等离激元共振金属纳米颗粒悬浮液太阳能光热转换机理与调控机制研究

The Surface Plasmon Resonance (SPR) effect has aroused general concern especially when it is applied on metal nanoparticles’ suspension to improve the efficiency of photo-thermal conversion. However, little is done on regulation of photo-thermal conversion characteristics of the metal nanoparticles’ suspension to fit perfectly with the distribution of solar energy. Therefore, it is necessary to carry out the study on optical properties regulation and photo-thermal conversion mechanism research of metal nanoparticles and its suspensions based on the Surface Plasmon Resonance (SPR) effect. The Ag@Au core-shell nanoparticles can be synthesized controllably by the seed mediated method. Parameters including the size and shape are adjusted to regulate the optical properties and related theoretical models are built up to predict the light response as the function of related factors. The instability and hydrodynamics of metal nanoparticles’ suspensions are discussed by establishing analysis models. The photo-thermal conversion efficiency of metal nanoparticles’ suspensions is studied experimentally and analyzed to find out the conversion rules and reveal the photo-thermal conversion mechanism. The direct absorption solar collector based on nanoparticles’ suspensions are applied in organic Rankine's circulation and industrial heat exchanger to efficient utilization as mid-and-low temperature thermal energy. It is significant to promote the application of metal nanoparticles and its suspensions to solar energy conversion, and other photo-thermal conversion areas.

等离激元金属纳米颗粒悬浮液具有较高的光热转换效率，开始受到研究者的广泛关注。然而，如何有效调控令其吸收光谱与太阳能能量分布相匹配及其调控机制尚待完善。因此，开展等离激元金属纳米颗粒悬浮液太阳能光热转换机理及调控机制的研究具有重要意义。本项目针对等离激元Ag@Au核壳纳米颗粒悬浮液，采用种子生长法调控颗粒的形貌和尺寸，建立金属纳米颗粒各参数与其悬浮液光学特性间的理论关系模型，考察金属纳米颗粒悬浮液的稳定性与流动特性，建立稳定性评价理论模型，通过控制金属纳米颗粒各参数来调控其悬浮液光热转换性能，通过实验方法研究金属纳米颗粒的光热转换效率，分析影响其光热转换效率的相关因素，揭示金属纳米颗粒及其悬浮液太阳能光热转换规律，阐明其光热转换机理及调控机制，探索其在有机朗肯循环和工业换热器中的高效利用。本项目对于推动等离激元金属纳米颗粒悬浮液在太阳能能量输运及其它光热转换领域的应用奠定理论基础。

本项目围绕等离激元纳米颗粒及其分散液的光热转换特性开展了相关实验和数值模拟研究，分别开展了纳米颗粒制备、分散液稳定性及其光热转换机理研究工作。采用种子生长法、水热合成法等手段实现了Au、Ag等金属纳米颗粒、Ag@TiO2、Au@TiO2核壳结构纳米颗粒、刺猬状复合结构颗粒等多种等离激元纳米颗粒的可控制备，从而有效调控等离激元纳米颗粒的光谱吸收特性；建立了金属纳米颗粒各参数及其悬浮液光学特性间的评价理论模型，获得了等离激元纳米颗粒及其分散液的光热转换机理；考察了等离激元颗粒悬浮液在静止状态下的稳定性和在工作条件下的可重复性，表明了等离激元颗粒悬浮液的潜在应用价值；开展了基于等离激元纳米颗粒的太阳能直接集热和体吸收式产蒸汽性能研究，发展了基于等离激元纳米颗粒悬浮液的体吸收式太阳能集热产蒸汽水净化技术，为等离激元纳米颗粒悬浮液在中低温太阳能热利用领域的应用奠定理论基础。