具有多重限幅机制的纳米激光防护功能材料的设计和制备

Aside from their numerous civilian applications, lasers have evolved into numerous modern battlefield weapons. Some are designed to dazzle or permanently disable humans by blinding, while others are used to destroy optical sensors, missiles, and other targets. The need for passive laser protectors to protect human eyes and all optical sensors from intense laser beams is not limited to the military, but is rather growing societal problems that can only escalate. A burning question related to this issue is the design and preparation of the novel nonlinear and optically active materials required for practical optical limiting applications, which still represents a significant challenge. In this project, we would like to design and synthesize a series of novel nanoscale functional materials for laser protection, and to determine the relationship between their structural parameters and optical limiting response while seeking to optimally combine materials and devices. One material alone could not satisfy all requirements for laser protection. The assembly of different functional materials is a possible way to solve this problem. Our goal is to fabricate functional elements capable of performing advanced optoelectronic functions in optical limiting systems. To achieve simultaneous protection against both pulsed and continuous wave (cw) or quasi-cw lasers, broadband optical limiting chromophores need to be designed for multimechanistic function. This includes the following requirements: reverse saturable absorbing behavior at the high-energy end of the visible; two-photon or multiphoton absorption behavior at the low-energy end of the visible; and nonlinear scattering behavior in the visible near-infrared region. Future work will be focused on in-depth studies of solution and solid state systems to provide a detailed understanding of the factors affecting the optical limiting response.

随着高能量、高功率、短脉冲激光器的大量出现，激光辐射对于人类眼睛、常规仪器光学窗口、武器系统及卫星光电传感器等已构成日益严重的威胁。开发有效的激光保护器保护人眼和所有光学及光电传感器免受激光束导致的暂时性或永久性伤害的意义不仅限于军事上，也为逐渐增大的社会公共安全问题所关注。基于此，研发基于非线性光学原理的新型宽光谱激光防护（光限幅）功能材料已成为亟待解决的问题。任何具有单一光限幅机制的材料都不可能在整个可见光谱范围内实时抗击脉冲激光、连续或准连续激光的攻击。在多年从事有机/高分子非线性光学功能材料的合成和性能研究基础上，我们拟设计和合成一系列具有多种光限幅机制（反饱和吸收、双光子/多光子吸收、非线性折射、和非线性散射等）共存的新型纳米激光防护功能材料，探索材料的结构参数和光限幅响应之间的构效关系，以寻求材料和器件的最优化结合，为材料走向实际应用提供理论和实验技术支撑。

激光武器以其高速、重复打击、目标杀伤精准、破坏程度可控、抗电磁干扰以及操作成本经济等特点，在未来战争、反恐、安保、救援中具有独特而重要的战略、战术价值。在所有已知的激光防护手段中，基于非线性光学原理的激光防护材料被公认为最好的防护材料之一。在国家自然科学基金（编号：61378072）的资助下， 我们创新设计和制备了一系列基于石墨烯、二硫化钼纳米片、碳纳米管、黑磷、有机卤素钙钛矿、金属氧化物/金属纳米颗粒、聚电解质刷等的有机纳米光限幅功能材料。在这些材料中除了基于聚电解质刷的纳米材料表现出非常微弱的非线性光学性能外，其余的材料均在可见光区域和（或者）近红外区域表现出优良的激光防护能力。在532 nm 和 1064 nm 处获得的最大非线性吸收系数分别是1151 cm/GW 和699 cm/GW， 最小的限幅阈值分别达到 1.56 J.cm-1和 2.67 J.cm-1。一些重要的结果已经发表在Prog. Mater. Sci. (影响因子：31.14)、Chem. Commun. (影响因子：6.319)、Chem. Eur. J. (影响因子：5.317， Hot Paper, 封面文章)、J.Mater. Chem. C(影响因子：5.256)、Appl. Phys. Lett. (影响因子：3.411)、RSC Advances(影响因子：3.108)等学术期刊上。