Diaqua oxalato strontium(II) complex as a precursor for facile fabrication of Ag-NPs@SrCO3, characterization, optical properties, morphological studies and adsorption efficiency

Enhancing bone scaffold interfacial reinforcement through in situ growth of metal-organic frameworks (MOFs) on strontium carbonate: Achieving high strength and osteoimmunomodulation

Bioceramics have been extensively used to improve osteogenesis of polymers because of their excellent bone-forming capabilities. However, the inadequate interfacial bonding between ceramics and polymers compromises their mechanical properties. In this study, zeolitic imidazolate framework-8 (ZIF-8) was grown in situ on strontium carbonate (SrCO3) to construct a core-shell SrCO3@ZIF-8, which was then added to poly-l-lactic acid (PLLA) to print a SrCO3@ZIF-8/PLLA composite scaffold using selective sintering technology. First, ZIF-8 characterized by its multiple organic ligands, forms a robust interface with PLLA. Second, SrCO3 characterized by its negative zeta potential in solution, exhibits the ability to adsorb positively charged zinc ions. This, in turn, promotes the in situ growth of ZIF-8 on SrCO3, eventually achieving perfect bonding between the second phase and the PLLA matrix. Our findings indicated that the composite scaffold exhibited the highest compressive strength (21.93 MPa) and significantly promoted the osteogenic differentiation of mouse mesenchymal stem cells. Moreover, the in vivo results established that the SrCO3@ZIF-8/PLLA scaffold significantly accelerated bone regeneration efficiency in rat femur defects. The prepared scaffold, with its favorable mechanical properties and osteogenic activity, shows considerable promise for applications in bone repair.

Green Synthesis of Trimetallic Nanocomposite (Ru/Ag/Pd)-Np and Its In Vitro Antimicrobial and Anticancer Activities

In this study, we used the aqueous extract of garlic tunicate leaf to reduce a mixture of equal amounts of ruthenium chloride, silver nitrate, and palladium acetate for the biosynthesis of ruthenium/silver/palladium trimetallic nanocomposite (Ru/Ag/Pd)-Np. Some physicochemical tools were used for nanocomposite characterization, including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), UV-Vis spectroscopy (UV-Vis), scanning electron microscope (SEM), and transmittance electron microscope (TEM). XRD revealed that the crystal size of the nanocomposite is 15.67 nm. The TEM images showed that the particle size ranged 50–90 nm. The antimicrobial efficacy of the nanocomposite was examined against Aspergillus flavus, Aspergillus niger, Candida albicans, Candida glabrata, Escherichia coli, and Bacillus cereus. The results showed a potent antimicrobial activity toward all tested microorganisms. (Ru/Ag/Pd)-Np showed antiproliferative activity against Caco-2, HepG2, and K562 cell lines. The antiproliferative potential of (Ru/Ag/Pd)-Np was significantly improved following UV irradiation.

Removal of Acid Red 88 Using Activated Carbon Produced from Pomelo Peels by KOH Activation: Orthogonal Experiment, Isotherm, and Kinetic Studies

Activated carbon (PPAC) from pomelo peels was prepared by carbonization and KOH activation. The performance of PPAC was assessed by removing acid red 88 (AR88) in aqueous solution. The most suitable activation processes were found by orthogonal experiments, aimed to achieve the maximum of removal capacity of AR88. Moreover, the possible mechanisms of adsorption were studied through the results of characterization, isotherm fitting, and kinetics simulation. Results showed the preparation parameter that mattered the most to AR88 removal efficiency was the activation temperature of PPAC, followed by impregnation ratio and activation time. The optimal preparation conditions of PPAC were at activation temperature 800°C, activation time 90 min, and impregnation ratio 2.5 : 1. The characterization results showed optimal PPAC had a microporous and amorphous carbon structure whose BET specific area and total pore volume were 2504 m2/g and 1.185 cm3/g, respectively. The isotherm fitting demonstrated that the sorption process followed the Langmuir model, and theoretical maximal sorption value was 1486 mg/g. The kinetics simulation showed that the pseudo-second-order model described the sorption behavior better, suggesting chemisorption seemed to be the rate-limiting step in the adsorption process. This work presented that PPAC was a promising and efficient adsorbent for AR88 from water.

Superior UV-light photocatalysts of nano-crystalline (Ni or Co) FeWO4: structure, optical characterization and synthesis by a microemulsion method

A new NiFeWO₄ photocatalyst showing super photocatalytic activity for MB degradation under UV after 60 min due to photoexcited electrons.

Eggshell recycling for fabrication of Pd@CaO, characterization and high-performance solar photocatalytic activity

Recycling of waste materials into useful products is a promising strategy for environmental protection. Eggshell is one of the globally produced huge wastes. In this work, calcium oxide (CaO) nanoparticles were recycled via calcination of chicken eggshells at 1100 °C for 2 h. A novel nanocomposite, made of loading palladium nanoparticles on calcium oxide surface (Pd@CaO), is successfully fabricated through solid-solid interaction. The materials were characterized using different physicochemical techniques: Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), photoluminescence (PL) analysis, ultra-high resolution field emission scanning electron microscope (FE-SEM), transmittance electron microscope (TEM), and X-ray diffraction (XRD). The study sheds light on the ability of the materials to be used for detoxification of crystal violet dye as pollutant model under solar irradiation. The effects of operational conditions, such as catalyst mass, initial dye concentration, pH, and illumination time, have been tested. The optimum conditions for crystal violet photocatalytic degradation in the presence of Pd@CaO were mild conditions. Control experiments studied the effect of sunlight in the absence of the catalyst, and the effect of the catalyst in the absence of sunlight does not provide the significant removal exhibited in the presence of catalyst under solar irradiation.