DEVELOPMENT OF NB(X)TI(1-X)O(2-D) SEMICONDUCTING ELECTRODES FOR PHOTOELECTROLYSIS OF WATER

HARNESSING SOLAR ENERGY AS AN INEXHAUSTIBLE AND INEXPENSIVE SOURCE OF ENERGY HAS BEEN A GOAL OF MANKIND FOR CENTURIES. ONE OF THE MOST PROMISING SCHEMES NOW DEVISED TO HARNESS SOLAR ENERGY IS THE PHOTOELECTROLYTIC DECOMPOSITION OF WATERUSING SEMICONDUCTING ELECTRODES. ONE OF THE MAJOR PROBLEMS LIMITING INITIATION OF PRACTICAL PHOTOELECTROLYSIS IS ASSOCIATED WITH THE FACT THAT ONLY SEMICONDUCTING ELECTRODESWITH WIDE BAND GAPS OF 3 EV OR GREATER MAINTAIN CHEMICAL STABILITY DURING ILLUMINATION. IN THE PROPOSED PROGRAM OF RESEARCH CERAMATEC, INC. WILL ATTEMPT TO IDENTIFY CORROSION RESISTANT OXIDES WITH SMALLER BAND GAPS WHICH UTILIZE A LARGER FRACTION OF THE SOLAR SPECTRUM. SPECIFICALLY, IN THE PROPOSED PROGRAM THE TIO(2)-NBO(2) SYSTEM WHICH FORMS COMPLETE SOLID SOLUBILITY WILL BE INVESTIGATED. BY MANIPULATING THE RATIO OF NBO(2) TO TIO(2), IT IS EXPECTED THAT AN OPTIMUM SEMICONDUCTING MATERIAL CAN BE OBTAINED WHICH POSSESSES A BAND GAP BETWEEN 1.5 AND 2.5 EV, WHILE MAINTAINING AN ADEQUATE CORROSION RESISTANCE UNDER ILLUMINATION.