近日，深圳职业技术大学胡汉林团队揭示了Knoevenagel缩合为高效宽带隙钙钛矿和串联光伏提供了高偶极子界面分子。相关论文于2025年10月28日发表在《德国应用化学》杂志上。

界面修饰剂的理性分子设计对于优化宽禁带钙钛矿太阳能电池的电荷传输与缺陷钝化至关重要。

研究组通过Knoevenagel缩合反应合成了一种新型多功能分子(Z)-4-(2-(4-溴苯基)-2-氰基乙烯基)苯胺（BCPA），其具有高极性特征，基态偶极矩高达18.16德拜，显著超越基准材料Me-4PACz（1.60德拜）。这种显著极性源于电正性铵基（─NH₃⁺）与电负性氰基（─CN）和溴取代基（─Br）的协同作用，共同强化了界面偶极-基底相互作用。其中─CN基团可与NiO_x中的Ni^x+及钙钛矿中的P^b2+配位，有效钝化电子缺陷并调控自组装分子锚定行为；─NH₃⁺基团则与钙钛矿晶格形成稳定键合，调控晶体生长动力学并改善界面接触；溴原子确保了与富溴宽禁带钙钛矿的本征相容性。

值得注意的是，BCPA的刚性平面结构通过π-π相互作用促进自组装分子有序堆积，从而增强界面电荷提取能力。经BCPA修饰的空穴传输层通过降低陷阱密度、提升结晶性及能级匹配，显著改善了钙钛矿/基底埋底界面质量。最终，修饰后的宽禁带钙钛矿太阳能电池实现了19.08%的冠军效率，并具有增强的稳定性。进一步应用于钙钛矿-有机叠层器件时，其能量转换效率达到26.10%，凸显了界面修饰剂在新一代高效光伏技术中的关键作用。

附：英文原文

Title: Knoevenagel Condensation Enables a High-Dipole Interfacial Molecule for Efficient Wide-Bandgap Perovskite and Tandem Photovoltaics

Author: Xianfang Zhou, Yonggui Sun, Baolei Tang, Fei Wang, Xiaoman Ding, Haoran Lin, Yao Tong, Xiaoqing Liu, Huajun Sun, Quanyao Zhu, Chunming Yang, Zhiwei Ren, Mingjian Yuan, Gang Li, Hongyu Zhang, Hanlin Hu

Issue&Volume: 2025-10-28

Abstract: The rational molecular design of interfacial modifiers is critical for optimizing charge transport and defect passivation in wide-bandgap (WBG) perovskite solar cells (PSCs). Herein, we introduce a novel multifunctional molecule, (Z)-4-(2-(4-bromophenyl)-2-cyanovinyl) phenylamine (BCPA), synthesized via Knoevenagel condensation reaction, featuring a highly polar architecture with a ground-state dipole moment of 18.16 Debye, significantly exceeding that of the benchmark Me-4PACz (1.60 Debye). This pronounced polarity stems from a synergistic combination of an electropositive ammonium group (─NH3) and electronegative cyano (─CN) and bromine (─Br) substituents, which collectively foster strong interfacial dipole–substrate interactions. The ─CN moiety coordinates with Ni in NiOX and Pb2 in perovskites, effectively passivating electronic defects and modulating self-assembled molecules (SAM) anchoring. Meanwhile, the ─NH3 group forms stable bonds with perovskite lattice, modulating crystal growth kinetics, and improving interfacial contact. The Br atom ensures intrinsic compatibility with bromine-rich wide-bandgap perovskites. Notably, the rigid, planar structure of BCPA facilitates ordered SAM packing via π–π interactions, enhancing interfacial charge extraction. BCPA-modified hole transport layers significantly improve the buried perovskite/substrate interface by reducing trap densities, enhancing crystallinity, and aligning energy levels. As a result, modified WBG PSCs realized a champion efficiency of 19.08% with reinforced durability. Furthermore, when applied in perovskite-organic tandem configurations, the devices reach a remarkable PCE of 26.10%, highlighting the importance of interfacial modifier for next-generation high-efficiency photovoltaics.

DOI: 10.1002/anie.202518169

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202518169