable hydrogen production from methanol. By correlative microscopic and spectroscopic characterizations, as well as density functional theory calculations, it is revealed that NiCo nanoclusters work in synergy with GaN nanowires for hydrogen production from methanol with a significantly reduced reaction energy barrier. Together with the distinguished optoelectronic attributes, a benchmarking hydrogen evolution rate of 19.1 mol·gcat-1·h-1 with a prominent turnover frequency of 43460 mol H2 per mol NiCo per hour is achieved under concentrated light of 5 W·cm-2 without any extra energies. Remarkably, the synergy between Co and Ni, in combination with the unique surface of GaN, renders the architecture with outstanding resistance to sintering and coking. The architecture thereby exhibits a record-high turnover number of >16,310,000 mol hydrogen per mol NiCo over an ultra-long operation testing of 600 h. Outdoor testing validates the superior viability of the architecture for efficient and durable hydrogen evolution under natural concentrated sunlight. Overall, this work presents an unprecedented photocatalytic architecture for exceptional on-site hydrogen production from liquid organic hydrogen carriers e.g., CH3OH using virtually unlimited solar energy.