Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano & Soft Materials (FUNSOM) , Soochow University , Suzhou 215123 , China.
ACS Appl Mater Interfaces. 2018 Apr 25;10(16):13767-13773. doi: 10.1021/acsami.8b02403. Epub 2018 Apr 12.
Silicon (Si)/organic heterojunction solar cells based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-type Si have attracted wide interests because they promise cost-effectiveness and high-efficiency. However, the limited conductivity of PEDOT:PSS leads to an inefficient hole transport efficiency for the heterojunction device. Therefore, a high dense top-contact metal grid electrode is required to assure the efficient charge collection efficiency. Unfortunately, the large metal grid coverage ratio electrode would lead to undesirable optical loss. Here, we develop a strategy to balance PEDOT:PSS conductivity and grid optical transmittance via a buried molybdenum oxide/silver grid electrode. In addition, the grid electrode coverage ratio is optimized to reduce its light shading effect. The buried electrode dramatically reduces the device series resistance, which leads to a higher fill factor (FF). With the optimized buried electrode, a record FF of 80% is achieved for flat Si/PEDOT:PSS heterojunction devices. With further enhancement adhesion between the PEDOT:PSS film and Si substrate by a chemical cross-linkable silance, a power conversion efficiency of 16.3% for organic/textured Si heterojunction devices is achieved. Our results provide a path to overcome the inferior organic semiconductor property to enhance the organic/Si heterojunction solar cell.
基于聚（3,4-亚乙基二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT:PSS）和 n 型硅的硅（Si）/有机异质结太阳能电池因其成本效益高和效率高而引起了广泛关注。然而，PEDOT:PSS 的有限导电性导致异质结器件的空穴传输效率低下。因此，需要高密的顶接触金属栅格电极来保证高效的电荷收集效率。不幸的是，大的金属网格覆盖率电极会导致不理想的光学损耗。在这里，我们通过埋层氧化钼/银栅格电极开发了一种平衡 PEDOT:PSS 电导率和栅格光透过率的策略。此外，优化了栅格电极的覆盖率，以减少其遮光效应。埋置电极大大降低了器件的串联电阻，从而提高了填充因子（FF）。通过优化的埋置电极，平面 Si/PEDOT:PSS 异质结器件的 FF 达到了 80%的纪录。通过进一步增强 PEDOT:PSS 薄膜与 Si 衬底之间的附着力，采用化学可交联硅烷，实现了有机/织构化 Si 异质结器件 16.3%的功率转换效率。我们的研究结果为克服有机半导体性能差的问题提供了一条途径，以提高有机/Si 异质结太阳能电池的性能。
