Zillner, E.; Dittrich, Th.: Surface photovoltage within a monolayer of CdSe quantum dots. Physica Status Solidi - Rapid Research Letters 5 (2011), p. 256-258
10.1002/pssr.201105174
Abstract:
Layers of pyridine terminated CdSe quantum dots (QDs) with thicknesses from a monolayer (ML) to 80 nm were deposited on ITO substrates by dip coating. Transient surface photovoltage measurements showed dominant charge separation within the first ML of QDs at short times and an increasing influence of layer thickness at long times. Auger recombination limited the maximum of separated charge carriers to about 1 × 1012 cm-2. Separation of photo-generated electron-hole pairs within a ML of CdSe-QDs. Electrons were either trapped on ITO surface states or separated due to a built-in electrical field created by a transferred electron from the ITO to a trap state at the QD.