Operando AP-XPS evaluation of semicondutor/liquid and associated systems

Through the use of tender X-rays from a synchrotron source, we evaluate the energetic relations of semiconductor/liq. junctions. A potentiostat maintains the working electrode, in a three electrode configuration, at an isopotential which can be varied throughout the potential range allowed by the electrolyte. We have evaluated the effects of metal deposition on the band energetics in the TiO_2/water system as well as providing a means to measure the defect state d. in a semiconductor in contact with a soln. Other expts. to investigate related systems will be discussed