In recent years, self-assembled monolayers (SAMs) anchored on metal oxides (MO) have greatly boosted the performance of inverted (p-i-n) perovskite solar cells (PVSCs) by serving as hole-selective contacts due to their distinct advantages in transparency, hole-selectivity, passivation, cost-effectiveness, and processing efficiency. While the intrinsic monolayer nature of SAMs provides unique advantages, it also makes them highly sensitive to external pressure, posing a significant challenge for long-term device stability. At present, the stability issue of SAM-based PVSCs is gradually attracting attention. In this review, we discuss the fundamental stability issues arising from the structural characteristics, operating mechanisms, and roles of SAMs, and highlight representative works on improving their stability. We identify the buried interface stability concerns in three key aspects: 1) SAM/MO interface, 2) SAM inner layer, and 3) SAM/perovskite interface, corresponding to the anchoring group, linker group, and terminal group in the SAMs, respectively. Finally, we have proposed potential strategies for achieving excellent stability in SAM-based buried interfaces, particularly for large-scale and flexible applications. We believe this review will deepen understanding of the relationship between SAM structure and their device performance, thereby facilitating the design of novel SAMs and advancing their eventual commercialization in high-efficiency and stable inverted PVSCs.

中文翻译：

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高效 SAM 基倒置钙钛矿太阳能电池的埋地界面稳定策略


近年来，锚定在金属氧化物 （MO） 上的自组装单层 （SAM） 由于在透明度、空穴选择性、钝化、成本效益和加工效率方面具有明显的优势，通过作为空穴选择性接触，大大提高了倒置 （p-i-n） 钙钛矿太阳能电池 （PVSC） 的性能。虽然 SAM 的固有单层性质提供了独特的优势，但它也使它们对外部压力高度敏感，对器件的长期稳定性构成了重大挑战。目前，基于 SAM 的 PVSC 的稳定性问题逐渐受到关注。在本文中，我们讨论了 SAM 的结构特性、运行机制和作用引起的基本稳定性问题，并重点介绍了提高其稳定性的代表性工作。我们从三个关键方面确定了埋藏界面稳定性问题：1） SAM/MO 界面，2） SAM 内层，以及 3） SAM/钙钛矿界面，分别对应于 SAM 中的锚定基团、连接子基团和末端基团。最后，我们提出了在基于 SAM 的埋点接口中实现出色稳定性的潜在策略，特别是对于大规模和灵活的应用。我们相信，本文将加深对 SAM 结构与其器件性能之间关系的理解，从而促进新型 SAM 的设计，并推动其最终在高效、稳定的倒置 PVSC 中的商业化。