Chouxuan Wang, Zhongguo Zhao*, Shengtai Zhou, Lei Wang*, Xinyue Liu, Rong Xue. Facile fabrication of densely packed ammoniated alumina/MXene/bacterial cellulose composite films for enhancing thermal conductivity and photothermal conversion performance. Journal of Materials Science & Technology, 2024, DOI: 10.1016/j.jmst.2024.06.024. 2023IF= 11.2.（1区材料科学类Top期刊）.
https://www.sciencedirect.com/science/article/pii/S1005030224006959
Abstract
The full arrival of 5 G and advances in electronic integration make efficient heat dissipation crucial for stable operation and longer product lifespan. In this study, a vacuum-assisted filtration process was employed to fabricate ammoniated alumina/MXene/bacterial cellulose (Al2O3-NH2/MXene/BC) composite films that display a unique integration of properties, encompassing ultra-high thermal conductivity (λ), mechanical flexibility, and high photothermal conversion performance. By leveraging the bridging effect among spherical Al2O3-NH2 and MXene nanosheets, a densely packed “point-surface” structure was constructed in BC by using a one-step preparation process. When the mass fraction of Al2O3-NH2/MXene (1:3, w/w) is 40 wt%, the O-BAl1M3 exhibited an in-plane λ of 20.02 W m-1K-1, which was 436 % and 94 % higher than that of pure BC and T-BAl1M3 (prepared by a two-step method), respectively. Furthermore, constructing an intact thermal conductive network within BC notably promoted photothermal and photoelectric conversion performance. The maximum surface temperature and voltage of the O-BAl1M3 film reached 106.9 °C and 48.34 mV when a sample with an area of 1.56 cm2 was exposed under a light intensity of 200 mW cm-2. By applying O-BAl1M3 film, the temperature inside a self-built greenhouse model reached up to 64.8 °C within 1200 s under a light intensity of 100 mW cm-2, which validated the practical application of the composite films and offered a novel approach for creating flexible films with superior photothermal conversion capability. This work provided insights into preparing functional composite films for efficient thermal management and photothermal conversion applications.