Itzhak Anat, He Xu, Kama Adi, Kumar Sujit, Ejgenberg Michal, Kahn Antoine, Cahen David
Department of Chemistry and Bar-Ilan Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat Gan5290002, Israel.
Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey08544, United States.
ACS Appl Mater Interfaces. 2022 Oct 26;14(42):47587-47594. doi: 10.1021/acsami.2c11701. Epub 2022 Oct 13.
The interfaces between inorganic selective contacts and halide perovskites (HaPs) are possibly the greatest challenge for making stable and reproducible solar cells with these materials. NiO, an attractive hole-transport layer as it fits the electronic structure of HaPs, is highly stable and can be produced at a low cost. Furthermore, NiO can be fabricated via scalable and controlled physical deposition methods such as RF sputtering to facilitate the quest for scalable, solvent-free, vacuum-deposited HaP-based solar cells (PSCs). However, the interface between NiO and HaPs is still not well-controlled, which leads at times to a lack of stability and losses. Here, we use RF sputtering to fabricate NiO and then cover it with a NiN layer without breaking vacuum. The NiN layer protects NiO doubly during PSC production. Firstly, the NiN layer protects NiO from Ni species being reduced to Ni by Ar plasma, thus maintaining NiO conductivity. Secondly, it passivates the interface between NiO and the HaPs, retaining PSC stability over time. This double effect improves PSC efficiency from an average of 16.5% with a 17.4% record cell to a 19% average with a 19.8% record cell and increases the device stability.
无机选择性接触与卤化物钙钛矿（HaP）之间的界面可能是使用这些材料制造稳定且可重复的太阳能电池面临的最大挑战。氧化镍（NiO）是一种有吸引力的空穴传输层，因为它符合HaP的电子结构，具有高度稳定性且成本低廉。此外，NiO可以通过诸如射频溅射等可扩展且可控的物理沉积方法制备，以推动对可扩展、无溶剂、真空沉积的基于HaP的太阳能电池（PSC）的探索。然而，NiO与HaP之间的界面仍未得到很好的控制，这有时会导致稳定性不足和损失。在此，我们使用射频溅射制备NiO，然后在不破坏真空的情况下用氮化镍（NiN）层覆盖它。NiN层在PSC生产过程中对NiO起到双重保护作用。首先，NiN层保护NiO免受氩等离子体将镍物种还原为镍的影响，从而保持NiO的导电性。其次，它钝化了NiO与HaP之间的界面，使PSC随时间保持稳定性。这种双重作用将PSC的效率从平均16.5%（记录电池为17.4%）提高到平均19%（记录电池为19.8%），并提高了器件的稳定性。
