Fabrication of core-shell nanocomposites with enhanced photocatalytic efficacy

Copolymerization of anthranilic acid and o-phenylenediamine by a free radical in the presence of nanoparticles of copper hexacyanoferrates for the removal of cesium ions in aqueous solutions

Core–shell nanocomposite of copper hexacyanoferrate copolymer of anthranilic acid with o-phenylenediamine (CHCF-poly-AA-co-OPD)) was synthesized and used as ion exchanger for the removal of cesium ions from wastewater. The nanocomposite was prepared by implantation of CHCF nanoparticles into the copolymer of poly(AA-co-OPD) during the polymerization process. By transmission electron microscope, scanning electron microscope and Brunauer–Emmett–Teller, the surface morphology and the porous structure were investigated. The physicochemical characterization of the prepared core–shell nanocomposite was carried out by FT-IR spectroscopy, XRD and thermogravimetric analysis. As a function in pH, metal ion concentration, shaking time and temperature, the capacity of the CSNC toward cesium ions and the behaviors of the process were studied. The results illustrated that the maximum capacity was recorded 1.35 mmol g−1 at pH 11, 10 mmol L−1 Cs+ and 25 °C. Also, Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) isotherms models were studied, in which the data were well fitted with Langmuir model, suggesting that the uptake of Cs+ was monolayer and homogeneous. Also, the adsorption kinetics data were fitted well to pseudo-second-order model. Thermodynamic parameters were calculated in the temperature from 25 to 60 °C, and the data revealed that Cs+ sorption was endothermic, spontaneous and more favorable at higher temperature. Up to 92% desorption of Cs+ was completed with 2 M KCl.

Core–shell polymer nanocomposite based on free radical copolymerization of anthranilic acid and o-amino phenol in the presence of copper hexacyanoferrates nanoparticles and its adsorption properties

Core–shell polymer nanocomposite (CSNC) of copper hexacyanoferrate-copolymer of anthranilic acid with o-aminophenol (CHCF-poly(AA-co-OAP)) was synthesized and used as ion exchanger for the sorption of cesium ions from aqueous solution. The nanocomposite was prepared by implantation of CHCF nanoparticles into copolymer of poly(AA-co-OAP) during the polymerization process. The surface morphology and the porous structure were investigated through transmission electron microscope (TEM), scanning electron microscope (SEM) and Brunauer–Emmett–Teller (BET). The characterization of the prepared (CSNC) was carried out by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Thermogravimetric (TGA). Which SEM and TEM images confirmed the nano-size of the prepared CSNC. The values of adsorption capacity of CSNC towards cesium ions and the factors influence on the removal of cesium from solutions were investigated as function in pH, metal ion concentration, temperature and contact time. The results illustrated that the highest value of sorption capacity of the prepared CSNC towards Cs+ ions was 2.1 mmol g−1 at pH 11, 10 mmol L−1 Cs+ and 25 °C. Four modeling include on Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) isotherms models were studied. According to the obtained data, Langmuir model considered the most suitable model, which suggest that the uptake of Cs+ was monolayer and homogeneous. Also, the adsorption kinetics data was fitted well to pseudo-second-order model. Thermodynamic parameters were calculated in the temperature from 25 to 60 °C and the data revealed that Cs+ sorption was endothermic, spontaneous, and more favorable at higher temperature. Up to 92% desorption of Cs+ was completed with 2 M KCl.

Core-shell structured cadmium sulfide nanocomposites for solar energy utilization

Solar energy utilization technologies have been widely explored to solve the global energy crisis because the inexhaustible solar energy can be converted into chemical fuel and electricity. Various semiconductors that are crucial for solar energy utilization have been extensively developed. Among them, cadmium sulfide (CdS) has attracted extensive attention due to its suitable band-gap and excellent electrical/optical properties. However, CdS is still limited by rapid charge recombination, instability and low quantum efficiency. Core-shell structures can provide great opportunities for constructing advanced structures with superior properties to overcome the remaining challenges. This review focuses on the significant advances in core-shell structured CdS nanocomposites for solar energy utilization. Initially, the synthetic methods to construct core-shell structured CdS nanocomposites are reviewed. Then the applications in solar energy utilization are discussed, including photocatalytic\photoelectrochemical water splitting, photocatalytic CO₂ reduction and solar cells. Finally, the perspectives of core-shell structured CdS nanocomposites for solar energy utilization are proposed.