Solar-driven steam methane reforming (SMR) is a promising technology for hydrogen production. However, current solar thermochemical and photochemical reactions have different limitations. The former often requires high temperatures to achieve desired yield and neglects the strong activation ability of photons in short-wavelength spectrum, while the latter cannot use solar energy in the long-wavelength spectrum due to catalyst drawbacks, resulting in low solar energy utilization efficiency. To overcome these drawbacks, photo-thermal synergetic catalytic hydrogen production is proposed to achieve higher solar-to-hydrogen efficiency under relatively mild condition. In this work, the photo-thermal synergetic effect of solar hydrogen production from SMR using Co/Al2O3 catalyst is experimentally investigated. Results show the H2 yield by photo-thermochemical reaction (221.7 mmolÂ·h-1Â·g-1) can be increased by 42.8% at 650Â°C compared with that of the thermochemical reaction (155.2 mmolÂ·h-1Â·g-1), and the activation energy of the photo-thermochemical reaction is significantly reduced. The high activity is mainly attributed to photoactivation effect of light in photo-thermochemistry. These findings provide valuable guidance for hydrogen production from steam methane reforming using solar energy.
Keywords hydrogen production, solar fuel, photothermochemical reaction, steam methane reforming