类黑磷纳米材料的制备及其光电探测性能研究

As we know, two-dimensional (2D) black phosphorus (BP) suffers from ambient degradation, which restrains the development on the device applications, while black phosphorus analogues (BPA), such as tellurium, bismuthene, indium selenide and tin sulfide, etc., not only have a similar folded structure of black phosphorus, high carrier mobility and tunable bandgap energy band, but are superior to BP in the environmental stability, which provides the possibility to solve the practical application of BP nanomaterials-based devices. Combined with the more stable 2D BP under alkaline conditions, this project intends to study the effect of different pH values on the exfoliation results of BPA fabricated by a liquid phase exfoliation (LPE) method and its environmental stability. The photodetection test of BPA nanomaterials-based photodetectors in alkaline aqueous solution exhibits that the photodetection performance regularly changes with the type and concentration of electrolyte, the external voltage, the wavelength and intensity of light, accordingly. On basis of theoretical calculation, it is expected to figure out the mechanism of photodetection ability of BPA nanomaterials-based photodetectors. Through stability study of BPA nanomaterials-based photodetectors in alkaline solutions, it is supposed to make it clear that the environmental stability of BPA nanomaterials-based photodetectors can be significantly enhanced compared to those in the aqueous solutions. The prospective results of this project are believed to have important scientific and technical significances in the exploitation of novel photodetector materials and devices.

二维黑磷在环境中易降解极大地制约了其在器件中的应用，而类黑磷材料，如碲烯、铋烯、硒化铟和硫化亚锡等，既具有类似黑磷的褶皱结构、高的载流子迁移率和可调控带隙能带等特性，又在抗氧化等稳定性上又均优于黑磷，这为解决黑磷基纳米材料器件的实际运用问题提供了可能。结合碱性条件下二维黑磷更加稳定这一特点，本项目拟采用碱性氛围下液相剥离技术，研究不同pH值对类黑磷剥离效果以及其环境稳定性的影响；在碱性水溶液中对类黑磷基光电探测器进行光电探测测试，研究揭示其光电探测性能随电解质种类及浓度，外界电压以及光波长和光强度等的变化规律，并结合理论计算，阐明其具有光电探测能力的机理；通过其在碱性氛围中的稳定性研究，揭示类黑磷基光电探测器稳定性提高的机理。此项目研究成果将为开发新型光电探测材料与器件提供重要的科学和应用价值。

黑磷及类黑磷纳米拥有高载流子迁移率、 大的电流开光比以及独特的光学、电学、热学和力学面内各向异性等性质，在很多领域具有优异的应用前景。然而，针对目前黑磷本身的环境不稳定性、易氧化等问题，本项目提出碱性溶液条件下制备类黑磷纳米材料以及在碱性溶液中对类黑磷基光电探测器进行光电探测性能研究。通过对液相剥离过程中实验参数的调节，揭示类黑磷纳米材料的产量、形貌和稳定性能等随溶剂种类、溶液浓度、超声功率和时间以及离心转速和时间等的变化规律；通过对类黑磷基光电探测器的光电探测实验参数调节，揭示类黑磷基光电探测器的的光电探测响应性能和稳定性能随溶液种类和浓度、外界电压、入射光波长和强度等的变化规律；结合理论计算，阐明类黑磷基光电探测器的优异光电探测响应能力以及高稳定性能机理。因此，本研究具有两个方面的科学意义：一是为提供高效制备尺寸和层数可控、高稳定性类黑磷纳米材料的技术方案；二是实现大尺寸、大规模高环境稳定性类黑磷纳米材料器件提供基本的材料解决技术。