Green synthesis and environmental applications of alginate/polyacrylamide/titanium dioxide composite hydrogel

Abstract

A multifunctional sodium alginate/polyacrylamide/titanium dioxide (SA/PAM/TiO2) double network composite hydrogel was successfully prepared by sunlight‐induced polymerization and ionic cross‐linking method and the relationship between its structure and properties was studied. During the polymerization process, TiO2 is used as an initiator to promote the polymerization and is homogeneously immobilized on the three‐dimensional double network hydrogel matrix as the active component of photo‐catalysis. The dual network structure and highly hydrophilic functional groups in the structure improves the adsorption capacities of the hydrogel and photocatalytic performance of the catalyst by avoiding the aggregation of TiO2. The influences of different factors, such as the amount of cross‐linker, monomer ratio, titanium dioxide content, and exposure time, on the swelling properties of the hydrogel during the reaction process were investigated. The effects of titanium dioxide content, pH value, and initial concentration of methyl orange solution on the adsorption properties and photocatalytic performance of the hydrogel were also examined. In addition, the environmental applications of the material as a reusable adsorbent and an effective photo‐catalyst for the treatment of dyes were explored. The hydrogel possesses excellent mechanical properties and stability and was recycled for 10 times without any significant decrease in photocatalytic efficiency.

Preparation of modified humic acid/TiO2/P(AA-co-AM) nanocomposite hydrogels with enhanced dye adsorption and photocatalysis

“…In this study, the conformational relationship between the microstructure and photocatalytic performance of composite hydrogels was explored based on our previous research work. 31–33 A reusable HA-C/TiO 2 /P (AA- co -AM) nanocomposite hydrogel was designed and synthesized. Due to the introduction of humic acid into the hydrogel matrix to enhance the adsorption capacity and the excellent photocatalytic performance of nano-TiO 2 , the composite hydrogel has high efficiency in dye adsorption and degradation.…”

Preparation and Photocatalytic Performance of Sodium Alginate/Polyacrylamide/Polypyrrole-TiO2 Nanocomposite Hydrogels

“…In this study, the unique properties of nano TiO 2 , PPy, and hydrogel were synergistically combined while drawing upon previous research methodologies and achievements [34,35]. A class of SA/PAM/PPy-TiO 2 nanocomposite hydrogels that exhibit visible light responsiveness, high photocatalytic efficiency, excellent adsorption performance, and facile recyclability was successfully designed and synthesized.…”

UV‐initiated preparation and absorption properties of pseudo‐polyrotaxane cyclodextrin‐based PVA/poly (acrylamide‐co‐acrylic acid) hydrogel

“…The current treatments of the dye contaminated wastewater involve physical and chemical methods 4–6 . Among them, physical methods mainly include dye absorption in wastewater solution 7 and membrane filtration, 8 whereas the chemical methods generally degrade dyes in wastewater with the help of various materials, 9 electrolysis, 10 oxidation techniques 11 and photocatalytic approaches 12–15 . Compared to the chemical treatments, the physical methods are relatively simple, with the possibly to recycle and reuse the absorbed dyes by desorption of the material via certain techniques, thus reducing the overall production cost.…”