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Photocatalytic materials are often used in the field of electrolysis of water for its competitive performance and low cost. This study describes the use of TiO2 for providing free electrons to prepare hydrated negative air ions together with the Lenard effect caused by air–water collision. The lifetime of HNAIs increased by 47.62% in comparison with the traditional corona discharge method; both the stability and the actual yield of the HNAIs increased significantly. The stability of HNAIs has a correlative relationship with the molecular weight and relative humidity. Lower mobility of the HNAIs with larger molecular weight results in low probability of collision with other air particles, making it relatively stable. Water molecules could form a water shell around the cluster ions in a high relative humidity environment, which can protect the ions, avoiding physical collision to extend the lifetime.

Photocatalytic materials are often used in the field of electrolysis of water for its competitive performance and low cost. This study describes the use of TiO

A highly efficient Fenton-like catalyst was successfully developed by covalently immobilizing a Cu(II)–pyridine group complex onto silica microspheres. The catalyst was characterized by SEM, FTIR and XPS measurements. The catalytic activity was evaluated by heterogeneous degradation of Rhodamine B (RhB) with H2O2 in the dark. The effects of pH, catalyst loading, H2O2 concentration, initial dye concentration, and temperature on the degradation kinetics were investigated to optimize operational variables and find the potential mechanisms. It was found that the optimum pH of medium was near neutral, at which over 98% of RhB (5–7.5 mg L−1) was efficiently decolorized in 6 hours with 2 g L−1 catalyst and 200 mg L−1 H2O2. The TOC removal of RhB (10 mg L−1) also reached 72% after the reaction duration. Meanwhile, the acute toxicity of RhB to marine bacteria Vibrio fischeri was almost completely eliminated. The degradation of RhB could be well described with a pseudo-first order kinetic model. The reaction activation energy was approximately 38.60 kJ mol−1. Fluorescence analysis and free radical scavenging experiments were performed, and revealed that the hydroxyl radical was the main active species for RhB degradation. The stability of the catalyst was confirmed by insignificant leaching of copper species and loss of activity after four cycles. Based on these results and the literature, a possible mechanism for RhB degradation was proposed.

In this study, a bi-functionalized magnetic iron oxide composite which was covalently bound by ammonium and phosphonate groups has been employed as a novel sorbent for effective sorption of uranium(VI) from alkaline media. The maximum sorption capacity was observed at pH 9.0 with a capacity of 70.7 mg g−1 at CU(VI)initial = 21.7 mg L−1. The sorption isotherm followed a pseudo-second order kinetic equation and could be described by a Freundlich isotherm. The thermodynamics research showed that the sorption was a feasible and endothermic process. Since the as-prepared material could be separated by magnetic field without filtration and centrifugation, it could be a promising sorbent for highly-efficient removal of U(VI) from alkaline solution.