Zhang Xianfu, Li Botong, Zhang Shaochen, Lin Zedong, Han Mingyuan, Liu Xuepeng, Chen Jianlin, Du Weilun, Rahim Ghadari, Zhou Ying, Shi Pengju, Wang Rui, Wu Pengfei, Alshahrani Thamraa, Alqahtani Wadha, Alahmad Norah, Wang Qian, Ding Bin, Dai Songyuan, Nazeeruddin Mohammad Khaja, Ding Yong
Beijing Key Laboratory of Novel Thin-Film Solar Cells, North China Electric Power University Beijing 102206 China
Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne CH-1015 Switzerland
Energy Environ Sci. 2024 Nov 27;18(1):468-477. doi: 10.1039/d4ee01960a. eCollection 2025 Jan 2.
Self-assembled monolayers (SAMs) have significantly contributed to the advancement of hole transporting materials (HTMs) for inverted perovskite solar cells (PSCs). However, uneven distribution of SAMs on the substrate largely decreases the PSC performance, especially for large-scale devices. Herein, the first spiro-type SAM, termed 4PA-spiro, with an orthogonal spiro[acridine-9,9'-fluorene] as the skeleton and phosphonic acid as the anchoring group were proposed. Compared to the reference 4PACz, the twisted configuration with larger steric hindrance of 4PA-spiro inhibited the intermolecular aggregation, enabling a uniform and homogeneous anchoring on the substrate. Moreover, the suitable highest occupied molecular orbital (HOMO) level of 4PA-spiro is beneficial in promoting hole extraction and reducing charge non-radiative recombination. As a result, compared to 4PACz with a power conversion efficiency (PCE) of 22.10%, the 4PA-spiro-based PSCs exhibited a superior PCE of 25.28% (certified 24.81%, 0.05 cm), along with excellent long-term stability. More importantly, 4PA-spiro-enabled larger-area PSCs and modules achieved PCEs of 24.11% (1.0 cm) and 21.89% (29.0 cm), respectively, one of the highest PCEs for inverted PSC modules, providing an effective SAM candidate for the commercialization of efficient, stable and large-scale inverted PSCs.
自组装单分子层（SAMs）对倒置钙钛矿太阳能电池（PSC）的空穴传输材料（HTMs）的发展做出了重大贡献。然而，SAMs在基底上的分布不均会大大降低PSC的性能，特别是对于大规模器件而言。在此，我们提出了第一种螺环型SAM，称为4PA-螺环，它以正交螺环[吖啶-9,9'-芴]为骨架，膦酸为锚定基团。与参考物4PACz相比，具有较大空间位阻的扭曲构型的4PA-螺环抑制了分子间聚集，使其能够在基底上均匀且同质地锚定。此外，4PA-螺环合适的最高占据分子轨道（HOMO）能级有利于促进空穴提取并减少电荷非辐射复合。结果，与功率转换效率（PCE）为22.10%的4PACz相比，基于4PA-螺环的PSC表现出25.28%的优异PCE（认证值为24.81%，面积0.05平方厘米），同时具有出色的长期稳定性。更重要的是，采用4PA-螺环的大面积PSC和组件分别实现了24.11%（面积1.0平方厘米）和21.89%（面积29.0平方厘米）的PCE，这是倒置PSC组件的最高PCE之一，为高效、稳定和大规模倒置PSC的商业化提供了一种有效的SAM候选物。
