亲水性石墨烯@TiO_(2)@石蜡光热相变微胶囊的制备及性能  

Preparation and properties of hydrophilic graphene@TiO_(2)@paraffin photothermal phase change microcapsules

作　　者：程辉 赵梦雪 毋伟[1] CHENG Hui;ZHAO Mengxue;WU Wei(College of Chemical Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]北京化工大学化学工程学院,北京100029

出　　处：《中国粉体技术》2025年第1期35-45,共11页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:21676023。

摘　　要：【目的】解决光热相变材料(phase change materials,PCMs)在实际光热储存领域中存在易泄漏、导热以及光热转换效率低的问题。【方法】采用微胶囊法,氧化石墨液相剥离可膨石墨制备亲水性石墨烯;亲水性石墨烯与无机材料TiO_(2)复合作为壳层,以石蜡为核,制备复合相变微胶囊,系统研究微胶囊性能。【结果】亲水性石墨烯添加量(质量分数)为1%时,制备的微胶囊为形状规则的球形结构,泄漏率为6.90%,热导率为0.459 W(/m·K),熔融焓为84.58 J/g,结晶焓为91.26 J/g,微胶囊化效率为63.33%;在模拟光照10 min后,微胶囊的温度最高达到64.8℃,相比纯石蜡提升31.4℃。【结论】亲水性石墨烯的加入对复合PCMs的光热转换效率有显著提升,具有良好的光热转换及储存性能。Objective Among the organic phase change materials,paraffin has high thermal and chemical stability,and small volume change during phase transition,non-corrosive and low cost.However,paraffin wax has problems such as poor thermal conductivity and photothermal conversion performance as well as easy leakage during practical use.Phase change microcapsules have good application prospects in thermal management and photothermal conversion.Thermal conductivity and solar absorption efficiency of their shell materials have a significant impact on their application performance.Titanium dioxide(TiO_(2)),a semiconductor material,exhibits excellent thermal conductivity and high ultraviolet light absorption efficiency.However,it barely absorbs visible light.The addition of graphene can expand its light absorption range,improving the photothermal conversion efficiency of microcapsules.However,graphene lacks polar groups on its surface,making it difficult to combine with other materials.Although surface modification is commonly used to improve graphene’s surface energy,it often adversely affects the photothermal performance of the microcapsules.To address this,the study uses graphene oxide to exfoliate graphite and prepare hydrophilic graphene.This material retains excellent photothermal properties of graphene,while offering the polar functional groups of graphene oxide,allowing it to integrate effectively with TiO_(2).Methods Graphene oxide has both the excellent photothermal properties of graphene and the polar functional groups of graphene oxide,which are easy to combine well with TiO_(2).In this paper,hydrophilic graphene was prepared by liquidphase exfoliation of expandable graphite using graphene oxide as an additive.Preparation of microcapsules with paraffin as core and TiO_(2) as shell using titanium butoxide(TBT)hydrolysis in N,N-Dimethylformamide(DMF)solution.Then hydrophilic graphene was added,and hydrophilic graphene was compounded with TiO_(2) shell through hydrogen bonding,and paraffin wax was used as the core to

关 键 词：太阳能 相变材料 微胶囊 石墨烯 石蜡 

分 类 号：TQ02[化学工程] TB4[一般工业技术]