Electret field enhanced organic photovoltaic cells

Organic photovoltaic devices (OPVs) are realizing power conversion efficiencies that are of interest for commercial production. However, cell efficiencies are poor to modest when compared to their more traditional silicon and other inorganic based counterparts. Apart from material breakthroughs, there is immense need to therefore engineer novel approaches to improve OPV cell performance. In this work, we have demonstrated feasibility of “Electretic” organic solar cells with improved efficiency based on incorporating functional electret materials into optimized organic photovoltaic cells. Dielectric Materials with the capability of storing electrical excess charges and therefore generating an electric field to adjacent electrodes or semiconductors are known as electrets [1]. The most significant feature of electrets is that they can be charged, discharged and recharged in a very controlled manner after preparation of the whole device in which they are used. In this proof of concept work, we have demonstrated dramatic improvement achieved in the current-voltage characteristic of conventional, simple OPV cells by simulating the electric field effects of an embedded electret layer by external high voltage DC bias levels. The concept will be revolutionary in enabling organic solar cells to break through the efficiency/ cost barrier to become more broadly, more quickly adopted.