Solution-producible depleted heterojunction solar cells made of copper indium disulfide and zinc oxide nanocrystals

由可溶液加工的半导体纳米晶体制成的太阳能电池是从有机光致发光领域中新兴的技术，并且近年来取得了迅速的发展。最有前景的概念采用p型吸收剂纳米颗粒和n型过渡金属氧化物之间的异质结。在这样的异质结中，耗尽区在界面处形成，导致能带弯曲，这有助于分离光生电子-空穴对。在最近的文献中，已经报道了使用硫化铅（PbS）和二氧化钛（TiO 2）时超过9%的功率转换效率。然而，目前国际上的研究主要集中在高毒性铅基吸收材料上，这是一个严重的缺点。因此，本项目的目的是研究和开发具有替代材料系统的太阳能电池，namley具有在铜铟二硫化物（CuInS 2）纳米晶体的溶液可产生吸收层和氧化锌（ZnO）纳米晶体的溶液可加工层之间形成的异质结。从初步的工作，已经证明了工作原理，深入的物理理解的限制基本过程将产生系统的实验，并进一步探讨潜在的CuInS 2/ZnO系统作为一种替代已建立的纳米粒子太阳能电池与铅硫族化物。

Solar cells made of solution-processable semiconductor nanocrystals are a technology emerging from the field of organic photovoltaics and have made rapid progress in recent years. The most prospective concept employs a heterojunction between p-type absorber nanoparticles and an n-type transition metal oxide. In such a heterojunction, a depletion zone is formed at the interface, causing band bending which helps to separate photo-generated electron-hole pairs. With lead sulfide (PbS) and titanium dioxide (TiO2), over 9% power conversion efficiency have been reported in recent literature. However, the common approach has the serious disadvantage, that international research was focused on highly toxic Pb-based absorber material, so far. Therefore, the aim of the present project is to examine and develop nanocrystal solar cells with an alternative material system, namley with a heterojunction formed between a solution-producible absorber layer of copper indium disulfide (CuInS2) nanocrystals and a solution-processable layer of zinc oxide (ZnO) nanocrystals. Starting from preliminary work which demonstrated already the working principle, deep physical understanding of limiting elementary processes will be generated by systematic experiments, and the further potential of the CuInS2/ZnO system as an alternative to established nanoparticle solar cells with lead chalcogenides will be explored.