综合测量微纳米线材热物性、电物性和热电转换性能高集成仪器装置的研制

As a typical nanomaterial, nanoscale filamentary material has wide applications. The properties of nanoscale filamentary material are significantly different from bulk, and the measurement method for bulk materials even cannot be applied on nanoscale filamentary material. And hence, development of the precise measurement method for nanoscale filamentary material is becoming the frontier research and has been attracting intense interest. The project aims at the development of an innovative and highly integrated instrument for comprehensively measuring the thermophysical, electrical and thermoelectric properties of micro/nanoscale filamentary material from 2.8 K to 500 K, including thermal conductivity, thermal diffusivity, heat capacity, electrical conductivity, and Seebeck coefficient. The AC-DC measurement principle will be proposed and the corresponding innovative measurement methods will be developed, including the sample suspending/one dimensional steady state method, the T type method, the 3omega-T type method and the AC heating - DC detecting T type method. The principle of virtual lock-in amplifier will be proposed and the corresponding system will be developed on the LabVIEW platform. A high vacuum constant temperature system (2.8 K-500 K) will be built. An instrument control and data acquisition system will be developed to integrate the above-mentioned methods and systems. Finally a highly-integrated instrument for micro/nanoscale filamentary material thermophysical, electrical and thermoelectric properties comprehensive measurement from 2.8 K to 500 K will be developed, which is expected to fill the gaps in comprehensive measurement of the properties of nanoscale filamentary material.

纳米线材作为典型纳米材料具有广阔的应用前景，其性能与宏观材料显著不同且宏观尺度下的表征方法难以适用，开发精确测量纳米线材性能的方法成为国际前沿和热点之一。项目旨在开发具有原理创新的综合测量微纳米线材热物性、电物性和热电转换性能的高集成仪器装置，实现对微纳米线材热导率、热扩散率、比热、电导率和塞贝克系数在2.8-500K范围的精确综合测量。项目拟提出交-直流混合测量原理，开发和完善申请人发明的同时测量热导率和电导率的悬架一维稳态法，测量热导率、热扩散率、比热和吸热系数的T形法、3omega-T形法和测量塞贝克系数的交流加热-直流探测T形法；提出虚拟锁相概念，开发虚拟锁相测量系统；搭建2.8-500K高真空低温恒温系统，构建统一的仪器控制和数据采集系统将上述各方法和系统高度集成。研制一套2.8-500K综合测量微纳米线材热物性、电物性和热电转换性能的科学仪器，填补国际上在此研究领域的空白。

纳米线材作为典型纳米材料具有广阔的应用前景，其性能与宏观材料显著不同且宏观尺度下的表征方法难以适用，开发精确测量纳米线材性能的方法成为国际前沿和热点之一。项目提出了交-直流混合测量原理，开发和完善了申请人发明的同时测量热导率和电导率的悬架一维稳态法，测量热导率、热扩散率、比热和吸热系数的T形法、3omega-T形法和测量塞贝克系数的交流加热-直流探测T形法，发展了测量热导率和热电性质的H形法。提出了虚拟锁相概念，开发了虚拟锁相测量系统，克服了普通商用锁相放大器测量受动态存储限制和低频时（<0.1 Hz）测量时间过长和相位不稳定的缺陷；购置、搭建并校验了温控范围达到2.8 K-500 K的高真空恒温系统，保证温控精度达到0.1 K。使研制的仪器装置测量环境温度在2.8 K-500 K可调，真空度达到10-4 Pa。项目通过仪器原理开发、硬件配置、软件开发、误差分析、仪器标定和实际微、纳米尺度样品测试等系统研究，研制了一套具有原理性创新的综合测量微纳米线材热物性、电物性和热电转换性能的高集成仪器装置。该仪器可综合测量微纳米线材的电导率、电阻温度系数、热导率、热扩散率、吸热系数、比热、塞贝克系数和优值系数。测量了直径为25μm的铂(99.95%)和直径为80μm康铜(Constantan, 60% Cu 40% Ni) 的物性参数，和已有文献结果比较，校验了该仪器装置的测量精度，并开展了详细的误差分析，分析结果表明仪器的测量不确定度可达到预定的各项指标。在研制的仪器装置上，项目开展了实际微、纳米尺度样品的热物性、电物性和热电转换性能研究与测试：综合研究了微米量级石墨烯纤维、钯基非晶合金丝、碳化硅纤维和有机热电纤维的热物性、电物性和热电转换性能；积累了各材料在不同温度的物性数据，研究了物性随温度及微观结构等的变化规律和物理机制。综合表征了单根多壁碳纳米管，硫化镉纳米线和单层石墨烯条带的热物性、电物性和热电转换性能等。原位表征了受聚焦离子束辐照石墨烯条带的热物性，并首次在二维材料石墨烯中实验实现了高达26%的热整流。项目开发的综合测量微纳米线材热物性、电物性和热电转换性能的高集成仪器装置具有原理创新，填补了国际上在此研究领域的空白。