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p-Hydroxybenzoic acid is an emerging contaminant because it has multiple sources such as the hydrolysis of methylparaben, ethylparaben and propylparaben used widely as preservatives in food and drinks, and as well as from the agro-industrial wastewaters. In this study, the nano-ZIF-8@chitosan microspheres (ZIF-8@CSM) were fabricated via the combination of inverse emulsion method and in-situ growth method. The performance of ZIF-8@CSM for the adsorption of p-hydroxybenzoic acid from aqueous solution was studied. The adsorption kinetics showed that the adsorption rapidly reached the equilibrium about 30 s. The equilibrium data were well described by the Langmuir isothermal model and the estimated maximum adsorption capacity was 128.70 mg/g. The thermodynamics analysis indicated negative free energy, enthalpy, and entropy changes suggesting that the adsorption process was spontaneous and exothermic. ZIF-8@CSM is promising to be used as a good adsorption material to remove p-hydroxybenzoic acid rapidly from aqueous solutions.

Tough and transparent polyurethane networks with self-healing capability at mild temperature conditions were successfully prepared in a 1-pot procedure. The self-healing ability of synthesized polyurethane comes from the covalent disulfide metathesis and non-covalent H-bonding. The mechanical testing indicates that disulfide metathesis reforms the covalent bonds on a longer time scale, while H-bonding gives rise to a healing efficiency of around 46% in the early healing processing. The compromise between mechanical performance and healing capability is reached by tailoring the concentration of disulfide. The tensile strength of the sample with 100% self-heal efficiency can get to 5.01 MPa, which can be explained by higher mobility of polymer chain under ambient temperature from creep testing.

Ag loaded mesoporous silica-embedded TiO2 nanocomposites were successfully synthesized via two different routes, including one-pot solvothermal method and solvothermal-chemical reduction method, both using Titanium (IV) n-butoxide (Ti(OC4H9)4) as a precursor, formic acid as a solvent and reducing agent, silver nitrate as a silver source and tetraethyl silicate (TEOS) as a stabilizer. The transmission electron microscopic (TEM) images showed that silica-embedded anatase TiO2 sample exhibited approximately rhombic shape and Ag nanoparticles could be embedded into the nanocomposites or deposited on the surface with high dispersion. The N2 adsorption-desorption isotherms indicated that the silica-embedded anatase TiO2 had obvious mesoporous structure with a BET specific surface area of 203.5 m2·g-1. All Ag loaded silica-embedded TiO2 composites showed a higher photocatalytic H2-generation activity from water splitting under simulative solar light irradiation than that of TiO2 products. The maximum H2 production rate (6.10 mmol·h-1·g-1) was obtained over 2% Ag/silica-embedded TiO2 nanocomposites (2% Ag/MST) prepared by solvothermal-chemical reduction method, which was 20 times that achieved on the silica-embedded TiO2 sample. The enhanced photocatalytic H2-evolution activity of Ag loaded mesoporous silica-embedded TiO2 nanocomposites can be attributed to the multi-function of surface Ag co-catalyst, mesoporous structure, and embedding of silica.