Zhang Wenqing, Sun Chenkai, Angunawela Indunil, Meng Lei, Qin Shucheng, Zhou Liuyang, Li Shaman, Zhuo Hongmei, Yang Guang, Zhang Zhi-Guo, Ade Harald, Li Yongfang
College of Chemistry, and Green Catalysis Center, Zhengzhou University, Zhengzhou, 450001, China.
Department of Physics and Organic and Carbon Electronics Laboratories (ORaCEL), North Carolina State University, Raleigh, NC, 27695, USA.
Adv Mater. 2022 May;34(20):e2108749. doi: 10.1002/adma.202108749. Epub 2022 Apr 17.
All-polymer solar cells (all-PSCs) have drawn growing attention and achieved tremendous progress recently, but their power conversion efficiency (PCE) still lags behind small-molecule-acceptor (SMA)-based PSCs due to the relative difficulty on morphology control of polymer photoactive blends. Here, low-cost PTQ10 is introduced as a second polymer donor (a third component) into the PM6:PY-IT blend to finely tune the energy-level matching and microscopic morphology of the polymer blend photoactive layer. The addition of PTQ10 decreases the π-π stacking distance, and increases the π-π stacking coherence length and the ordered face-on molecular packing orientation, which improves the charge separation and transport in the photoactive layer. Moreover, the deeper highest occupied molecular orbital energy level of the PTQ10 polymer donor than PM6 leads to higher open-circuit voltage of the ternary all-PSCs. As a result, a PCE of 16.52% is achieved for ternary all-PSCs, which is one of the highest PCEs for all-PSCs. In addition, the ternary devices exhibit a high tolerance of the photoactive layer thickness with high PCEs of 15.27% and 13.91% at photoactive layer thickness of ≈205 and ≈306 nm, respectively, which are the highest PCEs so far for all-PSCs with a thick photoactive layer.
全聚合物太阳能电池（全聚合物太阳能电池）最近受到了越来越多的关注并取得了巨大进展，但其功率转换效率（PCE）仍落后于基于小分子受体（SMA）的太阳能电池，这是由于聚合物光活性共混物的形态控制相对困难。在此，低成本的PTQ10被引入到PM6:PY-IT共混物中作为第二种聚合物供体（第三种组分），以精细调节聚合物共混物光活性层的能级匹配和微观形态。PTQ10的加入减小了π-π堆积距离，增加了π-π堆积相干长度和有序的面内分子堆积取向，从而改善了光活性层中的电荷分离和传输。此外，PTQ10聚合物供体的最高占据分子轨道能级比PM6更深，导致三元全聚合物太阳能电池的开路电压更高。结果，三元全聚合物太阳能电池实现了16.52%的功率转换效率，这是全聚合物太阳能电池的最高功率转换效率之一。此外，三元器件对光活性层厚度具有高耐受性，在光活性层厚度约为205和306nm时，功率转换效率分别高达15.27%和13.91%，这是迄今为止具有厚光活性层的全聚合物太阳能电池的最高功率转换效率。
