Table 1: Root means square, peak-valley value of active layers, and power conversion efficiency of photovoltaic devices fabricated using the active layers with and without TiO layer.

Method of preparation Active layer RMS (nm) Peak-valley value (nm) PCE (%) Spray coating Without TiO 0.56 4.32 1.76 With TiO 0.47 5.47 4.01 Spin coating With TiO 0.69 7.08 3.56