1,3-二苯基-2-吡唑啉纳米带的制备及其光波导性质

以1,3-二苯基-2-吡唑啉(DP)为目标化合物, 利用再沉淀方法, 以混合溶剂作为不良溶剂, 制备了形貌均一、宽度约2 μm、厚度200 nm和长度数十微米的一维纳米带状结构. 选区电子衍射结果证实, DP分子在纳米带中因为强的分子间π-π相互作用而沿着晶体[100]方向优势生长. 稳态光谱结果表明, DP纳米带具有不同于分子和体相材料的介观特性. 由于J-聚体在DP纳米带中优势形成, 其480 nm的发射峰与分子和体相材料相比分别红移了30和20 nm. 利用扫描近场光学显微镜进一步发现, 一维DP纳米带类似于天然的亚波长尺度谐振腔, 紫外激发DP分子发射的荧光被限域在DP纳米带中, 沿一维方向传导并在两端耦合输出.

Optical Waveguide Based on Crystalline Organic Nanobelts of 1,3-Diphenyl-2-pyrazoline

1D single-crystalline 1,3-diphenyl-2-pyrazoline(DP) nanobelts were prepared by the modified repercipication method with mixed poor solvents. The thickness of DP belt can be controlled at 200 nm with the width at 2 μm and the length at tens of microns. XRD and SAED indicate that the DP nanobelt grow along the [100]direction due to the π-π stacking of DP molecule. The steady-state absorption and fluorescence spectra indicate that DP nanobelts have unique optical properties which are different from the monomers and the bulk crystals. Furthermore, we find the belts are able to absorb the excitation light and propagate the PL emission towards the tips. The results presented in this paper provide useful information for the design and fabrication of optical waveguides from molecular materials.