Phase mixing behaviour in evaporated thin films

The photovoltaic active layer of organic photovoltaics (OPVs) consists of a mixture of at least two kinds of energetically offset organic molecules, which gives rise to a complex microstructure across multiple length scales from Angstroms to micrometres. A common method to study the mixing of Polymer:Fullerene systems has been Small Angle Neutron Scattering (SANS), but the advantages of this technique have so far remained little exploited for vacuum evaporated small molecule-based systems, which are closest to commercial viability. We have recently successfully demonstrated the use of SANS to study the mixing behaviour of OPV evaporated thin films. We seek to expand upon our preliminary results to study the phase behaviour of vacuum evaporated thin films when the mixing ratio and substrate temperature is varied, and the effects on performance and characteristics of matching devices.

有机光伏（Organic Photovoltaics，OPVs）的光电活性层由至少两种能级偏移的有机分子混合构成，这使其微观结构在从埃至微米的多长度尺度范围内呈现出复杂特征。研究聚合物:富勒烯体系混合行为的常用方法为小角中子散射（Small Angle Neutron Scattering，SANS），但迄今为止，该技术的优势在最接近商业化可行性的真空蒸镀小分子基体系中尚未得到充分挖掘。我们团队近期已成功验证了利用小角中子散射研究OPV蒸镀薄膜混合行为的可行性。本数据集旨在拓展我们的初步研究成果，探究在改变混合比例与衬底温度时，真空蒸镀薄膜的相行为，以及其对匹配器件性能与特性的影响。