Solution-Processable Small Molecules for High-Performance Organic Solar Cells with Rigidly Fluorinated 2,2 '-Bithiophene Central Cores
Solution-Processable Small Molecules for High-Performance Organic Solar Cells with Rigidly Fluorinated 2,2 '-Bithiophene Central Cores
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用于具有刚性氟化 2,2'-联噻吩中心核的高性能有机太阳能电池的可溶液加工小分子
DOI：
10.1021/acsami.6b01784
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发表时间：
2016
影响因子：
9.5
通讯作者：
Peng Qiang
中科院分区：
文献类型：
--
作者：
Wang Zhenguo;Li Zuojia;Liu Jiang;Mei Jun;Li Kai;Li Ying;Peng Qiang
含低聚噻吩主链的小分子是简单但有效的有机太阳能电池（OSC）给体材料。本论文以刚性的2，2 ′-联噻吩（BT）或氟化的2，2 ′-联噻吩（FBT）为中心单元，合成了两种新型的具有噻吩低聚物主链和3-乙基绕丹宁端基的小分子TTH-D3 TRh和TTF-D3 TRh。这两种分子都表现出良好的热稳定性以及强而宽的吸收。与TTH-D3 TRh相比，TTF-D3 TRh具有更低的HOMO能级、更好的分子堆积和更高的迁移率。制备常规的OSC以评估这两种分子的光伏性质。在没有额外的后处理的情况下，基于TTH-D3 TRh和TTF-D3 TRh的传统装置分别显示出5.00%和5.80%的高PCE。TTF-D3 TRh器件表现出更高的性能，这可以归因于改进的Voc0.92 V，Jsc10.04 mA cm-2，和FF 62.8%。使用倒置器件结构，基于TTH-D3 TRh和TTF-D3 TRh的OSC显示出分别为5.89%和7.14%的大幅升高的PCE。结果表明，结构简单的TTH-D3 TRh和TTF-D3 TR分子是获得高效OSC的潜在供体候选者。通过对低聚噻吩类小分子给体的结构设计和刚性设计，可以有效地开发出高效太阳能电池用的低聚噻吩类小分子给体。
Small molecules containing an oligothiophene backbone are simple but effective donor materials for organic solar cells (OSCs). In this work, we incorporated rigid 2,2′-bithiophene (BT) or fluorinated 2,2′-bithiophene (FBT) as the central unit and synthesized two novel small molecules (TTH-D3TRh and TTF-D3TRh) with an oligothiophene backbone and 3-ethylrhodanine end groups. Both molecules exhibit good thermal stability as well as strong and broad absorption. The fluorination of the BT central unit made TTF-D3TRh possess a relatively lower-lying HOMO energy level, better molecular stacking, and higher mobility in comparison with those of TTH-D3TRh. Conventional OSCs were fabricated to evaluate the photovoltaic property of these two molecules. Without extra post-treatments, the conventional devices based on TTH-D3TRh and TTF-D3TRh showed high PCEs of 5.00 and 5.80%, respectively. The TTF-D3TRh device exhibited a higher performance, which can be attributed to the improvedVocof 0.92 V,Jscof 10.04 mA cm–2, and FF of 62.8%. Using an inverted device structure, the OSCs based on TTH-D3TRh and TTF-D3TRh showed largely elevated PCEs of 5.89 and 7.14%, respectively. The results indicated that the structurally simple TTH-D3TRh and TTF-D3TR molecules are potential donor candidates for achieving highly efficient OSCs. The strategy of fluorination and rigidity designation is an effective approach to develop oligothiophene-based small molecular donors for highly efficient solar cell applications.