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In this work, an anti-icing coating based on superhydrophilic polyzwitterion brushes is reported. Poly(sulfobetaine methacrylate) (PSBMA) brushes were synthesized by surface-initiated atom-transferred radical polymerization to create superhydrophilic films on silicon wafers. The thickness of the PSBMA brushes film increased linearly with the polymerization time, and the film remained superhydrophilic in a nonassociated state when the thickness was less than ∼100 nm. DSC and FTIR analyses revealed that PSBMA contains more nonfreezable bound water than typical polyelectrolytes such as poly(sodium styrenesulfonate) and poly(2-(methacryloyloxy)ethyltrimethylammonium chloride), leading to lower ice adhesion strength than the latter two. At −20 °C, the PSBMA brushes coating demonstrated low ice adhesion strength of 60 kPa, showing a significant reduction in ice adhesion by up to ∼75% compared to uncoated silicon wafer. The optimum PSBMA layer thickness for low ice adhesion was ∼100 nm. These findings suggest that polyzwitterions are excellent candidates for anti-icing coating application.

As persulfate (S2O82−) is being increasingly used as an alternative oxidizing agent, developing low-cost and eco-friendly catalysts for efficient S2O82−activation is potentially useful for the treatment of wastewater containing refractory organic pollutant. In this study, the degradative features and mechanisms of carbamazepine (CBZ) were systematically investigated in a novel FeS- S2O82−process under near-neutral conditions. The results exhibited that CBZ can be effectively eliminated by the FeS-S2O82−process and the optimal conditions were: 250 mg/L FeS, 0.5 mmol/L S2O82−, and pH = 6.0. The existence of Cl−(1 and 50 mmol/L) has little influence on the CBZ elimination, while both HCO3−and HPO42−(1 and 50 mmol/L) significantly suppressed the CBZ removal in the FeS-S2O82−process. CBZ could be degraded via a radical mechanism in the FeS-S2O82−process, the working radical species (i.e., SO4•−and •OH) were efficiently formed via the promoted decomposition of S2O82−by the surface Fe2+on the FeS and the dissolved ferrous ions in solution. Based on the identified oxidized products and Fukui index calculations, a possible degradation pathway of CBZ was speculated. More importantly, a two-stage oxidation mechanism of CBZ elimination was speculated in the FeS-S2O82−process, the activation of S2O82−by the surface-active Fe(II)of FeS dominated in the initial 5 min, while homogeneous oxidation reactions played more essential parts than others in the following reaction stage (5–60 min). Overall, this study demonstrated that the FeS-S2O82−process is capable of removing CBZ from water efficiently.