柔性半导体型单壁碳纳米管/二硫化钨纳米片复合热电材料的研究

With the increasing serious situation of energy crisis and environmental protection, thermoelectric power generation device, which is considered as a representative of the waste of energy recycling, has gradually became the hotspot in field of new energy materials, devolvement of the thermoelectric materials with high conversion efficiency has an important value for research and application. In this project, we propose to prepare a new kind of light-weight flexible thermoelectric composite materials by using one dimensional (1D) semiconducting single walled carbon nanotubes (semi-SWCNTs) and two dimensional (2D) few layer tungsten sulfide (WS2) nanosheets through constructing a three dimensional network structure with line surface intercalation, and the transport mechanism of the electrons and phonons at the interface of the 1D and 2D nanomaterials will be investigated. Combining the feature of ease to control the Fermi level of semi-SWCNTs, N-type of three component thermoelectric composite materials at the same material system will be acquired. With low dimensional and nanostructure engineering of the materials, optimizing of the thermoelectric properties by tuning the electron and phonon transport will be achieved. The light-weight flexible thermoelectric devices will be fabricated to achieve the application in the field of power supply for low power electronic equipment. This project could expand the existing flexible thermoelectric material system, deepen the knowledge of the interface thermoelectric transport mechanism between 1D and 2D nanomaterials, which has great research space and potential application value for further promoting the application of nanotechnology in the field of advanced energy materials.

在能源危机和环境保护形势日益严峻的背景下，热电发电器件作为废弃能量再循环利用的代表已经逐渐成为全球新能源材料领域研究的热点，开发具有高转换效率的热电材料具有重要的研究和应用价值。本项目旨在将一维的半导体型单壁碳纳米管与二维的小片径少层二硫化钨纳米片这两种先进纳米材料复合，构筑线面插层的三维网络结构，揭示一维与二维材料界面电子与声子的输运特点和规律，制备新型轻质柔性复合热电材料。结合半导体型单壁碳纳米管费米能级易于调控的特性，在同一材料体系制备三元N型复合热电材料。利用材料的低维化和纳米化，实现电子和声子输运特性的协同调控从而优化复合材料的热电性能。通过制备轻质柔性热电器件，以期实现在小功率电子设备电源供给领域的应用。该项目可拓展现有的柔性热电材料体系，深化人们对一维与二维纳米材料界面热电传输机理的认识，对进一步推动纳米科技在新材料能源领域的应用，具有巨大的研究空间和潜在的应用价值。

在当前世界范围内能源危机和环境保护形势日益严峻的背景下，热电材料逐渐成为全球新能源材料领域研究的热点，开发具有高效热电转换效率的新型热电材料具有重要的研究价值和广泛的应用前景。本项目首先发展了类金属型1T相二硫化钨纳米片的相控制备技术。在此基础上，将二维的二硫化钨纳米片与一维的单壁碳纳米管这两种低维纳米材料进行复合，并以纤维素纸作为柔性基底材料，通过构建线面插层且无序致密的三维网络结构，获得了轻质柔性的新型复合热电材料。同时，利用碳纳米管费米能级易于调控的特性，在制备了P型复合热电材料的基础上，通过化学掺杂的方式，在原位获得N型复合热电材料。本项目制备的二硫化钨/碳纳米管复合热电材料，充分利用了材料的低维化和复合化，通过电子和声子输运特性的协同调控，实现了电导率和塞贝克系数在一定比例范围内的同时增长。实验结果表明，当二硫化钨与碳纳米管的摩尔比为1:10时，常温下最佳电导率为318 S·cm-1，塞贝克系数值为43.2 μV·K-1，得到的功率因子可达61.70 μW·m-1K-2。本项目制备的纤维素纸基二硫化钨/碳纳米管复合热电材料，在保证具有高的热电转换效率的同时，保留了纤维素纸的柔韧性，可以有效解决材料工作受冷热冲击造成的应力问题。该技术路线制备工艺简单，可重复性强，生产成本低廉，对生产设备和生产条件要求低，易于推广和应用。同时，对进一步推动纳米科技在新材料能源领域的发展，具有巨大的研究空间和潜在的应用价值。