A comparative study of the effects of Ag2S films prepared by MPD andHRTD methods on the performance of polymer solar cells
Yong Zhai, Fumin Lia, Lanyun Linga, Chong Chen∗
In this work, the Ag2S nanocrystalline thin films are deposited on ITO glass via molecular pre-cursor decomposition (MPD) method and newly developed HRTD method for organic solar cells(ITO/Ag2S/P3HT:PCBM/MoO3/Au) as an electron selective layer and a light absorption material. The sur-face morphology, structure characterization, and optical property of the Ag2S films prepared by thesetwo methods were compared and the effect of the prepared Ag2S film on the device performance isinvestigated. It is found that the Ag2S films prepared by HRTD method have lower roughness and betteruniformity than the corresponding films prepared by the MPD method. In addition, a more effective andrapid transporting ability for the electrons and holes in the ITO/Ag2S(HRTD, n)/P3HT:PCBM/MoO3/Aucells is found, which reduces the charge recombination, and thus, improves the device performance. Thehighest efficiency of 3.21% achieved for the ITO/Ag2S(HRTD, 50)/P3HT:PCBM/MoO3/Au cell is 93% higherthan that of the ITO/Ag2S(MPD, 2)/P3HT:PCBM/MoO3/Au cell.