二维有机单晶的多模态物性研究

Multimodal Property Study of Two-Dimensional Organic Single Crystals

摘要: 本研究采用微间距生长法制备了高质量二维2,6-二苯基蒽有机单晶，系统研究了其结构特征、激子动力学与光电协同效应。表征结果显示2,6-二苯基蒽晶体具有7.542 Å和6.402 Å的晶格间距，展现出2.56 eV的宽带隙特性和窄半高宽的发射峰。偏振分辨荧光光谱揭示出其高达2.02的二向色性比，证实了强各向异性发光特性。变温研究表明，激子发射峰呈现39.96 meV蓝移且半高宽窄化67.50%，证实了低温下激子–声子耦合减弱。通过微纳电极转移技术制备的晶体管展现出优异的开关特性和较低的关态电流，并用低频噪声分析揭示了低漏极电流区的沟道本征噪声主导机制。本研究不仅深化了对有机晶体激子行为的认识，为设计高性能光电子器件提供了重要的材料体系。

Abstract: This study used the microspacing in-air sublimation growth method to prepare high-quality two-dimensional 2,6-diphenylanthracene organic single crystals, and systematically investigated their structural characteristics, exciton dynamics, and optoelectronic synergistic effects. The characterization results show that the 2,6-diphenylanthracene crystal has lattice spacings of 7.542 Å and 6.402 Å, exhibiting a wide bandgap characteristic of 2.56 eV and a narrow half width emission peak. Polarization-dependent fluorescence spectrum revealed a dichroic ratio of up to 2.02, confirming strong anisotropic luminescence properties. Temperature dependent studies have shown that the exciton emission peak exhibits a blue shift of 39.96 meV and a half width reduction of 67.50%, confirming the weakening of exciton phonon coupling at low temperatures. Moreover, the transistor prepared by micro nano electrode transfer technology exhibits excellent switching characteristics and lower off state current, and low-frequency noise analysis reveals the dominant mechanism of channel intrinsic noise in the low drain current region. This study not only deepens the understanding of exciton behavior in organic crystals, but also provides an important material system for designing high-performance optoelectronic devices.