高级检索

    卟啉改性聚芴功能材料的制备及光电性能

    Preparation of Porphyrin-Modified Polyfluorene Functional Materials and Their Optoelectronic Properties

    • 摘要: 神经突触仿生在实现高效人工神经网络中至关重要,其中的关键是寻找到合适的材料。有机高分子材料可以通过设计结构来调节电学性能而备受关注。通过Suzuki偶联将金属卟啉和聚芴结合得到功能材料聚芴-锌卟啉聚合物(PF-ZnPor),该材料具有较好的热稳定性且可溶于极性溶剂。以PF-ZnPor为活性层,采用溶液旋涂法制备了结构为Al/PF-ZnPor/ITO的器件并应用于突触仿生研究,该器件成功模拟了突触的增强和抑制、记忆-遗忘-再记忆等类人脑学习行为。

       

      Abstract: Neural synapse mimicry plays a crucial role in realizing efficient artificial neural networks, and finding suitable materials for synapse mimicry devices is critical. Among many alternative materials, organic polymers can be designed with different structures to modulate the electrical properties, thus attracting the attention of researchers. The redox property of metal porphyrin and the charge transport property of polyfluorene were bonded to the same molecule by Suzuki coupling. Then the porphyrin-containing polyfluorene functional material (PF-ZnPor) was obtained, which had good thermal stability and was soluble in polar solvents. The structure of polymers was verified by X-ray photoelectron spectroscopy (XPS), UV-visible absorption spectroscopy and steady-state fluorescence spectroscopy, and thermogravimetric analysis of their stability. Using PF-ZnPor as the active layer, devices with the structure of Al/PF-ZnPor/ITO by solution spin-coating were prepared and applied to synapse mimicry research. The devices successfully simulated the synaptic enhancement and inhibition, the learning behavior of the human-like brain of remembering-forgetting-remembering, and so on. The effect of different thicknesses of the active layer on the device performance was also investigated. The results show that the electrical performance of the devices diminishes with increasing thickness of the active layer film. The HOMO energy level, LUMO energy level, and electrostatic potential (ESP) surface of the basic unit of PF-ZnPor were simulated by density-functional theory (DFT). The theoretical validation is in agreement with the actual experimental results. This study provides a new idea for the design of organic polymer resistive change materials applied to synaptic bionic devices.

       

    /

    返回文章
    返回