Thin film Photoanode Materials

Chemical vapor deposition [37,38], and thermal or anodic oxidation of Ti substrates [39,40,41] have been used to prepare polycrystalline thin films of Ti02. For example, thin films of Ti02 prepared by anodic oxidation of Ti, followed by electrodeposition of In20s from 0.5 M 102(504)3 show enhanced optical absorption up to 500 nm [42] with the In203 modified electrode showing enhanced photocurrent and photovoltage partially due to the low electrical resistance (10 Q) and reduced overvoltage of the photoanode. 

1 General Synthesis Techniques of Semiconducting Thin-Fihns 

The photoelectrochemical behavior of a given photoanode is dependent on its method of synthesis. Various methods, some of which we now briefly consider, such as anodic oxidation, spray pyrolysis, reactive sputtering and vapor deposition are commonly employed to make polycrystalline thin films. 

Before anodizing a metal sample careful cleaning of the substrate is necessary for impurity removal. Several methods are available one 

LIki ruder) Fbotocurnil Flxt 6uad pureaiixl V vy SC l DunorUrn lt Brtnd pnp CeV) 

---

Nanocrystalline and Nanoporous Thin Film Materials as Photoanodes 219... 

---