Poly(vinyl alcohol)/graphene oxide nanocomposite hydrogel with catalytic activity: the removal behavior and dual adsorption/catalytic degradation mechanism for dye wastewater

Abstract

The treatment of dye wastewater with traditional adsorption materials usually proceeds slowly with low removal efficiency and without completely eliminating dye molecules, leading to secondary pollution. In this work, poly(vinyl alcohol)/graphene oxide@tetraamino iron phthalocyanine (PVA/GO@TAFePc) nanocomposite hydrogels with catalytic activity were prepared via an in situ crosslinking method. Through interfacial covalent and π–π interactions, TAFePc was loaded onto GO layers with a high loading ratio, and GO@TAFePc was exfoliated and uniformly dispersed in the matrix. With increasing GO@TAFePc hybrid content, the pore size increased and a loose network structure was formed for the hydrogels, while the specific surface area rose significantly by using the hydrogel in a dye removal process, the removal rate of methylene blue (MB) increased sharply with contact time, reaching 98% in the presence of H2O2 with good reusability, and high removal efficiency was achieved for different dyes. The large surface area of the hydrogel was beneficial for MB adsorption. Meanwhile, under catalysis of TAFePc, a large amount of high activity ·OH was produced by H2O2 so as to degrade the MB molecules rapidly. Therefore, the MB degradation process for the composite hydrogel was ascribed to a dual adsorption/catalytic degradation mechanism. © 2020 Society of Industrial Chemistry

An Eco‐Friendly Polyvinyl Alcohol/Graphene Oxide‐Based Hydrogel as a Methylene Blue Adsorbent

“…In addition, the surface area of PVA/GO hydrogel was 31.616 m 2 g −1 , which was higher than 8.163 m 2 g −1 reported by Yu et al. [48] . The surface area of PVA/GO/aloe vera hydrogel was meaningfully lower than the PVA/GO hydrogel, about 10 % of the parental composite, with lower pore volume.…”

“…[47] In addition, the surface area of PVA/GO hydrogel was 31.616 m 2 g À 1 , which was higher than 8.163 m 2 g À 1 reported by Yu et al. [48] The surface area of PVA/GO/aloe vera hydrogel was meaningfully lower than the PVA/GO hydrogel, about 10 % of the parental composite, with lower pore volume. However, according to the UV/Vis adsorption analysis, the acceleration of MB adsorption was higher in PVA/GO/aloe vera hydrogel, indicating the more effective role of functional groups compared to the surface area of the hydrogel containing aloe vera.…”

Construction and Ion Transport-Related Applications of the Hydrogel-Based Membrane with 3D Nanochannels

“…Yu et al regulated the content of GO@TAFePc in PVA/GO@TAFePc hydrogels and obtained gel structures with different pore sizes and porosity. The removal rate of methylene blue was up to 98% [ 87 ]. Several studies have shown that adding metal oxides can effectively improve the dye removal rate.…”

Fabrication of Multiresponsive Magnetic Nanocomposite Double‐Network Hydrogels for Controlled Release Applications

“…Nanocomposite hydrogel (NC hydrogel), nanomaterials are incorporated in the cross‐linked polymeric chains, is one type of emerging hydrogels to present unique properties compared to traditional polymeric hydrogel. [ 1–4 ] NC hydrogels with different nanomaterials (e.g., carbon‐based nanomaterials, [ 5–8 ] polymer nanoparticles, [ 9 ] inorganic/ceramic nanoparticles, [ 10–12 ] or metal/metal oxide nanoparticles [ 13–15 ] ) present improved mechanical toughness [ 16,17 ] as well as novel performances (e.g., magnetic responsiveness, [ 13,18 ] near‐infrared responsiveness, [ 19–22 ] antimicrobial properties, [ 23,24 ] electricity, [ 25 ] thermal conductivity, [ 26 ] and fluorescence [ 27,28 ] ) for specific applications. Those “smart hydrogels” that respond to internal and external stimuli (e.g., light, [ 29,30 ] pH, [ 31–33 ] temperature, [ 34,35 ] or magnetic field [ 36,37 ] ) have been widely used in tissue engineering, [ 38,39 ] biosensors, [ 40,41 ] and drug delivery.…”