Modified catalysts and process for the solar reduction of water

摘要

A solar reaction system which produces hydrogen by reduction of hydronium ions using methylviologen or a related compound as an electron-transfer agent and a platinum electron-transfer catalyst, wherein the catalyst is modified with a water-soluble divalent sulphur compound, or a sulphur compound in which the sulphur is reducible to the divalent state, in an amount sufficient to inhibit hydrogenation side-reactions during the solar reduction process but not sufficient to significantly suppress the reduction of hydronium ion to hydrogen by the electron-transfer agent.