Department of Industrial Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
Nanoscale Res Lett. 2014 Nov 18;9(1):620. doi: 10.1186/1556-276X-9-620. eCollection 2014.
Silicon nanowire arrays have been shown to demonstrate light trapping properties and promising potential for next-generation photovoltaics. In this paper, we show that the absorption enhancement in vertical nanowire arrays on a perfectly electric conductor can be further improved through tilting. Vertical nanowire arrays have a 66.2% improvement in ultimate efficiency over an ideal double-pass thin film of the equivalent amount of material. Tilted nanowire arrays, with the same amount of material, exhibit improved performance over vertical nanowire arrays across a broad range of tilt angles (from 38° to 72°). The optimum tilt of 53° has an improvement of 8.6% over that of vertical nanowire arrays and 80.4% over that of the ideal double-pass thin film. Tilted nanowire arrays exhibit improved absorption over the solar spectrum compared with vertical nanowires since the tilt allows for the excitation of additional modes besides the HE 1m modes that are excited at normal incidence. We also observed that tilted nanowire arrays have improved performance over vertical nanowire arrays for a large range of incidence angles (under about 60°).
硅纳米线阵列已经被证明具有光捕获特性，并且在下一代光伏技术中有很大的发展潜力。在本文中，我们展示了在理想的双层薄膜中，通过倾斜可以进一步提高垂直纳米线阵列在完美电导体上的吸收增强效果。垂直纳米线阵列在最终效率上比等效数量的材料的理想双层薄膜提高了 66.2%。与垂直纳米线阵列相比，在广泛的倾斜角度范围内（从 38°到 72°），具有相同材料的倾斜纳米线阵列表现出了更好的性能。最佳倾斜角度为 53°，与垂直纳米线阵列相比提高了 8.6%，与理想的双层薄膜相比提高了 80.4%。与垂直纳米线相比，倾斜纳米线阵列在太阳光谱中具有更好的吸收，因为倾斜可以激发除了在正常入射时激发的 HE1m 模式之外的其他模式。我们还观察到，倾斜纳米线阵列在较大的入射角范围内（约 60°以下）具有比垂直纳米线阵列更好的性能。
