全椅式边含薁缺陷石墨烯纳米片的二阶非线性光学性质

基于全椅式边石墨烯纳米片(GNSs), 在保证GNSs化学稳定性的前提下并考虑了纳米片形状(六边形、 三角形和平行四边形), 在全椅式边GNSs中分别引入2, 3和4个薁构成的常见本征缺陷来调节这些GNSs的二阶非线性光学性质. 研究结果表明, 薁缺陷数量对于这些GNSs的二阶非线性光学响应起主导作用. 含有4个薁缺陷的GNSs具有较大的二阶非线性光学响应, 其中AP-4a纳米片具有最大的静态第一超极化率(<β₀>,230387.70 a. u., 平均每个重原子的<β₀>为2260.42 a. u.). 纳米片形状对体系的二阶非线性光学响应也有一定的影响. 薁单元片段在GNSs中不仅诱导GNSs发生电荷分布极化, 而且还在对非线性光学响应起重要贡献的主要电子跃迁中起主要作用. 薁单元作为碳基纳米材料的功能单元极大改善了其光电性质.

The Second Order Nonlinear Optical Properties of Azulene-defect Graphene Nanosheets with Full Armchair Edge

Based on the graphene nanosheets（GNSs） with full armchair edge， the second order nonlinear optical properties of these GNSs in different shapes with good chemical stability were modulated by introducing two， three and four azulenes. The result shows that the number of azulene defects plays a dominant role in the second order nonlinear optical responses of these GNSs. The GNSs with four azulenes have large second order nonlinear optical responses， among which AP-4a has the largest static first hyperpolarizability（<β₀>， 230387.70 a. u.， 2260.42 a. u. per heavy atom）. In addition， the nanosheet shape also has a certain effect. The azulene moieties not only induce charge distribution polarization of GNSs， but also dominate in the major electron transitions with important contribution to the nonlinear optical responses. Azulene as a functional unit of carbon-based nanomaterials significantly improves the photoelectric properties of carbon-based nanomaterials， and this finding provides practical strategies and useful information for future carbon-based nonlinear optical materials design.