Photoreforming Light Alcohols for Value-Added Resources: A Mini Review

Hydrogen gas as a clean energy source, it is a promising alternative to fossil fuels. Therefore, people are actively seeking effective ways to produce hydrogen to cope with the imminent global energy shortage. However, the current production of hydrogen relies on the catalytic reforming of fossil fuels, inducing inevitable environmental pollution. Alternatively, photocatalysis for produce hydrogen gas from reforming alcohols is a promising approach. Especially, other value-added hydrocarbon products, such as acetone, acetaldehyde, acetic acid, etc., can also be produced during the photoreforming process of alcohols. Meanwhile, reducing the production of COx, making it an environmentally friendly conversion process. Outstandingly, TiO2 and its derivative are excellent photocatalysts. Among them, TiO2 cocatalyzed with noble metal can easily increase the H2 evolution rate to the mmol g−1 h−1 scale. Among the light alcohols isopropyl alcohol has fewer side reactions, methanol and ethanol have higher reaction rate, but they require to reduce the by-product COx. In this review, the recent developments in this field are summarized; various studies regarding H2 evolution rate, illumination condition, quantum efficiency, etc., are compared; and the development prospects of this field, with the hope of sparking widespread research interest, are proposed.