Contact-free photovoltage measurements of photoabsorbers using a Kelvin probe

A contact free method, aimed at measuring the photovoltage that can be generated by an absorber, upon illumination, was presented. The measurement, based on Kelvin's capacitor method measures the contact potential difference built up between two sufficiently conducting materials of different electrically connected work functions. It was shown that the photovoltage of an absorber, introduced into the Kelvin capacitor, could be measured accurately, even if it was not in electrical contact to any of the capacitor plate. The approach was shown to enable the measurement of photovoltage of complete solar cells and also its single components.