Photoassisted electrolysis of water by visible irradiation of a p-type gallium phosphide electrode

Photoelectrolytic decomposition of water with visible irradiation is demonstrated in a cell made of p-type gallium phosphide as the cathode and platinum as the anode. A maximum energy conversion efficiency of 0.1 percent is achieved with an external bias of 1.3 volts. The stability of the electrode is demonstrated, and the results are discussed in terms of a composite energy diagram.