Carbonized wood supported Fe3O4 nanoparticles for efficient solar-driven interfacial evaporation

Magnetized wood (M–W) has been proposed to be used as an absorber in solar-driven interfacial evaporation. The M−W could gain an evaporation rate of 1.46 kg m −2  h −1 under the combined effect of sunlight and magnetic fields, which is 27 % higher than carbonized wood (C–W). To explore the mechanism, they were subjected to SEM, XPS, and water contact angle tests. It is revealing that M−W forms much more microchannels for steam diffusion. The M−W shows 97 % optical absorption within the whole wavelength, while the C–W is lower than 85 %, revealing the M−W can gather most of the solar radiation. Finally, the permeability coefficients of carbonized and magnetized woods are calculated by the CFD model. The permeability coefficient of the M−W is 20 % higher than the C–W, which can be attributed to Fe 3 O 4 nanoparticles disturbing the steam growth in the magnetic field, hence decreasing the thickness of the liquid film covering the bubbles and improving the solar evaporation rate.