Efficient solution-processed small molecule: Cadmium selenide quantum dot bulk heterojunction solar cells

We report bulk heterojunction solar cells based on blends of solution-processed small molecule [7,7′-(4,4-bis(2-ethylhexyl)-4H-silolo[3,2-b:4,5-b′]dithiophene-2,6-diyl) bis(6-fluoro-4-(5′-hexyl-[2,2′-bithiophen]-5yl)benzo[c] [1,2,5] thiadiazole)] p-DTS(FBTTh2)2: Cadmium Selenide (CdSe) (70:30, 60:40, 50:50, and 40:60) in the device configuration: Indium Tin Oxide /poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/p-DTS(FBTTh2)2: CdSe/Ca/Al. The optimized ratio of p-DTS(FBTTh2)2:CdSe::60:40 leads to a short circuit current density (Jsc) = 5.45 mA/cm2, open circuit voltage (Voc) = 0.727 V, and fill factor (FF) = 51%, and a power conversion efficiency = 2.02% at 100 mW/cm2 under AM1.5G illumination. The Jsc and FF are sensitive to the ratio of p-DTS(FBTTh2)2:CdSe, which is a crucial factor for the device performance