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Immobilization is considered as a promising strategy toward the practical applications of powdered adsorbent. Herein, three dimensional (3D) printing cylindrical capsules with cross-linked PVA hydrogels membrane in encapsulate Chlorella pyrenoidosa (Cp) were utilized for removal of lead ions. The chemical compositions, hydrogels performance and morphologies of the membranes were determined by Fourier transformed infrared spectroscopy (FTIR), cross-linking degree, swelling degree, membrane flux and scanning electron microscopy (SEM). It is found that PVA cross-linking structure is successfully synthesized on the surface of capsule body and cap due to the presence of PVA in the filament. The lead ions adsorption capacity related to initial concentration of 50 mg/L in 48 h is reached 75.61%, revealing a good removal ability. The self-floating 3D printed capsules device also shows an excellent recovering property. After 7 runs of adsorption experiment, the lead ions adsorption ratio remains 78.56%, which will bring a broad prospect in wastewater treatment, chemical slow release along with sample preparation and separation.

Abstract The electrochemical CO2 reduction reaction (ECO2RR) on Cu catalysts affords high‐value‐added products and is therefore of great practical significance. The outcome and kinetics of ECO2RR remain insufficient, requiring essentially the optimized structure design for the employed Cu catalyst, and also the fine synthesis controls. Herein, synthesis‐controlled structure preferences and the modulation of intermediate's interactions are considered to provide synthesis‐related insights on the design of Cu catalysts for selective ECO2RR. First, the origin of ECO2RR intermediate‐dominated selectivity is described. Advanced structural engineering approaches, involving alloy/compound formation, doping/defect introduction, and the use of specific crystal facets/amorphization, heterostructures, single‐atom catalysts, surface modification, and nano‐/microstructures, are then reviewed. In particular, these structural engineering approaches are discussed in association with diversified synthesis controls, and the modulation of intermediate generation, adsorption, reaction, and additional effects. The results pertaining to synthetic methodology‐controlled structural preferences and the correspondingly motivated selectivity are further summarized. Finally, the current opportunities and challenges of Cu catalyst fabrication for highly selective ECO2RR are discussed.

The Pt-chitosan-TiO2 charge transfer (CT) complex was synthesized via the sol-gel and impregnation method. The synthesized photocatalysts were thoroughly characterized, and their photocatalytic activity were evaluated toward H2 production through water reduction under visible-light irradiation. The effect of the preparation conditions of the photocatalysts (the degree of deacetylation of chitosan, addition amount of chitosan, and calcination temperature) on the photocatalytic activity was discussed. The optimal Pt-10%DD75-T200 showed a H2 generation rate of 280.4 μmol within 3 h. The remarkable visible-light photocatalytic activity of Pt-chitosan-TiO2 was due to the CT complex formation between chitosan and TiO2, which extended the visible-light absorption and induced the ligand-to-metal charge transfer (LMCT). The photocatalytic mechanism of Pt-chitosan-TiO2 was also investigated. This paper outlines a new and facile pathway for designing novel visible-light-driven photocatalysts that are based on TiO2 modified by polysaccharide biomass wastes that are widely found in nature.

The development of a facile method for the synthesis of GaN:ZnO solid solution, an attractive material with a wurtzite-type structure, is vital to enhance its photocatalytic activity toward H2 evolution. Herein, GaN:ZnO solid solution nanorods with diameters of around 180 nm were fabricated by combining the electro-spun method with a sequentially calcinating process. Photocatalytic water-splitting activities of the as-obtained samples loaded with Rh2−yCryO3 co-catalyst were estimated by H2 evolution under visible-light irradiation. The as-prepared GaN:ZnO nanorods at a nitridation temperature of 850 °C showed the optimal performance. Careful characterization of the GaN:ZnO solid solution nanorods indicated that the nitridation temperature is an important parameter affecting the photocatalytic performance, which is related to the specific surface area and the absorbable visible-light wavelength range. Finally, the mechanism of the GaN:ZnO solid solution nanorods was also investigated. The proposed synthesis strategy paves a new way to realize excellent activity and recyclability of GaN:ZnO solid solution nanorod photocatalysts for hydrogen generation.

ZSM-5 molecular sieves (ZSM-5-T1, ZSM-5-T2, ZSM-5-T3) were synthesized using SiO2, SiO2-8.7% C, and SiO2-23.6% C as templates from rice husk powder, respectively. Pt species were fixed within the ZSM-5 skeleton via the isovolumetric impregnation method, and the resulting catalysts were employed for the efficient oxidation of toluene (C7H8). Notably, Pt/ZSM-5-T2 exhibited the highest C7H8 catalytic oxidation activity (R175 °C = 0.733 µmol g-1 s-1, WHSV = 60 000 mL h-1 g-1) among the three variants. Furthermore, this catalyst displayed excellent water resistance when exposed to various concentrations of water vapor (2 vol%, 5 vol%, 8 vol% and 10 vol%) during the activity test. The characterization results provided insight into the exceptional catalytic performance of the Pt/ZSM-5-T2 catalyst, attributing it to its high specific surface area, appropriate hydrophilicity, abundant Lewis acid sites, and a high Pt0/(Pt0 + Pt2+) ratio. In situ DRIFTS analysis further suggested that the key step in the oxidation of C7H8 to benzyl alcohol involves C-H cleavage on Pt/ZSM-5. Simultaneously, the application of a life-cycle assessment (LCA) revealed that this strategy, involving the substitution of chemicals with biomass, led to a remarkable 41-43% reduction in carbon footprint. This environmentally friendly approach underscores the potential for repurposing rice husk powder waste. Pt/ZSM-5-T2 meets the requirements for practical applications, paving the way for sustainable resource utilization in the realm of environmental preservation. [ABSTRACT FROM AUTHOR]

Introduction: The role of TLR4 in ischaemic preconditioning is still unclear; we do not know the change of the expression of TLR4 in the process. In this study, we used ischaemic preconditioning models to observe the change of TLR4 expression and the level of proinflammatory cytokines TNF-α and IL-1β to investigate the protective mechanism of TLR4 in ischaemic preconditioning for myocardial ischaemia-reperfusion injury (MI/RI) in rats., Material and Methods: Eighteen male Sprague-Dawley (SD) rats were randomly separated into sham, ischaemic reperfusion (IR) and ischaemic preconditioning (IP) groups (6/group). Peripheral blood and cardiac muscle with pathological changes were collected after the establishment of the above three animal models. We used ELISA to determine proinflammatory cytokines TNF-α and IL-1β production in serum of these animals. RT-PCR and Western blot were used to assay the transcriptional level and protein level of TLR4 in cardiac muscle tissue with pathological changes, respectively., Results: We found that compared with the IR group, ischaemic preconditioning could effectively reduce the expression levels of TNF-α and IL-1β in sera of rats in the IP group (p < 0.01). Meanwhile, TLR4 mRNA and protein levels were down-regulated (p < 0.01 and p < 0.05, respectively). We also found that infarct size decreased in the IP group compared with the IR group (p < 0.05)., Conclusions: Based on the results, we can conclude that the specific mechanism of ischaemic preconditioning for RI might be closely associated with decreasing expression levels of TLR4 and proinflammatory cytokines such as TNF-α and IL-1β.