新型LaB6基等离激元纳米流体的太阳能光热转换机理及其调控研究

With the increasingly aggravation of energy crisis, improving the utilization efficiency of solar energy can effectively relive the global energy issue. The absorption and conversion of working fluid can be enhanced by plasmonic nanofluids based on metal nanostructures. However, their potential applications will be restricted since it is difficult to control their surface plasmon resonance frequencies ranging from the visible to near-infrared regions effectively. Therefore, developing the novel nanofluids based on plasmonic nanostructures with tunable surface plasmon resonance frequencies in the near-infrared regions have become challenges and opportunities for future solar technology. Novel plasmonic nanofluids based on LaB6 nanostructures with tunable surface plasmon resonance frequencies in the near-infrared regions are expected to be the ideal system for solar thermal conversion. In this research proposal, based on the controllable synthesis of LaB6 nanostructures, we aim to study solar thermal conversion mechanism of novel plasmonic nanofluids; to clarify surface plasmon resonance and surface plasmon response; to elucidate the effect of composition, size and morphology, surrounding dielectric environment of nanostructures on solar absorption; and then to realize effective regulation on solar thermal conversion of nanostructures based on LaB6. Ultimately, we hope to put forward the development of novel plasmonic nanofluids with high efficiency and controllable solar thermal conversion.

随着能源危机的日益加剧，提高太阳能的利用效率能够有效缓解全球能源危机。基于金属纳米颗粒的等离激元纳米流体能显著提高工质对太阳能的吸收和光热转换效率。但由于其可见光波段等离激元频率较难有效调控至近红外波段而制约其应用前景。因此，开发频率可调的新型等离激元纳米流体已成为新的挑战和机遇。基于近红外波段等离激元频率可调的LaB6纳米颗粒，构建新型等离激元纳米流体，有望成为太阳能光热转换的理想体系。本项目旨在基于LaB6纳米结构的可控制备，系统研究太阳辐射下新型等离激元纳米流体的光热转换微观机制，阐明等离激元共振效应和表面等离激元响应等，揭示材料组分、纳米结构的尺寸和形貌、周围介电环境等对光吸收辐射的影响，从而实现纳米结构的光热转换效率的有效调控。在此基础上开发光热转换效率高、可调控的新型等离激元纳米流体。

设计制备LaB6基纳米晶及其纳米流体对于研究局域表面等离共振（LSPR）增强太阳能光热转换的作用机制、开发新型近红外辐射响应的等离激元共振光热转换材料、实现太阳能全光谱吸收和高效光热转换具有重要的意义。本项目围绕等离激元材料及其纳米颗粒和纳米流体的制备和光热转换特性展开了相关的理论和实验研究，分别开展了材料光学性质的调控、纳米材料的可控制备、纳米流体稳定性及其光热转换机理研究工作。采用固相法通过优化合成实验参数实现了LaB6基纳米材料的可控制备，从而有效调控等离激元纳米流体的光谱吸收特性；拓展制备了YB6、CeB6及相关三元六硼化物等离激元纳米颗粒及其纳米流体；考察了等离激元纳米流体在静止状态下的稳定性，分析了纳米流体的超稳定分散机理；获得了等离激元纳米晶及其纳米流体的全光谱吸收和光热转换机理；表明了等离激元LaB6基纳米流体的潜在应用价值。本项目研究不仅揭示了LaB6基纳米晶LSPR性质提高太阳能的光吸收、增强光热转换效率的作用机理，更为重要的是提出了超细六硼化物等离激元纳米材料及其超稳定纳米流体的新思路与新方法，为等离激元纳米流体在中低温太阳能热利用领域的工业应用奠定了实验基础。