In this study, we investigate a carboxyl indoline dye named D205 with deep highest occupied molecular orbital energy level of −5.4 eV as donor material together with [6,6]-phenyl C₇₁ butyric acid methyl ester (PC₇₀BM) as acceptor material in solution-processed bulk heterojunction solar cells. We employ chloroform (CF) and chlorobenzene (CB) as different solvents to investigate the influence of which on the active layer phase separation. The morphologies of D205:PC₇₀BM with CB as solvent seem to be stable as the ratio of PC₇₀BM increasing while it shows obvious change when processed by CF. The root-mean-square (RMS) values processed in CB change from 1.2 nm (D205:PC₇₀BM = 1:2) to 0.8 nm (D205:PC₇₀BM = 1:19). While the RMS values processed in CF change from 1.1 nm (D205:PC₇₀BM = 1:2) to 13 nm (D205:PC₇₀BM = 1:19). This may originate from that the rapid volatilization of CF solvent, leading to the aggregation behavior of the blending layer especially the aggregates of PC₇₀BM. A proper RMS value leads to a better phase separation and thus can prompt balanced holes and electrons transportation. This can eventually benefit the short-circuit current. By regulating the ratio of D205:PC₇₀BM as 1:4 in CB, an optimized power conversion efficiency(PCE) of 3.0% was reached after device annealing at 90 °C for 1 min under standard AM 1.5100 mW/cm² sunlight.

在这项研究中，我们研究了一种名为D205的羧基吲哚染料，其供体材料的分子轨道能级最高为-5.4 eV，供体材料为[6,6]-苯基C ₇₁丁酸甲酯（PC ₇₀ BM）。在溶液处理的体异质结太阳能电池中。我们使用氯仿（CF）和氯苯（CB）作为不同的溶剂来研究其对活性层相分离的影响。D205的形态：PC ₇₀ BM与CB作为溶剂似乎是稳定的，因为PC的比率₇₀ BM增加而它显示了明显的变化时，由处理CF. 在CB中处理的均方根（RMS）值从1.2 nm（D205：PC ₇₀ BM = 1：2）变为0.8 nm（D205：PC₇₀ BM = 1:19）。而在CF中处理的RMS值从1.1 nm（D205：PC ₇₀ BM = 1：2）变为13 nm（D205：PC ₇₀ BM = 1:19）。这可能源于CF溶剂的快速挥发，导致共混层的聚集行为，尤其是PC ₇₀ BM的聚集体。适当的RMS值会导致更好的相分离，从而促进平衡的空穴和电子传输。这最终可以使短路电流受益。通过将D205：PC ₇₀ BM在CB中的比例调节为1：4，在标准AM 1.5100 mW / cm ²阳光下，器件在90°C退火1分钟后，可实现3.0％的优化功率转换效率（PCE）。