Abstract Spinel Nickel cobaltite oxide (NiCo2O4) have received great interest due to its usage in several industrial applications. The motivation of the present study is to explore the usefulness of spinel Nickel cobaltite oxide as inorganic charge transporting layer for standard perovskite solar cells (PSCs). This is the first demonstration of successful use of NiCo2O4 nanoparticles as hole transporting layer (HTL) in standard PSCs with the triple cation perovskite material. The synthesis of nanoparticles was done using a facile chemical precipitation method without the use of surfactant. The synthesized nanoparticles were characterized by the various techniques like X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), Field emission scanning electron microscopy (FE-SEM), and UV–vis spectroscopy (UV–vis). The co-ordination of Ni in Co3O4 matrix, as well as M+n O bond lengths, were confirmed by the XAS studies. The standard mesoporous PSCs were fabricated by spin-coating a thin layer of NiCo2O4 (120 nm), and fabricated PSCs show an esteemed power conversion efficiency (PCE) of >14% (under standard illumination conditions) and long-term stability (under ambient condition RH = 30–40%) as compared to the spiro-based PSCs. To improve the device performance further we also fabricated the PSCs using the interfacial hole transporting layer, presenting a PCE of >16% with almost negligible hysteresis that is comparable to the normal standard PSCs based on spiro-OMeTAD as HTL. The performance of PSCs was further analysed by Electrochemical Impedance Spectroscopy (EIS), Photoluminescence (PL), Time-resolved Photoluminescence (TrPL) studies. The results showed the reduced recombination resistance in the PSCs using NiCo2O4 as well as interfacial layer. These outcomes indicate the effectiveness of NiCo2O4 interlayer for stable and highly efficient perovskite solar cells.

中文翻译：

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低温、溶液处理的尖晶石 NiCo2O4 纳米粒子作为介观 nip 钙钛矿太阳能电池的有效空穴传输材料

摘要 尖晶石 钴酸镍 (NiCo2O4) 因其在多种工业应用中的使用而受到极大关注。本研究的动机是探索尖晶石钴酸镍氧化物作为标准钙钛矿太阳能电池 (PSC) 的无机电荷传输层的有用性。这是首次成功使用 NiCo2O4 纳米颗粒作为标准 PSC 中的空穴传输层 (HTL)，该材料具有三重阳离子钙钛矿材料。纳米粒子的合成使用简便的化学沉淀方法完成，不使用表面活性剂。通过X射线衍射（XRD）、X射线吸收光谱（XAS）、场发射扫描电子显微镜（FE-SEM）和紫外-可见光谱（UV-vis）等多种技术对合成的纳米颗粒进行表征。XAS 研究证实了 Co3O4 基体中 Ni 的配位以及 M+n O 键长。标准介孔 PSCs 是通过旋涂一层薄薄的 NiCo2O4 (120 nm) 制造的，并且制造的 PSCs 显示出>14% 的受人尊敬的功率转换效率 (PCE)（在标准照明条件下）和长期稳定性（在环境条件下）条件 RH = 30–40%）与基于螺环的 PSC 相比。为了进一步提高器件性能，我们还使用界面空穴传输层制造了 PSC，PCE 大于 16%，滞后几乎可以忽略不计，与基于 spiro-OMeTAD 作为 HTL 的正常标准 PSC 相当。通过电化学阻抗光谱 (EIS)、光致发光 (PL)、时间分辨光致发光 (TrPL) 研究进一步分析了 PSC 的性能。结果表明，使用 NiCo2O4 和界面层的 PSC 中的复合电阻降低。这些结果表明 NiCo2O4 中间层对于稳定高效的钙钛矿太阳能电池的有效性。