The present work deals with an advanced technology for efficient light management through back reflection in thin silicon based solar cells, in particular, single-junction microcrystalline silicon (μc-Si:H) solar cells. Semiconductor nanoparticles (Ag2S NPs) have been chosen to design the back reflector layer (BRL) by embedding them within two thin layers of indium tin oxide (ITO). Owing to its nominal parasitic light absorption over a broad wavelength region (300–1100 nm), the Ag2S NPs can reflect back a notable amount of light that were supposed to get transmitted through the relatively less thick (∼2 μm) active microcrystalline Si layer, and hence, can function like nanomirrors. Encapsulation of the Ag2S NPs between the ITO layers provides chemical and physical stability to the nanomirrors. By placing such BRL at the back of this p-i-n based superstrate structure, a significant amount of light (>90%), mainly in the red and near infrared (NIR) region, was found to reflect back to the cell and this resulted in a state-of-the-art photoconversion efficiency of 9.36% for single-junction μc-Si:H solar cells. The reported value is one of the best in the class. As the main light absorption zone for μc-Si:H falls in the red and NIR region (bandgap energy of μc-Si:H is 1.1–1.2 eV), such back reflections become worthy. The experimentally observed facts have also been validated through theoretical simulations.

中文翻译：

---

用于先进单结 μc-Si:H 太阳能电池中高级光学管理的堆叠背反射器架构

目前的工作涉及通过薄硅基太阳能电池，特别是单结微晶硅 (μc-Si:H) 太阳能电池的背反射进行高效光管理的先进技术。已选择半导体纳米粒子 (Ag2S NP) 来设计背反射层 (BRL)，方法是将它们嵌入两层氧化铟锡 (ITO) 薄层中。由于其在宽波长范围（300-1100 nm）上的标称寄生光吸收，Ag2S NPs 可以反射回显着量的光，这些光应该通过相对较薄（~2 μm）的活性微晶硅层透射，因此，可以像纳米镜一样发挥作用。在 ITO 层之间封装 Ag2S NP 为纳米镜提供了化学和物理稳定性。通过将这种 BRL 放置在这种基于引脚的覆层结构的背面，发现大量光 (>90%)，主要是在红色和近红外 (NIR) 区域，反射回电池，这导致单结 μc-Si:H 太阳能电池的最先进光转换效率为 9.36%。报告的值是同类中最好的值之一。由于 μc-Si:H 的主要光吸收区落在红色和 NIR 区域（μc-Si:H 的带隙能量为 1.1-1.2 eV），因此这种背反射变得有价值。实验观察到的事实也通过理论模拟得到了验证。36% 用于单结 μc-Si:H 太阳能电池。报告的值是同类中最好的值之一。由于 μc-Si:H 的主要光吸收区落在红色和 NIR 区域（μc-Si:H 的带隙能量为 1.1-1.2 eV），因此这种背反射变得有价值。实验观察到的事实也通过理论模拟得到了验证。36% 用于单结 μc-Si:H 太阳能电池。报告的值是同类中最好的值之一。由于 μc-Si:H 的主要光吸收区落在红色和 NIR 区域（μc-Si:H 的带隙能量为 1.1-1.2 eV），因此这种背反射变得有价值。实验观察到的事实也通过理论模拟得到了验证。