School of Semiconductor and Chemical Engineering, Chonbuk National University , 567 Baekje-daero, Jeonju, 54896, Republic of Korea.
Division of Advanced Materials, Korea Research Institute of Chemical Technology (KRICT) , 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea.
ACS Appl Mater Interfaces. 2017 Feb 1;9(4):3831-3841. doi: 10.1021/acsami.6b10843. Epub 2017 Jan 17.
1-D ZnO represents a fascinating class of nanostructures that are significant to optoelectronics. In this work, we investigated the use of an eco-friendly, metal free in situ doping through a pure thiophene-sulfur (S) on low temperature processed (<95 °C) and annealed (<170 °C), planar 1-D ZnO nanorods (ZnRs) spin-coated as a hole-blocking and electron transporting layer (ETL) for inverted organic solar cells (iOSCs). The TEM, HRTEM, XPS, FT-IR, EDS and Raman studies clearly reveal that the thiophene-S (Thi-S) atom is incorporated on planar ZnRs. The investigations in electrical properties suggest the enhancement in conductivity after Thi-S doping on 1-D ZnRs. The iOSCs of poly(3-hexylthiophene-2,5-diyl) and phenyl-C-butyric acid methyl ester (P3HT: PCBM) photoactive layer containing thiophene-S doped planar ZnRs (Thi-S-PZnRs) as ETL exhibits power conversion efficiency (PCE) of 3.68% under simulated AM 1.5 G, 100 mW cm illumination. The ∼47% enhancement in PCE compared with pristine planar ZnRs (PCE = 2.38%) ETL is attributed to a combination of desirable energy level alignment, morphological modification, increased conductivity and doping effect. The universality of Thi-S-PZnRs ETL is demonstrated by the highest PCE of 8.15% in contrast to 6.50% exhibited by the iOSCs of ZnRs ETL for the photoactive layer comprising of poly[4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)benzo[1,2-b;4,5-b]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)]: phenyl-C71-butyric acid methyl ester (PTB7-Th: PCBM). This enhancement in PCE is observed to be driven mainly through improved photovoltaic parameters like fill factor (ff) as well as photocurrent density (J), which are assigned to increased conductivity, exciton dissociation, and effective charge extraction, while; better ohmic contact, reduced charge recombination, and low leakage current density resulted in increased V.
1-D ZnO 代表了一类引人入胜的纳米结构，它们在光电子学中具有重要意义。在这项工作中，我们研究了在低温处理（<95°C）和退火（<170°C）条件下，通过纯噻吩-硫（S）进行环保、无金属原位掺杂的方法，将平面 1-D ZnO 纳米棒（ZnRs）旋涂为空穴阻挡和电子传输层（ETL），用于倒置有机太阳能电池（iOSCs）。TEM、HRTEM、XPS、FT-IR、EDS 和 Raman 研究清楚地表明，噻吩-S（Thi-S）原子被掺入平面 ZnRs 中。电性能研究表明，在 1-D ZnRs 上进行 Thi-S 掺杂后，导电性得到增强。包含噻吩-S 掺杂平面 ZnRs（Thi-S-PZnRs）作为 ETL 的聚（3-己基噻吩-2,5-二基）和苯基-C-丁酸甲酯（P3HT: PCBM）光活性层的 iOSCs 在模拟 AM 1.5 G、100 mW cm 光照下的功率转换效率（PCE）为 3.68%。与原始平面 ZnRs（PCE = 2.38%）ETL 相比，PCE 提高了约 47%，这归因于理想的能级对准、形貌修饰、导电性提高和掺杂效应的综合作用。噻吩-S-PZnRs ETL 的普遍性通过与 ZnRs ETL 的 iOSCs 相比，对于包含聚[4,8-双（5-（2-乙基己基）噻吩-2-基）苯并[1,2-b;4,5-b]二噻吩-2,6-二基）-交替-（4-（2-乙基己基）-3-氟噻吩[3,4-b]噻吩-2-基）-2-羧酸酯-2,6-二基]：苯基-C71-丁酸甲酯（PTB7-Th：PCBM）光活性层的 iOSCs 相比，最高 PCE 为 8.15%，而达到 6.50%。这种 PCE 的提高主要归因于光伏参数的改善，如填充因子（ff）和光电流密度（J），这归因于导电性的提高、激子解离和有效电荷提取，而欧姆接触的改善、电荷复合的减少和漏电流密度的降低导致 V 的增加。
