摘要
Geometrical light trapping is a simple and prom- ising strategy to largely improve the optical absorption and efficiency of solar cell. Nonetheless, implementation of geo- metrical light trapping in organic photovoltaic is challenging due to the fact that uniform organic active layer can rarely be achieved on textured substrate. In this work, squarely ordered nanobowl array （SONA） is reported for the first time and [6,6]- phenyl-C6rbutyric acid methyl ester （PCBM）：poly（3-hexyl- thiophene） （P3HT）-based organic photovoltaic （OPV） device on SONA demonstrated over 28 % enhancement in power conversion efficiency over the planar counterpart. Interestingly, finite-difference time-domain （FDTD） optical simulation revealed that the superior light trapping by SONA originated from optical concentrator effect by nanobowl. Furthermore, aiming at low-cost, solution processible, and resource sus- tainable flexible solar cells, we employed Ag nanowires for the top transparent conducting electrode. This work not only revealed the in-depth understanding of light trapping by nanobowl optical concentrator, but also demonstrated the fea- sibility of implementing geometrical light trapping in OPV.
几何陷光是一种简单且极具希望成为大幅度提高太阳能电池的光吸收和效率的方案.然而,由于很难在粗糙的衬底上均匀涂敷有机吸光层,在有机光伏电池中实现几何陷光非常具有挑战性.本文报道了一种基于方形排序的纳米碗阵列(SONA)的PCBM:P3HT有机光伏电池.这种电池比相应的基于平面阵列的电池在光电能量转换效率方面提高了28%以上.时域有限差分法(FDTD)光学模拟显示,SONA优越的陷光性能源自纳米碗阵列的聚光效应.此外,为了实现低成本、可湿法加工、资源可持续性的柔性太阳能电池,本文采用银纳米线作为顶部透明电极.本研究不仅深入展示了基于纳米碗聚光器的高效陷光效应,还解释了在有机光伏电池中实现几何陷光的可行性.
基金
supported by the HK-RGCGeneral Research Funds(HKUST 605710,604809,612111,612113)
partially supported by ITS/117/13 from Hong Kong Innovation Technology Commission
