Ahmad Zubair, Najeeb Mansoor Ani, Shakoor R A, Alashraf Abdulla, Al-Muhtaseb Shaheen A, Soliman Ahmed, Nazeeruddin M K
Center for Advanced Materials (CAM), Qatar University, P.O.Box 2713, Doha, Qatar.
Department of Chemical Engineering, College of Engineering, Qatar University, P.O.Box 2713, Doha, Qatar.
Sci Rep. 2017 Nov 13;7(1):15406. doi: 10.1038/s41598-017-15841-4.
Organic-inorganic halide perovskites have rapidly grown as favorable materials for photovoltaic applications, but accomplishing long-term stability is still a major research problem. This work demonstrates a new insight on instability and degradation factors in CHNHPbI perovskite solar cells aging with time in open air. X-ray photoelectron spectroscopy (XPS) has been used to investigate the compositional changes caused by device degradation over the period of 1000 hrs. XPS spectra confirm the migration of metallic ions from the bottom electrode (ITO) as a key factor causing the chemical composition change in the perovskite layer besides the diffusion of oxygen. XPS results are in good agreement with the crystallographic marks. Glow discharge optical emission spectrometry (GD-OES) has also been performed on the samples to correlate the XPS results. Based on the experimental results, fundamental features that account for the instability in the perovskite solar cell is discussed.
有机-无机卤化物钙钛矿已迅速成为光伏应用的理想材料，但实现长期稳定性仍是一个主要的研究问题。这项工作展示了对CH₃NH₃PbI₃钙钛矿太阳能电池在空气中随时间老化的不稳定性和降解因素的新见解。X射线光电子能谱（XPS）已被用于研究在1000小时内器件降解引起的成分变化。XPS光谱证实，除了氧气扩散外，金属离子从底部电极（ITO）迁移是导致钙钛矿层化学成分变化的关键因素。XPS结果与晶体学标记结果吻合良好。还对样品进行了辉光放电光发射光谱分析（GD-OES），以关联XPS结果。基于实验结果，讨论了导致钙钛矿太阳能电池不稳定性的基本特征。
