本研究是針對溶液加工法(solvent engineering)製備鈣鈦礦主動層做進一步的變化，溶液加工法已經是很成熟的製成，一般所使用的溶液皆為無極性溶液如甲苯、氯苯以及鄰-二氯苯，而使用甲苯做為溶液加工法所形成的薄膜會先經過鈣鈦礦中間相(MAI-PbI2-DMSO)再藉由退火形成鈣鈦礦相，而氯苯及鄰-二氯苯則是直接形成鈣鈦礦相，又由於兩者揮發速度造成結晶尺寸不同，使得效率特性有所差異。此研究藉由混合會造成不同結晶的溶液後做溶液加工法並且觀察其中的變化，以10、30、50、70、90 vol%之甲苯分別與氯苯以及鄰-二氯苯做混合，使得混合溶液加工法後中間相以及鈣鈦礦相有最佳的比例，藉此觀察最後製備出的元件特性。
元件光電特性結果顯示，使用混合溶液加工法所製備的元件，填充因子以及電流密度皆與原先單溶液有所提升，其中又以70、90 vol%的甲苯與氯苯混合有明顯的不同，填充因子從原先0.69提升至0.73，影響填充因子其中的因素串聯電阻也有明顯下降，而電流密度也從原先15.65 mA cm^(-2)提升至17.02 mA cm^(-2)甚至可達到18.5 mA cm^(-2)，而與鄰-二氯苯混合後，也可以提升電流密度至16.86 mA cm^(-2)，並使其填充因子從0.68提升至0.73，以結果呈現證明藉由混和不同特性的溶液可以改善元件特性進而增加效率。

The objective of this paper is to improve cell performance of Perovskite solar cells by using mixed non-solvents dripping on the active layer. Three different non-solvents, i.e., toluene, chlorobenzene or dichlorobenzene were commonly used for solvent engineering. However, toluene can remove excess solvents and quickly form intermediate phase. On the other hand, the use of dichlorobenzene or chlorobenzene to wash the film to make the phase transformation can skip formation of large-scale Perovskite-DMSO intermediate and directly form Perovskite crystallites. The chlorobenzene has faster evaporation rate as compared with dichlorobenzene, However rapid crystallization process increases crytal growth rate, which leads to formation of big size crytals. In the current work, different proportions of toluene mixed with chlorobenzene or dichlorobenzene are used to wash the film. By this way we can observe the intermediate phase mix Perovskite phase and improve cells properties.
The photovoltaic properties of the devices show that the efficiency of PSCs fabricated by mixed solvents engineering can improve fill factor and current density compare with single solvent, especially 70 and 90 vol% toluene mixed with chlorobenzene has obvious improve. Fill factor promots from 0.69 to 0.73, and can reduce series resistance, current density increase from 15.65 mA cm^(-2) to 17.02 mA cm^(-2), final efficiency can be improve by mixed solvents engineering.

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