多壁碳纳米管负载银/微晶纤维素定型复合相变材料的制备及性能研究

Preparation and Properties of Silver-loaded Multi-walled Carbon Nanotube/Microcrystalline Cellulose Stereotyped Composite Phase Change Materials

利用相变材料储存热能是提高传统能源利用效率与开发各种新能源的有效方法。固-液相变储能材料具有成本低、凝固点调节范围宽和相变焓值大等优势,成为相变材料中应用极为广泛的相变材料之一。然而,由于相变材料在使用过程中会出现低导热率和泄漏问题,在极大程度上限制了相变材料的实际应用。为了解决以上问题,本工作将负载银纳米粒子的氧化碳纳米管(O-MWCNTs)引入到微晶纤维素(MCC)基体中制备了微晶纤维素/多壁碳纳米管负载银(MCC/Ag-MWCNTs)三维多孔骨架,利用MCC/Ag-MWCNTs复合骨架吸附棕榈酸(PA)得到了MCC/Ag-MWCNTs/PA(Ag-PMCT)复合相变材料。O-MWCNTs上丰富的银纳米粒子在碳纳米管上形成微“桥梁”,从而构筑完整的导热路径,进一步提高复合相变材料的储热性能。同时,MCC/Ag-MWCNTs复合三维骨架展示出良好的封装效果和形状稳定性。本工作所制备的Ag-PMCT复合相变材料在建筑节能领域和电子器件热管理方面具有潜在应用,同时为碳基材料和金属粒子共同增强相变材料的导热性提供了一种新的思路。

The use of phase change materials to store thermal energy is an effective way to improve the efficiency of traditional energy utilization and develop various new energy sources.Solid-liquid phase change energy storage materials have the advantages of low cost,wide range of solidification point adjustment and large enthalpy of phase change,which make them become one of the most widely used phase change materials among phase change materials.However,the low thermal conductivity and leakage problems occur during the use of phase change materials,which greatly limit the practical application of phase change materials.To solve the above problems,oxidized carbon nanotubes(O-MWCNTs)loaded with silver nanoparticles were introduced into a microcrystalline cellulose(MCC)matrix to prepare a three-dimensional porous skeleton of microcrystalline cellulose/multi-walled carbon nanotubes loaded with silver(MCC/Ag-MWCNTs)in this work,and the MCC/Ag-MWCNTs/PA(Ag-PMCT)composite phase change material was obtained by adsorbing palmitic acid(PA)on the MCC/Ag-MWCNTs composite framework,abundant silver nanoparticles on O-MWCNTs form micro‘bridges’on carbon nanotubes,thus constructing a complete thermal conduction path,which further improved the thermal storage performance of the composite phase change material.At the same time,the MCC/Ag-MWCNTs composite 3D skeleton exhibits good encapsulation effect and shape stability.The Ag-PMCT composite phase change materials prepared in this paper have potential applications in the field of energy saving in buildings and thermal management of electronic devices,and provide a new idea for the enhancement of thermal conductivity of phase change materials by carbon based materials and metal particles together.