Qin Xuefei, Xia Zihuan, Wu Yonggang, Zhou Jian, Zhang Zongyi
Appl Opt. 2017 Mar 10;56(8):2307-2313. doi: 10.1364/AO.56.002307.
Silicon nanowire-based arrays have demonstrated superior light trapping properties and great potential for next-generation photovoltaics. In this paper, we propose a perpendicular elliptical nanocone (PENC) array solar cell, which introduces an asymmetry in the direction parallel to the array surface in addition to the asymmetry in the direction normal to the array surface, which has been implemented in the circular nanocone (CNC) array. The PENC array displays more and higher resonant absorption peaks in the long wavelength compared with the CNC array. The newly exhibiting absorption peaks are found to be derived from periodical Bloch modes by the band-folding of the PENC array and cavity modes introduced by the asymmetry of the elliptical nanocone. The ultimate efficiency of the optimal PENC array is 24.3%, which is 17.4% higher than that of the optimal CNC one with the same nanocone height and 59.1% higher than that of the flat counterpart coated with a 70 nm zinc-oxide antireflection film. When the nanocone height is between 0.3 and 5.0 μm and the incident angle is between 0° and 80°, the PENC array demonstrates better light trapping property compared with the CNC ones.
基于硅纳米线的阵列已展现出卓越的光捕获特性以及在下一代光伏领域的巨大潜力。在本文中，我们提出了一种垂直椭圆纳米锥（PENC）阵列太阳能电池，它除了具有在垂直于阵列表面方向上的不对称性（这已在圆形纳米锥（CNC）阵列中实现）之外，还在平行于阵列表面的方向上引入了不对称性。与CNC阵列相比，PENC阵列在长波长下显示出更多且更高的共振吸收峰。新出现的吸收峰被发现源自PENC阵列的能带折叠所产生的周期性布洛赫模式以及椭圆纳米锥不对称性所引入的腔模。最优PENC阵列的极限效率为24.3%，比具有相同纳米锥高度的最优CNC阵列高出17.4%，比涂覆有70纳米氧化锌抗反射膜的平面电池高出59.1%。当纳米锥高度在0.3至5.0微米之间且入射角在0°至80°之间时，PENC阵列与CNC阵列相比展现出更好的光捕获特性。
