School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore.
Nanotechnology. 2012 Aug 10;23(31):315401. doi: 10.1088/0957-4484/23/31/315401. Epub 2012 Jul 13.
We report for the first time the fabrication and characterization of organic-inorganic bulk heterojunction (BHJ) hybrid solar cells made of poly[N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT) and pyridine-capped CdSe nanorods. By optimizing both CdSe loading and active layer film thickness, the power conversion efficiencies (PCEs) of PCDTBT:CdSe hybrid solar cells were able to reach 2%, with PCDTBT:CdSe devices displaying an open-circuit voltage (V(OC )) that is 35% higher than P3HT:CdSe devices due to the deeper HOMO level of PCDTBT polymer. The performance of PCDTBT:CdSe devices is limited by its morphology and also its lower LUMO energy offset compared to P3HT:CdSe devices. Hence, the performance of PCDTBT:CdSe solar cells could be further improved by modifying the morphology of the films and also by including an interlayer to generate a built-in voltage to encourage exciton dissociation. Our results suggest that PCDTBT could be a viable alternative to P3HT as an electron donor in hybrid BHJ solar cells for high photovoltage application.
我们首次报道了由聚[N-9″-庚基-2,7-咔唑-alt-5,5-(4',7'-二噻吩-2',1',3-苯并噻二唑)] (PCDTBT) 和吡啶封端的 CdSe 纳米棒制成的有机-无机体异质结 (BHJ) 混合太阳能电池的制造和特性。通过优化 CdSe 负载和活性层膜厚度，PCDTBT:CdSe 混合太阳能电池的功率转换效率 (PCE) 能够达到 2%，PCDTBT:CdSe 器件的开路电压 (V(OC)) 比 P3HT:CdSe 器件高 35%，这是由于 PCDTBT 聚合物具有更深的 HOMO 能级。PCDTBT:CdSe 器件的性能受到其形态和与 P3HT:CdSe 器件相比更低的 LUMO 能量偏移的限制。因此，通过修饰薄膜的形态以及通过包括一个内置电压层来促进激子解离，可以进一步提高 PCDTBT:CdSe 太阳能电池的性能。我们的结果表明，PCDTBT 可以作为 P3HT 的替代物，作为用于高光电压应用的混合 BHJ 太阳能电池中的电子给体。
