【作者】 白赛；

【导师】 金一政；

【作者基本信息】 浙江大学 ， 材料物理与化学， 2014， 博士

【摘要】 本论文以溶液工艺的光电器件中的金属氧化物界面层为研究对象,以太阳能电池器件为主要载体,在优化活性层的基础上,重点研究基于胶体纳米晶及前驱体溶液低温工艺制备的n型氧化锌(ZnO)和p型氧化镍(NiO)薄膜界面层在有机太阳能电池以及钙钛矿有机-无机杂化型太阳能电池中的应用及界面特性。从材料体系、成膜工艺、表面修饰等多角度开展了一系列创新工作,并为材料和器件的进一步优化提供了思路。文中主体工作基于胶体ZnO纳米晶开展。基于对胶体ZnO纳米晶材料带电特性的理解,我们开发出一种室温电泳沉积的方法用于制备ZnO纳米晶薄膜。通过优化沉积条件,制备出均匀致密、厚度可控的ZnO纳米晶薄膜并将其应用于有机光电器件。基于对ZnO纳米晶薄膜表面缺陷态的理解,我们引入一种新型的小分子表面修饰方法,即用乙二硫醇钝化ZnO表面缺陷态,有效调控了薄膜内部多种缺陷态所引入的复杂能带结构,构建了更为有效的电子传输通道。该表面钝化方法显著降低了反型有机太阳能电池内部的载流子复合速率,改善了界面层对空气中水、氧的敏感程度,从而有效提升了器件效率和空气稳定性。该研究为ZnO表面缺陷态的修饰提供了新的认知和思路。同时我们也发现通过合金化手段能够有效调节ZnO纳米晶材料的能带结构,进而可以针对光电器件中所使用的材料体系为其量身定制更为匹配的电子传输层界面。对于钙钛矿有机-无机杂化电池体系,我们从钙钛矿薄膜本身入手,系统研究了后处理温度及成膜工艺条件对于薄膜表面形貌、结晶质量及载流子扩散距离等参数的影响。针对反型平面异质结器件结构稳定性差的难题,我们通过引入室温成膜的ZnO纳米晶薄膜有效改善了阴极界面,从而显著提升了器件性能和空气稳定性,为钙钛矿太阳能电池的薄膜质量控制及器件结构的优化提供了重要依据。本文也基于原位合成金属氧化物薄膜的前驱体溶液体系开展了相关研究,我们分别基于氨水络合物和溶液燃烧法的思路开发出了低温制备ZnO和NiO薄膜的水相前驱体溶液体系,并系统研究了所得两种氧化物薄膜的表面特性及其在有机光电器件中的应用。更多还原

【Abstract】 This thesis investigates solution-processed metal oxide charge transport interlayers for optoelectronic devices. We focus on low temperature processed n-type zinc oxide (ZnO) and p-type nickel oxide (NiO) thin films, deposited from either colloidal nanocrystal or so-gel precursor solutions. New materials, novel deposition technology and innovative surface passivation strategy developed in this thesis provide novel thoughts for the application and optimization of the metal oxide-based optoelectronic devices.Primary works involved in this thesis are based on ZnO colloidal nanocrystal films. Based on our understanding on charging nature of ZnO nanocrystal, we developed a room-temperature electrophoretic deposition method to fabricate ZnO nanocrystal films, which were applied to organic electronics field. We introduced a small-molecule modification approach to passivate the surface defects of ZnO films. Upon the covalent bonds formed near surface, various gap states formed by the complex surface groups can be uniformed to a novel efficient electron transport channel. And hence the charge carrier recombination in devices and the sensitivity to oxygen and water of inverted organic solar cells can be further reduced. We find that the band structures of thin films based on ZnO nanocrystals can be efficiently tuned by alloying, which make it possible to customize interlayers for various organic materials used in the optoelectronic devices.For hybrid perovskite solar cells, we investigated the influence of processing conditions on surface morphology, crystalline quality and charge carrier diffusion lengths of the perovskite films. We further modified the cathode interface by integrating a room-temperature deposited ZnO nanocrystal interlayer. Device performance and air stability were significantly improved by optimizing the device structure.Based on zinc-ammonia complex and solution-combustion reactions, we designed new aqueous solutions to fabricate ZnO and NiO thin films at low temperatures, respectively. Surface properties of two kinds of interlayers and their applications in organic optoelectronics were also investigated.更多还原