富勒烯和金属纳米粒子的有机/无机杂化薄膜的电化学制备及光限幅研究

Lasers inflict fatal health damage to body tissues and military electronic communication devices. In this regard, the development of laser protective optical limiting material is of great demand for social and national security. At present, fabrication technologies for organic optical limiting films are mainly based on conventional spin-coated of polymers or doped polymers. Nevertheless, molecular aggregation cannot be controlled, and the content of optical limiting unit in the film is low over spin-coated. This proposal is aimed at producing organic-inorganic hybrid films of fullerenes and metallic nanoparticles by electrochemical reactions, which combine fullerenes (reverse saturable absorption materials) and metallic nanoparticles (free carrier absorption materials) to fabricate high-performance hybrid optical limiting films. In this project, the perfect control of molecular aggregation and distribution of organic-inorganic hybrid material in the film will be achieved. Furthermore, the synergistic mechanism of reverse saturable absorption (fullerenes) and the free carrier absorption (metallic nanoparticles) will be studied. Finally, a low-cost fabrication technology of optical limiting films will be established and protected by independent intellectual-property rights.

激光对人体及一些军用电子通讯设备会产生致命的损害，发展对激光有防护作用的高性能光限幅材料是社会和国防安全的重大需求。现阶段有机光限幅薄膜制备主要是基于聚合物自身或与之掺杂的旋涂方法，难以实现功能单元在薄膜中的高比重及同时控制相互聚集。本项目将通过电化学方法制备富勒烯和金属纳米粒子的有机/无机杂化薄膜，结合富勒烯反饱和吸收和金纳米粒子的自由载流子吸收两种激光光限幅机理发展高性能的光限幅薄膜材料。本项目可以灵活地调控有机/无机杂化材料在薄膜中的分布和聚集形式，并且有益于研究反饱和吸收和自由载流子吸收两种光限幅协同作用机理，最终发展成具有自主知识产权的光限幅薄膜低成本制备技术。

本项目初始研究目标是通过电化学方法制备富勒烯/金纳米粒子的杂化薄膜，结合富勒烯反饱和吸收和金纳米粒子的自由载流子吸收两种激光光限幅机理发展高性能的光限幅材料。合成的复合组份薄膜的光限幅阈值低于单组分薄膜但光限幅效果并不突出，但让人意外的是它们具有热诱导延迟荧光(TADF)性质。因此本项目的重点调整为TADF聚合物的探索。TADF长波长(红光)材料的辐射跃迁速率随光学带隙减小呈指数型降低(能隙规则)，导致红光TADF聚合物的设计十分困难。. 本项目通过三个策略设计合成红光TADF聚合物：(1).基于主链给体/侧基受体(BDPA)策略，开展了基于聚(芴砜-alt-芴或2,7-咔唑)主链的红光TADF聚合物(PFSOTAQx和PCzSOTAQx)合成及性质表征。非掺杂器件都拥有超过传统OLED材料5%的最大外量子效率(EQE)。PFSOTAQ5最大EQE达到7.3%，且实现了CIE为(0.62,0.38)的纯红光发射。PCzSOTAQ2最大EQE达到13.6%，且实现了CIE为(0.62,0.37)的纯红光发射；(2).基于受体嵌入主链/给体为侧基的策略，成功合成了系列红光发射TADF聚合物PCzAQCx，实现627-661 nm红光发射的同时还可以保持最大PLQY为80%。PCzAQC0.5的EQE可达12.5%，将蓝光材料CzAcSF与之掺杂可制备出单发光层的暖白光发射器件，覆盖可见-近红外全光谱且EQE效率可高达22.4%；(3).基于受体为主链/给体为侧基(BAPD)策略，合成了系列聚合物PSAQFx。相对于AQF模型化合物，伸长的共轭受体骨架使聚合物实现了红光发射。刷新了基于TADF聚合物的OLED器件性能，首次获得发光波长超过600 nm且EQE高于20%的TADF聚合物。