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In this research, pure and Cu(II)‐doped TiO2 nanoparticles (NPs) were synthesized via a simple and nontoxic approach to fabricate a nanocatalyst for the oxidative sonophotocatalytic degradation of phenol. TiO2 NPs were prepared using a solvothermal method and doped with Cu(II) by high‐energy planetary ball mill. The as‐synthesized NPs were identified and characterized by X‐ray diffraction, energy‐dispersive X‐ray, and transmission electron microscopy techniques. The doped NPs were used for the first time in pollutant decomposition using phenol as a model pollutant in low‐energy and low‐frequency ultrasound at room temperature and pH = 7 in the presence of visible light. The progress of the pollutant degradation was followed by UV–Vis spectrophotometry. After about 60 min of sonophotocatalytic process (dual irradiation [visible light + ultrasound] in the presence of doped NPs), around 75% of the phenol degraded, with a rate constant of about 0.024 min−1. The sonophotocatalytic process was compared with photocatalysis and sonocatalysis processes conducted in the same conditions. Importantly, the combination of visible light and ultrasound irradiation in a sonophotocatalytic decomposition reaction represented about 58% of the synergy effect, demonstrating a positive synergy between the photocatalytic and sonocatalytic processes. The optimum condition was used to degrade the commercial sample (amoxicillin) with excellent performance. The reusability test represented the excellent stability of doped catalysts within four consecutive runs with less fading in their sonophotocatalytic reaction. This feature proves the reusability potential of the doped catalyst to be used in the commercial and industrial directions. The performance of the doped catalyst was affected severely by the addition of different scavengers, and based on the results, the sonophotocatalytic mechanism was discussed. [ABSTRACT FROM AUTHOR]

With the rapid industry development in the last decades, air pollution has increased with the increase in carbon dioxide (CO2). Adsorbents are considered a good candidate for capturing CO2 owing to their many advantages, such as reusability, low cost, easy operation, and scale-up synthesis. In this study, the synthesis of mesoporous cobalt oxide (Co3O4) nanoparticles (NPs) in deep eutectic solvent (DES) is reported by the ultrasound-assisted method to improve the CO2 adsorption performance. The synthesized Co3O4 NPs were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) for investigating morphology, crystallinity, and porosity. CO2 and N2 adsorption isotherms of Co3O4 NPs synthesized in DES and synthesized in water were measured by quartz crystal microbalance (QCM) at a temperature range of 288.15–308.15 K and pressures of up to 5 bar. In addition, CO2/N2 selectivity adsorption on the Co3O4 NPs was investigated. Furthermore, adsorption isotherms were correlated to the Langmuir isotherm model. The results reveal that the adsorption performance of Co3O4 NPs synthesized in DES improved in comparison with Co3O4 NPs synthesized in water. The Co3O4 NPs' molar enthalpy of adsorption showed that the CO2 adsorption process is exothermic. [ABSTRACT FROM AUTHOR]

In recent years, mesoporous cobalt oxides have attracted more attention due to their exceptional physical and chemical properties and their important applications in various fields. The synthesis of cobalt oxides of various sizes, morphologies, and porosity is still a challenging process. In this report, mesoporous Co3O4 NPs with different porosity were synthesized through facile, one-step, and cost-effective routes, without using any complicated materials or instruments, via the sonochemical process. X-ray powder diffraction (XRD), BET, and transmission electron microscopy (TEM) were used to characterize the as-synthesized NPs. XRD technique was used to determine the crystal structure and phase of the NPs, BET to describe the porous nature of the NPs, and TEM to investigate the structure and morphology of the NPs. Next, the effect of as-synthesized Co3O4 NPs as a catalyst for the luminol-H2O2 chemiluminescence system was studied. Co3O4 NPs were chosen since they have nanoscale size, high specific surface area, and mesoporous nature. Therefore, these NPs can form more active sites and thus show unique catalytic activity than common ionic catalysts such as Co2+, Fe3+, Cu2+ used in the luminol-H2O2 CL system. Finally, this system was used to detect and measure H2O2 and glucose under optimal conditions. A good linear relationship was observed between the chemiluminescence intensity of the designed system and the concentration of H2O2 and glucose. A linear range like 0.25â€"10 pM for H2O2 and 1â€"30 nM for glucose was obtained. The excellent LOD of the proposed method for measuring H2O2 was about 0.07 pM, and for measuring glucose was about 0.14 nM. [ABSTRACT FROM AUTHOR]

Correction for 'Improved the CO2 adsorption performance in cobalt oxide nanoparticles in the presence of DES' by Narmin Noorani et al., New J. Chem., 2023, 47, 16748–16755, https://doi.org/10.1039/D3NJ02469E. [ABSTRACT FROM AUTHOR]