Tungsten trioxide as a photoanode for a photoelectrochemical cell (PEC)

THE PEC¹ has acquired popularity among researchers in the past years, mainly because of its possible use in solar energy conversion ^2,3. The major problem at present is to find a semiconductor electrode with an optical band gap (written as just band gap below) small enough to allow it to absorb a reasonably large portion of the solar spectrum, and at the same time being stable against photocorrosion. We here report that WO ₃ meets these criteria although it is not very efficient at solar wavelengths.