Exploring the Effect of Conduction Band Matching on Solar Cell Voltage and Efficiency for CdSe – Metal Oxide Quantum Dot Solar Cells

Liquid Junction quantum dot solar cells were constructed from three sizes of CdSe quantum dots on a variety of metal oxide nanoparticulate substrates. Metal oxides were chosen to closely match their conduction bands with the conduction bands of the CdSe. It was hypothesized that avoiding energy loss due to large differences between the CdSe and metal oxide conduction bands would increase the open circuit voltage and possibly the efficiency of these “band-matched” solar cells. We found that the opposite was true and that the improved electron kinetics due to larger differences in conduction band levels seems to have a larger influence on the efficiency of the cell.