A Direct Solar Photo‐Thermal Conversion of Methanol into Hydrogen

Abstract

Solar thermochemical hydrogen production has a great significance in the clean energy economy. Herein, for the first time, the direct reforming reaction of methanol into hydrogen using sunlight as the solar energy input in a homemade experiment setup is reported. Solar energy provides the thermal energy necessary for liquid evaporation and methanol reforming reaction simultaneously with the aid of the strong photo‐thermal conversion property of nano‐catalysts. The capillary force of sponge is utilized to promote the infiltration of nano‐catalysts with the water/methanol mixture. Experimental results demonstrate that the solar‐driven methanol reforming reaction takes place at a relatively low temperature (≈136 °C), and three factors, including the nano‐catalyst wetting time, the molar ratio of water/methanol, as well as the solar intensity, have noticeable influence on the reaction temperature, which determines the rate of hydrogen production. The maximum solar‐thermochemical conversion efficiency and solar energy utilization efficiency at optimum conditions reach 43.4% and 55.1%, respectively. The work will open a new approach for solar thermochemical energy conversion in the future.