Bi2O3-WO3 compounds for photocatalytic applications by solid state and viscous processing

The semiconductor bandgaps of Bi2O3, WO3 and Bi2WO6 were found to be 0.2 eV, in agreement with previously reported results. Two sample preparation techniques have been considered-solid-state processing and viscous processing techniques. A custom-built, computerised micro-coextrusion system has been used to prepare intermediate compounds from the WO3-Bi2O3 binary oxide system and the design and optimisation of this technique are discussed.