Analysis of the recombination mechanisms of a silicon solar cell with low bandgap-voltage offset was published. http://aip.scitation.org/doi/full/10.1063/1.4984071.
The mathematical dependence of bandgap-voltage offset on Auger and radiative recombination is derived. Open-circuit voltages over 760 mV were measured on 50-μm-thick structures, leading to bandgap-voltage offsets at open-circuit down to 0.35 V. We demonstrate the potential of thin silicon devices to reach high voltages, and bandgap-voltage offsets in line with the best reported for direct bandgap materials such as gallium indium phosphide and gallium arsenide.
Picture and legend: Intrinsic open-circuit voltage (black curve) and intrinsic bandgap offset open-circuit voltage (red curve) as a function of cell thickness, considering the Auger, the radiative recombination mechanisms as well as the Lambertian light-trapping limit. Recent experimental results of high VOC for silicon and the corresponding WOC are shown.