Solar evaporation enhancement using floating light-absorbing magnetic particles

Abstract

We have demonstrated a new strategy for enhancing solar evaporation by using floating light-absorbing materials. Floating Fe 3O 4/C magnetic particles with an average size of 500 nm were synthesized by carbonization of poly(furfuryl alcohol) (PFA) incorporated with Fe 3O 4 nanoparticles. The Fe 3O 4/C particles had a BET surface area of 429 m 2 g -1, and a density of 1.44 g cm -3. Because of their hydrophobicity and a bulk packing density of 0.53 g cm -3, Fe 3O 4/C particles were floatable on water. Our results indicated that these Fe 3O 4/C particles enhanced the water evaporation rate by as much as a factor of 2.3 in the solar evaporation of 3.5% salt water. In addition, Fe 3O 4/C particles were easily recycled using a magnet, and stable after being recycled three times. Our work provides a low-cost and highly effective way for accelerating solar evaporation for industrial applications such as solar desalination, salt production, brine management and wastewater treatment. © 2011 The Royal Society of Chemistry.