Nanostructured hematite for photoelectrochemical generation of hydrogen

With the advent of nanotechnology there has been a resurge of interest in αα-Fe2O3, as suitable candidate for photoelectrochemical (PEC) splitting of water to generate hydrogen. This paper describes the enhanced PEC behaviour of nanostructured αα-Fe2O3 thin films modified by various techniques. Nanostructured thin film/pellets of αα-Fe2O3 prepared by various techniques and various dopants were investigated for their photoelectrochemical response. Thin films prepared by spray pyrolysis having particle size of 20–30 nm exhibited better photoresponse as compared to the films prepared by sol–gel methods, which further improved on doping with Zn. These films were further modified by (i) depositing Zn dots on the surface of αα-Fe2O3 films using thermal evaporation method and (ii) irradiating it with 170 MeV Au13+Au13+ ions. When used as electrode in photoelectrochemical cell, a significant increase in the photoresponse of these modified films were observed, details of which are discussed.