自由基分子缓冲网络减少FAPbI₃钙钛矿太阳能电池的光电压损失

Radical Molecular Network-Buffer Minimizes Photovoltage Loss in FAPbI₃ Perovskite Solar Cells. Adv. Mater. 2025, 2417289.

      FAPbI₃钙钛矿太阳能电池在高效光伏方面具有巨大潜力。然而大尺寸甲脒离子(FA⁺)导致的晶格畸变问题长期未解决。尤其{111}c晶面生长过程中易形成平行于基底的晶内平面缺陷。这些缺陷不仅阻碍电荷垂直传输，还会引发非辐射复合，导致器件的开路电压(V_OC)和填充因子(FF)显著降低。鉴于此。2025年2月24日，南京工业大学王芳芳教授和武汉理工大学李蔚教授于Adv. Mater.刊发使用具有可原位聚合的自由基分子ATEMPO作为添加剂来解决这些问题。ATEMPO 优先与 {111}_c 钙钛矿面相互作用，引导它们的生长并在聚合时形成“自由基分子网络缓冲区”。该网络有效地减轻了晶格应变，抑制了缺陷的形成，通过氧化还原增强了电荷传输，并提供了疏水屏障，显著提高了器件的防潮性。这种策略产生了高质量、面向 {111}_c 的 FAPbI₃ 薄膜，从而产生了 25.28% 的冠军 PCE，V_OC 高达 1.203 V，能量损失仅有 0.297 eV ，这是已报道的 FAPbI₃ 钙钛矿最高 VOC 之一。此外，有效面积为 12.5 cm² 的微型模块实现了 21.39% 的 PCE。这项工作为开发高性能、稳定的 钙钛矿太阳能电池 铺平了道路，并且光电压损失最小。此外，它还提供了一种很有前景的策略来延长设备寿命和解决环境问题。

      Formamidinium lead iodide (FAPbI₃) perovskite solar cells (PSCs) hold immense potential for high-efficiency photovoltaics, but maximizing their open-circuit voltage (V_OC) remains challenging. Targeting the inherently stable {111}_c-dominant facets is a promising approach for enhancing stability, but their formation typically suffers from high defect densities and disordered growth. This study introduces a novel approach using an in situ polymerizable radical molecule, ATEMPO, as an additive to address these issues. ATEMPO preferentially interacts with the {111}_c perovskite facets, guiding their growth and forming a “radical molecular network-buffer” upon polymerization. The network effectively mitigates lattice strain, suppresses defect formation, enhances charge transport via redox-mediated hopping, and provides a hydrophobic barrier, significantly improving moisture resistance. This strategy yields high-quality, {111}_c-oriented FAPbI₃ films, leading to a champion PCE of 25.28% with a remarkably high V_OC of 1.203 V, corresponding to an energy loss (Eloss) of only 0.297 eV, among the highest V_OC reported for FAPbI₃-based PSCs. Furthermore, a mini-module fabricate with an active area of 12.5 cm² achieve a high PCE of 21.39%. the work paves the way for developing high-performance, stable PSCs with minimized photovoltage loss. Furthermore, it offers a promising strategy to enhance device longevity and address environmental concerns.

原文：

https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202417289