J. Mater. Sci. Technol. ›› 2024, Vol. 193: 81-89.DOI: 10.1016/j.jmst.2024.01.023

• Research Article • Previous Articles     Next Articles

Micronleaf-shape graphene interfaces on wood transverse sections as advanced photothermal evaporators for water purification

Zhaoyang Yua, Jinbo Hua,b,c,*, Gonggang Liua,c,*, Yuan Liua, Shanshan Changa,*, Denis Rodrigued, XiaodongWange   

  1. aCollege of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
    bHunan Taohuajiang Bamboo Science & Technology Co. Ltd., Yiyang 413400, China
    cAstrum Innovations Limited, Wisdom Park, Country Garden, Changsha 410006, China
    dDepartment of Chemical Engineering, Laval University, Quebec G1V 0A6, Canada
    eDepartment of Wood and Forest Sciences, Laval University, Quebec G1V 0A6, Canada
  • Received:2023-07-25 Revised:2023-11-22 Accepted:2024-01-03 Published:2024-09-10 Online:2024-09-05
  • Contact: *College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China. E-mail addresses: hjb1999@hotmail.com (J. Hu), liugonggang@csuft.edu.cn (G. Liu), changelxy@hotmail.com (S. Chang).

Abstract: Similar to transpiration, the formulation of interfacial solar evaporation has been designed to perform water treatment. The concept involves wood-based support (tree) with a graphene-based layer acting as leaves. To enhance light absorption and solar-thermal conversion capacity, a novel holly-leaf graphene (HLG) layer with an individual hollowed-out structure was engineered. The formation mechanism of this HLG was shown to be linked to the strong capillarity forces in the polyporous wood. By creating biomimetic leaves made of graphene, the light-to-heat conversion performance can be improved, while exhibiting substantially lower thermal conductivity (0.074 W/(m K)) than natural wood. Under solar irradiation, HLG/wood exhibits an outstanding evaporation rate of 1.96 kg/(m2 h), with an impressive efficiency of 94.2 %. A theoretical model of HLG/wood based on the thermal management capability was built to further confirm its structural superiority in facilitating photothermal conversion. Consequently, a bilayer evaporator based on HLG/wood has the potential to revolutionize water purification processes, including desalination of seawater, removal of heavy metal ions, and treatment of organic dye-contaminated wastewater.

Key words: Graphene, Wood cross section, Capillarity, Solar radiation, Transpiration