Enhancement of the power conversion efficiency for organic photovoltaic devices due to an embedded rugged nanostructural layer

► OPV cells utilizing a nanostructural layer were fabricated using a mixed solution. ► The interface region of nanostuctural layer was larger than that of planar layer. ► The charge separation efficiency was enhanced due to the increased interface. ► The PCE values of the OPV cells with planar and nanostructural layers were 0.8% and 1.04%, respectively. ► The PCE and the Jsc values were significantly improved.