LEAPS-MPS: Investigation of Electrochromic Polymer Induced Plasmon Switching on Gold Nanocrystals and its Application for Smart Windows

在这个由美国国家科学基金会化学部资助的项目中，陈刚教授和他在中佛罗里达大学的学生将进行研究，旨在将电致变色聚合物与等离子体纳米粒子结合起来，构建一种性能更好的新型智能窗户。智能窗户可以选择性地调节太阳光的透射/反射，大大提高了生活的舒适性和安全性，大大降低了建筑物和汽车空调的能耗。智能窗的性能主要依赖于变色材料，高分子电致变色材料因其显色效率高、响应速度快、可加工性高等特点，具有很大的商业价值。然而，电致变色聚合物在高电化学电位作用下会变质。这种劣化会影响聚合物电致变色材料的长期可循环性，降低其颜色对比度，阻碍了聚合物电致变色材料的商业化。陈教授和他的学生将通过开发由等离子体纳米粒子和电致变色聚合物组成的混合材料来解决这一挑战，这种材料可用于制造具有改进颜色切换特性的智能窗口设备。该项目旨在向新一代展示智能材料研究，使其在未来的科学创新中发挥主导作用。陈教授计划让研究生和本科生，特别是在STEM领域未被充分代表的少数民族学生，以及高中生参与该项目，以扩大研究和参与导向的外展活动的融合。等离子体纳米粒子，包括金、银和铜，在它们的等离子体波长上有很强的光吸收和散射，可以从可见光到近红外进行合成调谐。电致变色聚合物的电激子性质强烈地依赖于它们的介电环境，因此很容易因电致变色聚合物在漂白和有色状态之间的转变所带来的介电变化而改变。等离子体纳米粒子的引入有望在很大程度上提高电致变色聚合物在不同状态下的颜色对比度，从而避免其可能的电化学劣化。该研究将进一步加深我们对电致变色聚合物诱导等离子体纳米粒子的等离子体开关行为的认识。由等离子体纳米粒子/电致变色聚合物混合纳米结构制成的智能窗口器件有望具有改进的颜色开关特性。从这项研究中获得的知识也将有助于设计许多其他基于等离子体的光学器件，用于控制和引导光，用于广泛的领域，如信息显示、防伪油墨和用于癌症治疗的光热系统。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In this project, funded by the Chemistry Division at NSF, Professor Gang Chen and his students at the University of Central Florida will perform studies that aim to integrate electrochromic polymer with plasmonic nanoparticles to build a new type of smart windows with improved performance. Smart windows, whose transmittance/reflection of sunlight can be selectively adjusted, can dramatically improve the comfortability and security of living, and drastically reduce the energy consumptions of air conditioning in buildings and automobile vehicles. The performance of smart windows mainly depends on chromic materials, and polymer electrochromic materials are of great commercial value because of their high coloration efficiency, fast response speed, and high processability. However, electrochromic polymers will deteriorate under high applied electrochemical potentials. The deterioration will affect their long-term cyclability and lower their color contrast, which prevents the commercialization of the polymer electrochromic materials. Professor Chen and his students will tackle this challenge by developing hybrid materials consisting of plasmonic nanoparticle and electrochromic polymer that can be used to fabricate smart-window devices with improved color-switching characteristics. This project intends to expose smart materials research for a new generation so that they will take a leading role in future scientific innovation. Prof. Chen plans to involve graduate and undergraduate students, especially underrepresented minority students in STEM fields, as well as high school students in the project to broaden the integration of research and participation-oriented outreach activities. Plasmonic nanoparticles, including gold, silver, and copper, have strong light absorption and scattering at their plasmon wavelengths, which can be synthetically tuned from visible to near infrared. The plasmonic properties are strongly dependent on their dielectric environments and thereafter can be easily varied by the dielectric change brought by the transition between bleached and colored states of electrochromic polymer. The introduction of plasmonic nanoparticles is expected to largely improve the color contrast of electrochromic polymer under different states and therefore avoid its possible electrochemical deterioration. This study will further our understanding on electrochromic polymer-induced plasmonic switching behaviors of plasmonic nanoparticles. Smart-window devices fabricated from plasmonic nanoparticles/electrochromic polymer hybrid nanostructures are expected to have improved color-switching characteristics. The knowledge gained from this study will also be useful for designing many other plasmon-based optical devices for controlling and directing light for a wide range of areas such as information displays, anti-counterfeiting inks, and photothermal systems for cancer therapy.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.