One-Step Electrochemically Prepared Bionic Hierarchical Nickel Black@Graphene Composite Membrane for Desalination by Solar–Thermal Energy Conversion
Dongmin Yue, Keyi Ma, Hao Zhang, De Sun, Lingyu Zu
Abstract
Ingenious microstructure construction and appropriate composition selection are effective strategies for achieving enhanced performance of photothermal materials. Herein, a broccoli-like hierarchical nickel black@graphene (Ni@Gr) membrane for solar-driven desalination was prepared by a one-step electrochemical method, which was carried out simultaneously with the electrochemical exfoliation of graphene and the co-deposition of Ni@Gr material. The bionic hierarchical structure and the chemical composition of the Ni@Gr membrane increased the sunlight absorption (90.36%) by the light-trapping effect and the introduction of graphene. The Ni@Gr membrane achieved high evaporation rates of 2.05 and 1.16 kg m –2 h –1 under simulated (1 sun) and outdoor sunlight conditions, respectively. The superhydrophilicity and the hierarchical structure of the Ni@Gr membrane jointly reduced the evaporation enthalpy (1343.6 kJ/kg), which was beneficial to break the theoretical limit of the evaporation rate (1.47 kg m –2 h –1 ). This work encourages the application of bionic metal–carbon composite photothermal materials in solar water evaporation.