Preparation of Stainless Steel Superhydrophobic Surface and Analysis of Hydrophobic Mechanism.

By analyzing the application conditions of hydrothermal oxidation equipment, we found that the corrosion resistance of stainless steel is crucial. It is necessary to prepare superhydrophobic surface to improve the corrosion resistance and find a cost-effective and environmentally friendly preparation method. Therefore, this paper proposes a method combining nanosecond laser and post-treatment, which uses nanosecond laser to etch microstructure and reduces the surface energy through diverse post-treatment methods to achieve hydrophobicity. The surface morphology characteristics were studied, the wettability of various post-treatment methods was compared, and the hydrophobic mechanism was analyzed. The results show that the groove width has a significant impact on the surface morphology. Superhydrophobic surface can be obtained immediately after heat treatment and fluorosilane modification, while natural storage requires more than one month. All of the post-treatment can obtain hydrophobicity by reducing the surface energy, but the chemical composition is distinct. The cost-effective composite process of laser and heat treatment plays a guiding role in future research on the preparation of stainless steel superhydrophobic surface and has broad prospects in the future in large-scale production and application.

H2O2 Self-Supplying and GSH-Depleting Nanocatalyst for Copper Metabolism-Based Synergistic Chemodynamic Therapy and Chemotherapy.

Chemodynamic therapy (CDT) that involves the use of Fenton catalysts to convert endogenous hydrogen peroxide (H2O2) to hydroxyl radicals (·OH) constitutes a promising strategy for cancer therapy; however, insufficient endogenous H2O2 and glutathione (GSH) overexpression render its efficiency unsatisfactory. Herein, we present an intelligent nanocatalyst that comprises copper peroxide nanodots and DOX-loaded mesoporous silica nanoparticles (MSNs) (DOX@MSN@CuO2) and can self-supply exogenous H2O2 and respond to specific tumor microenvironments (TME). Following endocytosis into tumor cells, DOX@MSN@CuO2 initially decomposes into Cu2+ and exogenous H2O2 in the weakly acidic TME. Subsequently, Cu2+ reacts with high GSH concentrations, thereby inducing GSH depletion and reducing Cu2+ to Cu+ Next, the generated Cu+ undergoes Fenton-like reactions with exogenous H2O2 to accelerate toxic ·OH production, which exhibits a rapid reaction rate and is responsible for tumor cell apoptosis, thereby enhancing CDT. Furthermore, the successful delivery of DOX from the MSNs achieves chemotherapy and CDT integration. Thus, this excellent strategy can resolve the problem of insufficient CDT efficacy due to limited H2O2 and GSH overexpression. Integrating H2O2 self-supply and GSH deletion enhances CDT, and DOX-induced chemotherapy endows DOX@MSN@CuO2 with effective tumor growth-inhibiting properties alongside minimal side effects in vivo.

Analysis of the degradation of m-cresol with Fe/AC in catalytic wet peroxide oxidation enhanced by swirl flow.

Catalytic wet peroxide oxidation (CWPO) enhanced by swirl flow (SF-CWPO) was developed for the first time to explore the degradation of m-cresol in 3%iron/activated carbon catalysed Fenton reaction. Under the conditions of catalyst dosage of 0.6 g/L, H2O2 dosage of 1.5 mL/L, pH = 6 and reaction time of 20 min, the degradation rate of m-cresol and total organic carbon in 100 mg/L m-cresol solution reaches 81.5% and 82%, respectively. The reaction speed in the SF-CWPO system with an independently designed cyclone reactor was two times faster than the traditional CWPO systems. In addition, via liquid chromatography-mass spectrometry analysis of the degradation product, the possible degradation pathway for m-cresol was proposed. The proposed SF-CWPO can potentially be an efficient and economical method to treat organic pollutants in wastewaters.

Synergetic electrocatalytic degradation of isophorone by active oxygen species generated in the gas diffusion electrode and PbO2 anode.

Significant efforts have been made to achieve efficient H2O2 generation via oxygen reduction reaction (ORR). Here, the acetylene black (AB)-based gas diffusion electrodes (GDEs) modified by PTFE were fabricated and applied in a closed autoclave for H2O2 generation for the first time. The surface morphology, BET, XPS, cyclic voltammetry curves and linear scanning voltammetry curves of GDEs were all characterized. Additionally, the H2O2 generation experiments of GDEs and the relationship between H2O2 yield and BET surface area (SBET), double layer capacitance (Cdl) were all investigated. It could be found that the SBET and Cdl of GDEs kept a good linear relationship with H2O2 content, and 2#GDE (AB:PTFE = 1:3) possessed the optimal H2O2 generation capacity. Also, the effect of oxygen pressure and current density on H2O2 production was evaluated detailedly, indicating higher oxygen pressure was beneficial to the H2O2 generation and the preferable current density was 20 mA cm-2 due to the side reactions. And all the H2O2 electro-generation experiments exhibited a higher oxygen utilization efficiency (0.77%-2.93%). Finally, the efficient and synergetic electro-catalytic degradation of isophorone was achieved by self-made PbO2 anode and GDE.