Obviously, as the concentration of CIGS NCs increases, the Jsc linearly increases due to the increasing of interfaces between P3HT and CIGS NCs, whereas the Voc
decreases due to the decreasing of the shunt resistance. Consequently, the best photovoltaic devices with the optimal ratio (P3HT/CIGS NCs) of 60 wt.% can be found, with which the highest Jsc and Voc of approximately 59 μA/cm2 and approximately 0.76 V were measured, yielding the PCE (η) of approximately 0.011% with the FF of 0.25. Figure 3 I-V characteristics and Jsc, Voc, FF, and PCE of pristine and composition mixture of P3HT/CIGS NCs. (a) I-V characteristics with the P3HT/CIGS NC composite layer at different mixing ratios and (b,c) Jsc, Voc, FF, and PCE as the function of the CIGS NCs concentrations. Table 1 Device measurement of P3HT/CIGS NC hybrid solar
#selleck compound randurls[1|1|,|CHEM1|]# cells under AM 1.5 at different mixing ratios CIGS NCs (wt.%) Jsc (μA/cm2) Voc (mV) FF (%) η (%) 0 27 1,100 23.9 0.0071 20 32 1,060 25.9 0.0088 40 41 940 22.2 0.0086 60 59 760 25.1 0.0110 80 53 600 27.6 0.0080 Solvent effects on CIGS NCs/P3HT hybrid solar cells By controlling the morphology of the active layer, the performance of the hybrid solar cell can be enhanced owing to the efficient charge transfer, transport, and collection strongly rely on the separated phases and morphologies in the polymer/NC layer [19]. The nanoscale
morphology of an active layer mainly depends on the film preparation, including the use of AZD1480 ic50 different solvents, mixture of multiple solvents, control of solvent evaporation rate, and drying time oxyclozanide [20]. Here, we investigated the morphology control in the P3HT/CIGS NC layer at different solvents, including chloroform, chlorobenzene, and dichlorobenzene as shown in Figure 4a,b,c, respectively. Comparing the atomic force microscope (AFM) images of chloroform, chlorobenzene, and dichlorobenzene-cast films, the dichlorobenzene-cast film achieves the smallest surface roughness of approximately 10 nm (approximately 25 to 30 nm for chloroform, approximately 40 to 50 nm for chlorobenzene). In order to compare the impact of the different morphologies and its corresponding device performance, all devices were fabricated in unity process except for the option of solvent adopted for spin coating of the active layer. Figure 4e shows a plot of the current density versus voltage for the three devices. Obviously, the Voc decreases from chloroform (1,060 mV), chlorobenzene (920 mV) to dichlorobenzene (760 mV) while the Jsc increases from chloroform (32 μA/cm2), chlorobenzene (40 μA/cm2) to dichlorobenzene (59 μA/cm2). As a result, the dichlorobenzene-based device exhibited the best PCE (0.011%), indicating high converting rate of photons to electrons.