A Sandwich Structure Ag/MgFe2O4-Deposited Surface Carbonized Wood for Integrated Solar Steam Generation and Photoreduction of Cr(VI)

The severe deterioration of the marine ecosystem significantly negatively impacts the performance of solar-driven steam generation (SSG) and the quality of the obtained freshwater. Herein, a bifunctional Ag/MgFe 2 O 4 @SCW reactor with a sandwich structure is designed for efficient SSG and Cr(VI) reduction, which is constructed via in situ deposit Ag nanoparticles (NPs) and MgFe 2 O 4 onto surface carbonized wood (SCW). Owing to the advanced sandwich structure and strong interfacial interactions between each component, an ultra-high evaporation rate of 1.55 kg m −2 h −1 and the efficiency of 88.6% are achieved using Ag/MgFe 2 O 4 @SCW under 1 sun. The system exhibits the long-term evaporation performance in the simulated sewage and strong acid/base solutions along with water-harvesting capacity in outdoor solar desalination. The quality of distilled water after desalination of actual seawater and NaCl solutions with different concentrations meets the WHO-recommended drinkable water standards. Furthermore, Ag/MgFe 2 O 4 @SCW shows outstanding antibacterial property, self-desalting capacity, as well as reusability and structure stability. Most importantly, the fast carrier separation endows Ag/MgFe 2 O 4 @SCW with superior photocatalytic activity and Cr(VI) photoreduction of up to 96.1% after 180 min of illumination. The bifunctional Ag/MgFe 2 O 4 @SCW reactor provides an advanced synergistic mechanism for improving SSG and photocatalytic performance, while being promising for solar-powered production of clean water.