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Solar-driven evaporation as a sustainable water purification technology exhibits great potential in solving the global water crisis. In this paper, a novel solar evaporator was successfully prepared with the reduced graphene oxide (rGO) and silver (Ag) nanowires as photothermal conversion media which were loaded into the sodium alginate (SA) hydrogel. It was found that the evaporation rate of the prepared evaporator reached 2.02 kg m−2 h−1 and the solar energy efficiency was 91% under one sun irradiation intensity. Furthermore, this novel solar evaporator exhibited expectant evaporation performance in the treatment of seawater and heavy metal sewage with excellent ion removal ability, with the removal efficiency of various ions higher than 99.9%. The ion-crosslinked SA hydrogel contained in the evaporator ensured the rejection of multivalent ions based on the distribution of carboxylate anions, and the three-dimensional porous channel of the super-hydrophilic hydrogel provided the convenient path for the transport of water molecules and the escape of water vapor. The binary composition of rGO and silver nanowires enhanced the photothermal conversion and the thermal conductivity, which was beneficial to the stable supply of thermal energy for evaporation. The purpose of this paper is to provide reference for promoting the practical application of solar evaporation.

Direct determination of arsenic species in real samples is challenging due to their trace concentration and spectral interferences by coexisting ions. Herein, we proposed an ultrasound-assisted dispersive solid phase microextraction (DSPME) procedure for the analyses of the trace inorganic arsenic. The hydrothermally synthesized cadmium sulfide nanoparticles (CdS NPs) completely adsorbed both arsenic species within 20 s at the initial arsenic concentration of 100 µg L−1. The detection limit (3 S/m) of the proposed method was found to be 0.5 ± 0.2 and 0.8 ± 0.2 ng L−1 for As(III) and As(V), respectively. The accuracy of the method against the systematic and constant errors was confirmed by the analysis of the Standard Reference Material (SRM) (>95% recovery with

A novel thin-film nanocomposite (TFN) forward osmosis (FO) membrane was fabricated by loading bovine serum albumin (BSA)/gold nanoparticles (GNPs) on the surface of a cockscomb-like nylon supporting membrane. The influence of the embedded BSA/GNPs on surface morphology, surface roughness, surface charge, separation, and FO performance of the TFN-FO membrane was investigated. The water flux of the BSA/GNPs-modified FO membrane could be increased to 55.2 ± 5.4 LMH, and the Js/Jw value was substantially decreased to 0.034 g/L, indicating a high selectivity of the modified membrane. BSA/GNPs located between the top of the nylon supporting membrane and the bottom of the polyamide (PA) skin layer provided passage for water transport and increased the roughness of the PA layer, thus enhancing the effective area on which the osmotic pressure could act. In addition, BSA/GNPs located at the bottom surface of the nylon supporting membrane provided a nearly electroneutral surface in the solution and alleviated dilutive concentration polarization. In summary, choosing a nylon membrane with a special cockscomb-like surface structure as the supporting layer to load BSA/GNPs nanoparticles proved to be a creative and effective nano-modification method for fabricating high-performance TFN-FO membranes.