Enhancing the efficiency of inverted organic solar cells by using the exciton blocking layers

In this study, inverted organic solar cells (IOSCs) have been fabricated and characterized. Device´s structure consists of the blend of poly(3-hexythiophene)(P3HT) and [6,6]-phenyl C61-butyric acid methyl ester(PCBM) as an active layer and a solution process of ZnO and V₂O₅ as a hole blocking layer (HBL) and electron blocking layer (EBL), respectively. The blocking layer possesses high charge mobility and wide band gap. The wide band gap can effectively suppress the diffusion of electron and hole separating from exciton to the electrodes, reducing the combined effect. Experimental results reveal that ZnO annealed in high temperature to procure nano-ridge can effectively enhance electrons to transport from active layer to the cathode.