Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
Nanoscale. 2012 Feb 21;4(4):1336-43. doi: 10.1039/c2nr11634k. Epub 2012 Jan 20.
We fabricated three-dimensional silicon nanopillar array (SiNP)-based photovoltaic (PV) devices using PbS quantum dots (QDs) as the hole-transporting layers. The core-shell structured device, which is based on high aspect ratio SiNPs standing on roughed silicon substrates, displays a higher PV performance with a power conversion efficiency (PCE) of 6.53% compared with that of the planar device (2.11%). The enhanced PCE is ascribed to the increased light absorption and the improved charge carrier collections in SiNP-modified silicon surfaces. We also show that, for the core-shell structured device, the thickness of the shell layer plays a critical role in enhancing the PV performance and around five monolayers of QDs are preferred for efficient hole-transporting. Wafer-scale PV devices with a radial PbS/SiNP heterojunction can be fabricated by solution phase techniques at low temperatures, suggesting a facile route to fabricate unique three-dimensional nanostructured devices.
我们使用 PbS 量子点 (QDs) 作为空穴传输层，制造了基于三维硅纳米柱阵列 (SiNP) 的光伏 (PV) 器件。基于高纵横比 SiNPs 站立在粗糙硅衬底上的核壳结构器件，与平面器件 (2.11%) 相比，显示出更高的 PV 性能，其功率转换效率 (PCE) 为 6.53%。增强的 PCE 归因于增加的光吸收和改进的在 SiNP 修饰的硅表面的载流子收集。我们还表明，对于核壳结构器件，壳层的厚度在增强 PV 性能方面起着关键作用，并且大约五层的 QDs 是用于有效空穴传输的优选厚度。通过低温的溶液相技术可以制造具有径向 PbS/SiNP 异质结的晶圆级 PV 器件，这表明了制造独特的三维纳米结构器件的简便途径。
