Cao Hong, Li Shuang-Zhu, Yang Jie, Liu Zheng-Ying, Bai Lu, Yang Wei
College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China.
State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
ACS Appl Mater Interfaces. 2023 Dec 6;15(48):55723-55733. doi: 10.1021/acsami.3c12302. Epub 2023 Nov 22.
The distinctive thermal energy storage properties of phase change materials (PCMs) are critical for solving energy issues. However, their inherently low thermal conductivity and limited energy conversion capability impede their applications in advanced thermal energy harvesting and storage systems. Herein, we developed magnetic composite PCMs with enhanced thermal conductivity for anisotropic photothermal and magnetic-to-thermal energy conversions. The hierarchically interconnected ferroferric oxide-coated boron nitride/poly(vinyl alcohol) (BN@FeO/PVA) porous scaffolds were constructed by a unidirectional freeze-casting method to enhance the directional heat transfer capability of the composite PCMs with a through-plane thermal conductivity of 1.84 W m K at a BN@FeO loading of 25.4 wt %. The superparamagnetic FeO nanoparticles endow the composite PCMs with unique solar absorption and magnetic response properties, and the energy conversion efficiency can be regulated by controlling the orientation of the synthesized magnetic particles in the composite PCMs. As a consequence, the resulting composite PCMs exhibit superior photo/magnetic-to-thermal energy conversion efficiency along the direction of orientation of magnetic particles. These novel findings provide an instructive guide to yield composite PCMs for efficient energy conversion.
相变材料（PCMs）独特的热能存储特性对于解决能源问题至关重要。然而，其固有的低导热性和有限的能量转换能力阻碍了它们在先进热能收集和存储系统中的应用。在此，我们开发了具有增强导热性的磁性复合相变材料，用于各向异性光热和磁-热能量转换。通过单向冷冻铸造法构建了分层互连的氧化铁包覆氮化硼/聚乙烯醇（BN@FeO/PVA）多孔支架，以增强复合相变材料的定向传热能力，在BN@FeO负载量为25.4 wt%时，其面内热导率为1.84 W m⁻¹ K⁻¹。超顺磁性Fe₃O₄纳米颗粒赋予复合相变材料独特的太阳能吸收和磁响应特性，并且可以通过控制复合相变材料中合成磁性颗粒的取向来调节能量转换效率。因此，所得复合相变材料在磁性颗粒的取向方向上表现出优异的光/磁-热能量转换效率。这些新发现为制备用于高效能量转换的复合相变材料提供了指导性的方向。
