Co-Innovation Center of Efficient Processing and Utilization of Forest Resource, School of Materials Science and Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
Bioproducts Institute and Department of Chemical and Biological Engineering, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada.
Int J Biol Macromol. 2023 Jul 1;242(Pt 3):125018. doi: 10.1016/j.ijbiomac.2023.125018. Epub 2023 May 22.
Two-dimensional (2D) evaporation systems could significantly reduce the heat conduction loss compared with the photothermal conversion materials particles during the evaporation process. But the normal layer-by-layer self-assembly method of 2D evaporator would reduce the water transportation performance due to the highly compact channel structures. Herein, in our work, the 2D evaporator with cellulose nanofiber (CNF), TiCT (MXene) and polydopamine modified lignin (PL) by layer-by-layer self-assembly and freeze-drying methods. The addition of PL also enhanced the light absorption and photothermal conversion performance of the evaporator due to the strong conjugation and π-π molecular interactions. After the combination process of layer-by-layer self-assembly and freeze-drying process, the as-prepared freeze-dried CNF/MXene/PL (f-CMPL) aerogel film exhibited highly interconnected porous structure with promoted hydrophilicity (enhanced water transportation performance). Benefiting these favorable properties, the f-CMPL aerogel film showed enhanced light absorption performance (surface temperature could be reached to 39 °C under 1 sun irradiation) and higher evaporation rate (1.60 kg m h). This work opens new way to fabricate cellulose-based evaporator with highly evaporation performance for the solar steam generation and provides a new idea for improving the evaporation performance of 2D cellulose-based evaporator.
二维（2D）蒸发系统在蒸发过程中与光热转换材料颗粒相比，可显著降低热传导损失。但是，由于通道结构高度紧凑，二维蒸发器的常规逐层自组装方法会降低水传输性能。在此，在我们的工作中，通过层层自组装和冷冻干燥方法制备了纤维素纳米纤维（CNF）、TiCT（MXene）和由层状自组装和冷冻干燥过程组合而成的、用聚多巴胺改性木质素（PL）修饰的 2D 蒸发器。PL 的加入还增强了蒸发器的光吸收和光热转换性能，因为它具有强共轭和π-π分子相互作用。在层层自组装和冷冻干燥过程的组合之后，所制备的冷冻干燥 CNF/MXene/PL（f-CMPL）气凝胶薄膜具有高度互连的多孔结构，提高了亲水性（增强了水传输性能）。得益于这些有利的特性，f-CMPL 气凝胶薄膜表现出增强的光吸收性能（在 1 个太阳照射下，表面温度可达到 39°C）和更高的蒸发率（1.60 kg·m·h）。这项工作为太阳能蒸汽产生开辟了制造具有高蒸发性能的基于纤维素的蒸发器的新途径，并为提高基于 2D 纤维素的蒸发器的蒸发性能提供了新的思路。
