High efficiency organic/silicon hybrid solar cells with doping-free selective emitter structure induced by a WO3 thin interlayer

Organic/silicon hybrid solar cell has recently received intensive interest due to its simple and low-cost fabrication process, which could be potentially used in photovoltaics. However, the efficiency of organic/silicon solar cell needs further improvement. Here, we have introduced a WO3 thin layer between the Ag front electrodes and poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate)(PEDOT:PSS) film in the PEDOT:PSS/silicon solar cell to form a doping-free selective emitter (SE) structure. The carrier recombination is suppressed at the interface of silicon and electrodes, and meanwhile, the contact resistance between the Ag electrodes and PEDOT:PSS film is largely reduced. Therefore, the open-circuit voltage and fill factor of solar cell is significantly improved. As a result, the solar cell with a SE structure displays the power conversion efficiency (PCE) of 11.65%, which is much higher than the one without a WO3 thin layer. These results pave a new way for the fabrication of high efficiency organic/silicon hybrid solar cells. (C) 2015 Elsevier Ltd. All rights reserved.