Synergistic effect of Fe3O4 nanoparticles and Au nanolayer in enhancement of interfacial solar steam generation

For the first time, we investigated the synergistic effect of Fe3O4 nanoparticles (NPs) and Au nanolayer in interfacial solar steam generation (ISSG) of well water. Herein, single-or double-layer photoabsorbers were prepared by coating poplar wood with different concentrations of Fe3O4 NPs and/or various thicknesses of Au nanolayer. The maximum evaporation efficiency for the single-layer photoabsorber composed of Fe3O4 was 80% under 3 sun (1 sun=1 kW m-2) illumination. The most efficient single-layer photoabsorber coated by Au nanolayer resulted in the evaporation efficiency of 83.2% under 3 sun. The double-layer photoabsorber of Fe3O4 over Au nanolayer (Fe3O4/Au) and Au layer over Fe3O4 (Au/Fe3O4) were prepared. The Fe3O4/Au reached the evaporation efficiency of 88.7% and the evaporation rate of 3.76 kg m- 2 h-1 under 3 sun due to the synergistic effects of surface plasmon effect in Au NPs as well as black color and visible light absorbing ability of Fe3O4 NPs.