Alghamdi Amira R M, Yanagida Masatoshi, Shirai Yasuhiro, Andersson Gunther G, Miyano Kenjiro
Photovoltaic Materials Group, Center for GREEN Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
Flinders Institute for Nanoscale Science and Technology, Flinders University, P.O. Box 2100, Adelaide, SA 5001, Australia.
ACS Omega. 2022 Mar 30;7(14):12147-12157. doi: 10.1021/acsomega.2c00509. eCollection 2022 Apr 12.
Sputtered NiO (sp-NiO ) is a preferred hole transporting material for perovskite solar cells because of its hole mobility, ease of manufacturability, good stability, and suitable Fermi level for hole extraction. However, uncontrolled defects in sp-NiO can limit the efficiency of solar cells fabricated with this hole transporting layer. An interfacial layer has been proposed to modify the sp-NiO /perovskite interface, which can contribute to improving the crystallinity of the perovskite film. Herein, a 2-(3,6-dimethoxy-9-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz) self-assembled monolayer was used to modify an sp-NiO surface. We found that the MeO-2PACz interlayer improves the quality of the perovskite film due to an enlarged domain size, reduced charge recombination at the sp-NiO /perovskite interface, and passivation of the defects in sp-NiO surfaces. In addition, the band tail states are also reduced, as indicated by photothermal deflection spectroscopy, which thus indicates a reduction in defect levels. The overall outcome is an improvement in the device efficiency from 11.9% to 17.2% due to the modified sp-NiO /perovskite interface, with an active area of 1 cm (certified efficiency of 16.25%). On the basis of these results, the interfacial engineering of the electronic properties of sp-NiO /MeO-2PACz/perovskite is discussed in relation to the improved device performance.
溅射氧化镍（sp-NiO）因其空穴迁移率、易于制造、稳定性好以及适合空穴提取的费米能级，而成为钙钛矿太阳能电池首选的空穴传输材料。然而，sp-NiO中不受控制的缺陷会限制用这种空穴传输层制造的太阳能电池的效率。有人提出用一个界面层来修饰sp-NiO/钙钛矿界面，这有助于提高钙钛矿薄膜的结晶度。在此，使用2-(3,6-二甲氧基-9-咔唑-9-基)乙基]膦酸（MeO-2PACz）自组装单分子层来修饰sp-NiO表面。我们发现，MeO-2PACz中间层提高了钙钛矿薄膜的质量，这是由于畴尺寸增大、sp-NiO/钙钛矿界面处的电荷复合减少以及sp-NiO表面缺陷的钝化。此外，光热偏转光谱表明，带尾态也减少了，这表明缺陷能级降低。总体结果是，由于修饰了sp-NiO/钙钛矿界面，器件效率从11.9%提高到了17.2%，有效面积为1平方厘米（认证效率为16.25%）。基于这些结果，结合器件性能的提高，讨论了sp-NiO/MeO-2PACz/钙钛矿电子特性的界面工程。
