Zhu Xinbei, Liu Jingkai, Zhang Liyue, Zhao Weiwei, Cao Yiyu, Liu Xiaoqing
Key Laboratory of Advanced Marine Materials, Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), Ningbo, 315201, P. R. China.
University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Small. 2024 Nov;20(48):e2405694. doi: 10.1002/smll.202405694. Epub 2024 Sep 9.
Solar thermal collectors based on phase change materials (PCMs) are important to promote the civilian use of sustainable energy. However, simultaneously achieving high photothermal efficiency and rapid heat transfer of the PCM carrier typically involves a high proportion of functional materials, contradicting a satisfying energy storage density. In this work, a surface-engineered anisotropic MXene-based aerogel (LMXA) integrated with myristic acid (MA) to produce phase change composites (LMXA-MA) is reported, in which the laser-treated surface composed of the hierarchically-structured TiO/carbon composites act as a light absorber to improve solar absorption (96.0%), while the vertical through-hole structure allows for fast thermal energy transportation from surface to the whole. As a result, LMXA-MA exhibits outstanding thermal energy storage (192.4 J·g) and high photothermal conversion efficiency (93.5%). Meanwhile, benefiting from the intrinsic low emissivity of MXene material, thermal radiation loss can be effectively suppressed by simply flipping LMXA-MA, enabling a long-term temperature control ability (605 s·g). The excellent heat storage property and switchable dual-mode also endow it with an infrared stealth function, which maintains camouflage for more than 240 s. This work provides a prospective solution for optimizing photothermal conversion efficiency and long-term thermal energy preservation from surface engineering and structural design.
基于相变材料（PCM）的太阳能集热器对于推动可持续能源的民用至关重要。然而，要同时实现PCM载体的高光热效率和快速传热，通常需要高比例的功能材料，这与令人满意的储能密度相矛盾。在这项工作中，报道了一种表面工程化的基于MXene的各向异性气凝胶（LMXA）与肉豆蔻酸（MA）集成以制备相变复合材料（LMXA-MA），其中由分层结构的TiO/碳复合材料组成的激光处理表面充当光吸收剂以提高太阳能吸收率（96.0%），而垂直通孔结构允许热能从表面快速传输到整体。结果，LMXA-MA表现出出色的热能存储（192.4 J·g）和高光热转换效率（93.5%）。同时，受益于MXene材料固有的低发射率，通过简单翻转LMXA-MA可以有效抑制热辐射损失，实现长期温度控制能力（605 s·g）。优异的储热性能和可切换的双模式还赋予其红外隐身功能，可保持伪装超过240 s。这项工作从表面工程和结构设计方面为优化光热转换效率和长期热能保存提供了一个前瞻性的解决方案。
