Conversion efficiency improvement mechanisms of polymer solar cells by balance electron–hole mobility using blended P3HT:PCBM:pentacene active layer

•The pentacene was used to balance hole–electron mobility on the active layer.•Using SCLC model analyze the hole-only devices and the electron-only devices.•The P3HT:PCBM:pentacene active layer exhibited balance hole–electron mobility.•The power conversion efficiency was improved about 27.5%.

To improve the power conversion efficiency of polymer solar cells, the blended P3HT:PCBM:pentacene active layer was used to balance hole–electron mobility and roughen surface. Using space-charged-limited current model to analyze the hole-only devices and the electron-only devices, the P3HT:PCBM:pentacene (weight ratio = 1:0.8:0.09) active layer exhibited balance hole–electron mobility. Compared with the power conversion efficiency of 3.46% of the conventional polymer solar cells using P3HT:PCBM (1:0.8) active layer, the power conversion efficiency of 4.42% was obtained. In other words, the power conversion efficiency was improved about 27.5%.

Graphical abstractTo improve the power conversion efficiency of polymer solar cells, the blended P3HT:PCBM:pentacene active layer was used to balance hole–electron mobility and roughen surface. Using space-charged-limited current model to analyze the hole-only devices and the electron-only devices, the P3HT:PCBM:pentacene (weight ratio = 1:0.8:0.09) active layer exhibited balance hole–electron mobility.Figure optionsDownload full-size imageDownload as PowerPoint slide