Aïssa Brahim, Nedil Mourad, Kroeger Jens, Ali Adnan, Isaifan Rima J, Essehli Rachid, Mahmoud Khaled A
MPB Technologies Inc., Department of Smart Materials and Sensors for Space Missions, 151 Hymus Boulv. Pointe Claire, Canada. Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar. Division of Sustainable Development, Hamad Bin Khalifa University, Qatar Foundation, PO Box 5825, Doha, Qatar.
Nanotechnology. 2018 Mar 9;29(10):105405. doi: 10.1088/1361-6528/aaa62d.
Hybrid organic photovoltaic (OPV) cells based on conjugated polymer photoactive materials are promising candidates for flexible, high-performance and low-cost energy sources owing to their inexpensive materials, cost-effective processing and ease of fabrication by simple solution processes. However, the modest PV performance obtained to date-in particular the low power conversion efficiency (PCE)-has impeded the large scale deployment of OPV cells. The low PCE in OPV solar cells is mainly attributed to the low carrier mobility, which is closely correlated to the transport diffusion length of the charge carriers within the photoactive layers. The 2D graphene material could be an excellent candidate for assisting charge transport improvement in the active layer of OPV cells, due to its huge carrier mobility, thermal and chemical stability, and its compatibility with the solution process. In this work, we report on the improvement of the optoelectronic properties and photovoltaic performance of graphene nanoplatelet (GNP)-doped P3HT:PCBM photoactive blended layers, integrated into a bulk heterojunction (BHJ) organic-photovoltaic-based device, using PEDOT:PSS on an ITO/glass substrate. First, the light absorption capacity was observed to increase with respect to the GNP content, while the photoluminescence showed clear quenching, indicating electron transfer between the graphene sheets and the polymeric matrix. Then, the incorporation of GNP into the BHJ active layer resulted in enhanced PV performance with respect to the reference cell, and the best PV performance was obtained with 3 wt.% of GNP loading, with an open-circuit voltage of 1.24 V, a short-circuit current density value of 6.18 mA cm, a fill factor of 47.12%, and a power conversion efficiency of about 3.61%. We believe that the obtained results contribute to the development of organic photovoltaic devices and to the understanding of the impact of sp-bonded carbon therein.
基于共轭聚合物光活性材料的混合有机光伏(OPV)电池因其材料成本低、加工成本效益高且易于通过简单的溶液工艺制造,有望成为灵活、高性能和低成本能源的候选者。然而,迄今为止获得的适度光伏性能——特别是低功率转换效率(PCE)——阻碍了OPV电池的大规模部署。OPV太阳能电池中的低PCE主要归因于低载流子迁移率,这与光活性层内电荷载流子的传输扩散长度密切相关。二维石墨烯材料因其巨大的载流子迁移率、热稳定性和化学稳定性以及与溶液工艺的兼容性,可能是协助改善OPV电池活性层中电荷传输的极佳候选材料。在这项工作中,我们报告了使用ITO/玻璃基板上的PEDOT:PSS,将石墨烯纳米片(GNP)掺杂的P3HT:PCBM光活性混合层集成到体异质结(BHJ)有机光伏器件中后,其光电性能和光伏性能的改善情况。首先,观察到光吸收能力随GNP含量增加而增强,而光致发光显示出明显的猝灭,表明石墨烯片与聚合物基体之间发生了电子转移。然后,将GNP掺入BHJ活性层导致相对于参考电池而言光伏性能得到增强,在GNP负载量为3 wt.%时获得了最佳光伏性能,开路电压为1.24 V,短路电流密度值为6.18 mA cm,填充因子为47.12%,功率转换效率约为3.61%。我们相信,所获得的结果有助于有机光伏器件的发展,并有助于理解其中sp键合碳的影响。