ABSTRACT
Fenton or Fenton-like technique, as one of the advanced oxidation processes, plays a significant role in the removal of non-easily degradable organic pollutants; however, most of such catalysts are fragile with poor structural integrity under large deformation, thereby restricting their wide applications. Herein, soft copper ferrite nanostructures functionalized silica nanofibrous membranes (CuFe2O4@SNM) were fabricated through a novel strategy with the combination of in-situ dopamine polymerization, ion adsorption, and cohesive precipitation method. Benefiting from the high metallic ion adsorption capacity of polydopamine together with the rapid co-precipitation of adsorbed ions on fiber surface in alkaline solution, the membranes possessed homogenously distributed nanostructured CuFe2O4, large specific surface area, and high pore volume, which are a benefit for the improvement of Fenton-like catalytic activity towards organic pollutants decomposition. The resultant soft CuFe2O4@SNM provided favorable catalytic performance towards organic pollutants with a relatively high degradation degree of 96% in 20â¯min, a fast removal rate of 0.148â¯min-1, and outstanding recyclability. The successful preparation of such fascinating ceramic nanofibrous membranes would provide a reference for further exploitation of new type Fenton or Fenton-like catalysts with outstanding softness towards wastewater purification.
ABSTRACT
The separation and purification of chemical molecules from organic media under harsh chemical environments are of vital importance in the fields of water treatment, biomedical engineering, and organic recycling. Herein, we report the preparation of a flexible SiO2/SnO2 nanofibrous membrane (SiO2/SnO2 NFM) with high surface area and hierarchical porous structure by selecting poly(vinyl butyral) as pore-forming agent and embedding crystalline phase into amorphous matrix without using surfactant as sacrificial template. Benefiting from the uniform micropore size on the fibers and negatively charged properties, the membranes exhibit a precise selectivity toward molecules based on electrostatic interaction and size exclusion, which could separate organic molecule mixtures with the same electrostatic charges and different molecular sizes with a high efficiency of more than 97%. Furthermore, the highly tortuous open-porous structures and high porosity give rise to a high permeate flux of 288â¯000 L m-2 h-1. In addition, the membrane also displays excellent stability and can be reused for ten consecutive filtration-regeneration cycles. The integration of high filtration efficiency, large permeate flux, good reutilization, and easy to industrialization provides the SiO2/SnO2 NFM for potential applications in practical molecular purification and separation science.
