Hierarchical 3D Reduced Graphene Porous-Carbon-Based PCMs for Superior Thermal Energy Storage Performance
Hierarchical 3D Reduced Graphene Porous-Carbon-Based PCMs for Superior Thermal Energy Storage Performance
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分层 3D 还原石墨烯多孔碳基 PCM 具有卓越的热能存储性能
DOI：
10.1021/acsami.8b09541
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发表时间：
2018
影响因子：
9.5
通讯作者：
Wang Ge
中科院分区：
文献类型：
--
作者：
Li Ang;Dong Chen;Dong Wenjun;Atinafu Dimberu G;Gao Hongyi;Chen Xiao;Wang Ge
相变焓和导热系数是定形相变材料在实际应用中的两个基本参数。本文中，通过碳化氧化石墨烯@金属有机骨架（GO@MOF）模板成功地合成了分级三维（3D）还原石墨烯多孔碳载体PCM，其同时实现了大的相变焓和高的热导率。在碳化过程中，MOF被转化为分层多孔碳，而GO被还原为高热性能还原石墨烯（rGO）。从而获得了具有高孔隙率和大比表面积的分级三维多孔炭结构，为包覆相变材料提供了合适的条件。此外，碳的孔隙通过毛细管力和表面张力稳定了相变材料。PCM分子与rGO之间的相互作用显著降低了界面热阻，使复合材料显示出高的热导率。此外，三维网络结构促进了硬脂酸分子在受限的孔隙空间中的拉伸和结晶特性，从而提高了热释放效率。与rGO/MOF-5-C载体相比，rGO@MOF-5-C的分级3D结构显示热导率为0.60 ± 0.02 W m-1 K-1，提高了27.7%，具有大的相变潜热168.7 J g-1，提高了18.5%。此外，所获得的ss-PCM具有瞬态热响应和良好的耐久性，表明其在热能储存应用中具有良好的潜力。
Phase change enthalpy and thermal conductivity are the two essential parameters for practical applications of shape-stabilized phase change materials (ss-PCMs). Herein, hierarchical three-dimensional (3D) reduced graphene porous carbon support PCMs have been successfully synthesized by carbonizing a graphene oxide@metal–organic framework (GO@MOF) template, which simultaneously realizes large phase change enthalpy and high thermal conductivity. During the carbonization process, MOFs were converted into hierarchical porous carbons, whereas GO was reduced to high-thermal-performance reduced graphene (rGO). Thus, a hierarchical 3D porous carbon structure with high porosity and large specific surface area was obtained, which provided a suitable condition for encapsulating PCMs. Furthermore, the pores of carbon stabilized the PCMs by capillary force and surface tension. The interaction between the PCM molecule and rGO significantly decreased the interfacial thermal resistance and made the composites reveal high thermal conductivity. Furthermore, the 3D network structure promoted the stretching and crystallization characteristics of the stearic acid molecule in the confined pore space, which enhanced the heat release efficiency. Compared with the rGO/MOF-5-C support, the hierarchical 3D structure of rGO@MOF-5-C revealed a thermal conductivity of 0.60 ± 0.02 W m–1K–1, which was 27.7% improvement, with large phase change latent heat of 168.7 J g–1, which increased by 18.5%. Additionally, the obtained ss-PCMs showed transient thermal response and good durability, indicating its promising potential in thermal energy storage application.