ARC-PLASMA-SPRAYED RUTILE ANODES FOR PHOTOELECTROLYSIS OF WATER

Rutile (TiO2) anodes prepared by arc-plasma spraying of raw rutile powder containing Si, Fe, Cr, Ni, and Mn impurities performed similarly in photoelectrolysis experiments to polycrystalline TiO2 electrodes made by chemical vapor deposition and by oxidation of metal foils. The impure arc-plasma-sprayed anodes showed photoresponse characteristics and flatband potential comparable to that of single crystal TiO-2, but the breakdown voltage was lower. The low breakdown voltage was attributed to electron tunneling through the thin depletion region of the strongly reduced TiO2 via grain boundaries containing impurity atoms and second phases. © 1979, The Electrochemical Society, Inc. All rights reserved.