TEMPERATURE EFFECTS IN PHOTOELECTROCHEMICAL CELLS

The performance of photoelectrochemical cells made of an n-type TiO 2 photoanode and the O2/OH- redox electrolyte system have been studied at different temperatures. It has been found that when only the photoanode compartment is heated, the open-circuit voltage decreases (∼2.0 mV K-1) and the short-circuit current increases (∼0.8 mA m-2 K-1); however, the power output shows a small increase and a fall thereafter. The behavior is similar to that of Schottky-barrier solar cells. When both of the electrode compartments are heated, the power output increases with increasing temperature (∼0.4 mW m-2 K-1) and this can be attributed to the enhancement of the rate of the electrochemical reaction at the counterelectrode.