Sustainable System for Hydrogenation Exploiting Energy Derived from Solar Light
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Updated: Nov 19, 2025

Experimental Methods for Efficient Solar Hydrogen Production in Microgravity Environment
Published on: December 3, 2019
Naoki Ishida1, Yoshiki Kamae1, Keigo Ishizu1
1Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto 615-8510, Japan.
Abstract:
Herein described is a sustainable system for hydrogenation that uses solar light as the ultimate source of energy. The system consists of two steps. Solar energy is captured and chemically stored in the first step; exposure of a solution of azaxanthone in ethanol to solar light causes an energy storing dimerization of the ketone to produce a sterically strained 1,2-diol. In the second step, the chemical energy stored in the vicinal diol is released and used for hydrogenation; the diol offers hydrogen onto alkenes and splits back to azaxanthone, which is easily recovered and reused repeatedly for capturing solar energy.
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