Enhancing the Efficiency of Polymer Solar Cells by Modifying Buffer Layer with N,N-Dimethylacetamide

Figure 5

The absorption spectrum of PEDOT:PSS/P3HT:PCBM thin film. A: only PEDOT:PSS solution on ITO at the speed of 3000 rpm. B: the PEDOT:PSS and DMAC mixed in a ratio of 4 : 1 (v/v) at the speed of 3000 rpm. C, D, and E: the PEDOT:PSS buffer layer modified by DMAC at speed of 1000, 3000, and 5000 rpm.