The power conversion efficiency of the perovskite solar cell is high enough to be commercially viable. However, long-term stability is the inevitable issue that obstructs its commercialization. Here, we demonstrate that the half-year (∼4680 h) stable unencapsulated inverted solar cell has almost zero loss in performance, measured under controlled environmental condition, when using montmorillonite (MMT)/CH₃NH₃PbI₃ nanocomposite as photoactive layer. It yields up to 17.29% in power conversion efficiency, owing to the formation of an outstandingly dense gas permeation barrier of exfoliated MMT shell that effectively retards the moisture from penetrating into the perovskite. It is believed that this extensively modified device and low-cost architecture will compellingly lead to the timely commercialization of perovskite solar cells.

中文翻译：

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通过使用蒙脱土/ CH ₃ NH ₃ PbI ₃纳米复合材料作为光敏层来增强超稳定的未封装钙钛矿型太阳能电池†

钙钛矿太阳能电池的功率转换效率足够高以使其在商业上可行。但是，长期稳定性是阻碍其商业化的必然问题。在这里，我们证明了在使用蒙脱石（MMT）/ CH ₃ NH ₃ PbI _3的情况下，在受控环境条件下，半年（约4680 h）稳定的未封装倒置太阳能电池的性能损失几乎为零。纳米复合材料作为光敏层。由于剥落的MMT外壳形成了非常致密的气体渗透屏障，可有效阻止水分渗透到钙钛矿中，因此其功率转换效率高达17.29％。可以相信，这种经过广泛修改的设备和低成本的体系结构将有力地促使钙钛矿太阳能电池的及时商业化。