10.5% efficient polymer and amorphous silicon hybrid tandem photovoltaic cell

Thin-film solar cells made with amorphous silicon (a-Si) or organic semiconductors are considered as promising renewable energy sources due to their low manufacturing cost and light weight. However, the efficiency of single-junction a-Si or organic solar cells is typically <10%, insufficient for achieving grid parity. Here we demonstrate an efficient double-junction photovoltaic cell by employing an a-Si film as a front sub-cell and a low band gap polymer blend film as a back cell on planar glass substrates. Monolithic integration of 6.0% efficienct a-Si and 7.5% efficient polymer blend solar cells results in a power conversion efficiency of 10.5%. Such high-efficiency thin-film tandem cells can be achieved by optical management and interface engineering of fully optimized high-performance front and back cells without sacrificing photovoltaic performance in both cells.