【作者】 王政；

【导师】 张海昌；

【作者基本信息】 青岛科技大学 ， 高分子化学与物理， 2025， 硕士

【摘要】 小分子空穴传输材料因具备优良的可加工性与器件兼容性,在钙钛矿太阳能电池中具有突出优势。然而,小分子空穴传输材料自身稳定性差、易发生离子迁移等问题仍限制其进一步发展。此外,小分子空穴传输材料的抵抗溶剂溶解能力普遍不足,尤其在反式器件结构中,钙钛矿前驱体溶液不可避免会溶解空穴传输材料的表面进而导致层间互相渗透并影响长期器件性能。因此设计并合成新型空穴传输材料是提升钙钛矿太阳能电池性能并促进其大范围实际应用的关键。基于此,本工作第一项研究合成了三种O1-O3空穴传输材料,系统考察了氢键诱导H聚集对材料性质的影响,该系列空穴传输材料对电荷迁移率和界面特性表现出一种权衡效应,尽管引入氢键单元可有效增强材料的界面稳定性与抗溶解能力,但在本研究体系中,未引入氢键的O1材料表现出更高的空穴迁移率与器件效率。同时,虽然氢键功能化空穴传输材料O2和O3显著增强了钙钛矿器件的长期稳定性,但由于氢键作用力导致分子间三苯胺单元堆积能力变弱,进而导致层内载流子传递能力不足降低了器件的性能。因此O1-O3空穴传输材料展现出在效率与稳定性之间明显的权衡效应并为含氢键空穴传输材料的设计提供了理论指导。在第二项研究中,为解决小分子空穴传输材料中的关键挑战,即针对它们易受离子迁移的影响以及界面接触不良的问题,开发了一种创新的原位反应空穴传输材料策略。首先设计并合成了新一代小分子空穴传输材料CAZ-NCS,同时在钙钛矿前驱体溶液中引入聚合物添加剂P-Apronal(聚丙戊酰脲),二者原位反应形成的CAZ-NCS-P网络有效弥合了钙钛矿与空穴传输层间的缺陷界面,增强了界面接触与能级匹配。这一策略不仅改善了界面空穴提取,还有效地抑制了离子迁移,从而显著提高了器件效率和稳定性。基于CAZ-NCS-P的反式钙钛矿太阳能电池器件达到23.52%的能量转换效率。此外,在空气环境中,600小时的最大功率点追踪后仍保留了94%的初始能量转化效率,表现出了较高的稳定性。综上所述,这两项研究提供了互补的方法来增强钙钛矿太阳能电池中小分子空穴传输材料的性能和稳定性。第一项研究强调了控制H聚集对于优化电荷传输和界面稳定性的重要性,而第二项研究则介绍了一种新颖的策略,用于原位形成坚固的空穴传输网络,以解决离子迁移和界面降解问题。总而言之,本研究旨在为小分子空穴传输材料的设计提供一定见解,并进一步提升钙钛矿太阳能电池器件的性能与稳定性。更多还原

【Abstract】 Small-molecule hole transport materials(HTMs)have shown significant advantages in the development of perovskite solar cells,particularly in terms of material processability,scalability,and ease of integration into device architectures.However,in inverted perovskite solar cell devices,small-molecule HTMs often face design challenges such as poor interfacial stability and ion migration.Additionally,small-molecule HTMs generally lack sufficient resistance to solvent dissolution,especially in inverted device structures,where the perovskite precursor solution inevitably dissolves the surface of the HTM,leading to interlayer penetration and hindering long-term device performance.Therefore,the design and synthesis of novel HTMs are crucial to improving the performance of perovskite solar cells and promoting their large-scale practical applications.Based on this,the first part of this study involves the design and synthesis of three different HTMs:O1(without hydrogen bonding),O2(with single-side hydrogen bonding units),and O3(with double-side hydrogen bonding units).The study explores the properties of hydrogen-bond-induced H-aggregation in organic small-molecule HTMs.This series of HTMs exhibits a trade-off effect between charge mobility and interfacial properties.Although the hydrogen-bond units positively affect interfacial stability and dissolution resistance,the O1 HTM,which lacks hydrogen bonding units,exhibits the highest hole mobility and best performance in inverted perovskite solar cell devices.Additionally,although hydrogen-bond functionalized HTMs(O2 and O3)significantly enhance the long-term stability of perovskite devices,the hydrogen bonding weakens the stacking ability of the triphenylamine units between molecules,which in turn reduces carrier transport within the layers and lowers the overall device performance.Therefore,the O1-O3 HTMs exhibit a clear trade-off effect between efficiency and stability,providing theoretical guidance for the design of hydrogen-bonded HTMs.In the second part of the study,to address key challenges in small-molecule HTMs specifically their susceptibility to ion migration and poor interfacial contact—a novel in-situ reaction strategy for HTMs is developed.The new generation of small-molecule HTMs,CAZ-NCS,is designed and synthesized,and a polymer additive,P-Apronal,is introduced into the perovskite precursor solution.The isothiocyanate groups in CAZ-NCS react in situ with the high-density amine groups at the terminal ends of P-Apronal,forming a hole transport network(CAZ-NCS-P)that spans the perovskite layer and the HTM.This network effectively overcomes the typical defect-rich interface between the perovskite and HTM layers,promoting stronger interfacial contact and improving energy level alignment.This innovative strategy not only enhances hole extraction at the interface but also significantly suppresses ion migration,thereby improving device efficiency and stability.The inverted perovskite solar cell based on CAZ-NCS-P exhibits a power conversion efficiency of up to 23.52%.Moreover,the device demonstrates exceptional stability,retaining 94%of its initial energy conversion efficiency after 600 hours of maximum power point tracking.In conclusion,these two studies provide complementary approaches to enhancing the performance and stability of small-molecule HTMs in perovskite solar cells.The first study emphasizes the importance of controlling H-aggregation for optimizing charge transport and interfacial stability,while the second study introduces a novel strategy for in-situ forming a robust hole transport network to address ion migration and interfacial degradation.Both approaches offer valuable insights for the design of next-generation small-molecule HTMs and pave the way for more efficient and durable perovskite solar cell devices.更多还原