Characterization of a composite film prepared by deposition of TiO2 on porous Si

Ti[O.sub.2] thin films were prepared on electrochemically etched porous Si by anodic oxidative hydrolysis of Ti[Cl.sub.3] for the purpose of solar cell application. We compared electrochemical and photoelectrochemical properties of the Ti[O.sub.2]-deposited porous Si electrodes (Ti[O.sub.2]/porous Si) with those of a porous Si electrode. The Ti[O.sub.2]/porous Si showed prolonged stability of photoluminescence and enhancements of photovoltage and photocurrent by 0.13 V and 67% increase, respectively, in comparison with porous Si due to the reduction of surface traps for charge carriers in the presence of Ti[O.sub.2] thin layer. [Li.sup.+] and [Na.sup.+] ions exhibited intercalation and deintercalation through the electrodeposited Ti[O.sub.2] film.