标题： 揭示路易斯碱强度在缺陷钙钛矿小分子钝化中的作用 显示英文标题

标题： Unveiling the Role of Lewis Base Strength in Small-Molecule Passivation of Defect Perovskites

摘要： 钙钛矿材料因其高载流子迁移率、带隙可调性和卓越的光捕获能力，在一系列光电应用中具有高度前景，包括能量转换技术。然而，制造过程中产生的缺陷常常导致性能限制，如效率和稳定性受阻。这主要是由于与原始钙钛矿相比，晶体几何结构和能带结构元素（如费米能级、功函数和态密度）存在显著偏差。为了缓解这些问题，本研究探索了使用小分子路易斯碱对钙钛矿中的表面碘空位缺陷进行钝化，这种方法旨在抵消这些有害影响。在研究的N、P和O配位的苄基衍生物中，那些以膦酸基团作为未配位Pb(II)位点钝化剂的化合物表现出优异的电子结构特性。这通过降低费米能级、提高功函数和抑制表面陷阱态得以显著实现。通过靶向小分子钝化有效恢复电子特性，为缺陷钙钛矿材料的功能增强和效率提升提供了关键见解。 显示英文摘要

摘要： Perovskite materials are highly promising for a range of optoelectronic applications including energy conversion technologies, owing to their high charge-carrier mobilities, adaptability of bandgap tuning, and exceptional light-harvesting capabilities. Yet, defects that arise during manufacturing often lead to performance limitations such as hindered efficiency and stability. This is primarily due to significant deviations in crystal geometry and band structure elements such as the Fermi level, work function, and density of states, compared to pristine perovskite. To mitigate these issues, this study explored the passivation of surface iodide-vacancy defect in perovskite using small-molecule Lewis bases, an approach aims to counteract these detrimental effects. Among the examined N-, P- and O-coordinated benzyl derivatives, those featuring a phosphonic acid group as a passivator for the undercoordinated Pb(II) sites demonstrated outstanding electronic structure properties. This was notably achieved by lowering the Fermi level, increasing the work function, and suppressing surface trap states. The effective restoration of electronic properties achieved by targeted small molecule passivation provides crucial insights into enhanced functionality and efficiency for defect perovskite materials.