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Any labeling with multicolor markers can be affected by the autofluorescence of biological tissue due to the UV or blue light excitation sources, or the results are affected by fluorescence resonance energy transfer. In this work, we present novel IR-to-vis upconverting nanoparticles of different rare earth metal dopants. With a single excitation source of 980 nm, four different colors of nanocrystals can be spectrally separated under multiplexing conditions. The particles were phase transferred into polar solvents by means of silica encapsulation and were characterized by transmission electron microscopy, X-ray diffraction, and photoluminescence spectroscopy.

Core-silica shell nanoparticles were prepared in a "reverse" manner by nucleation and growth of Au cores within hollow silica nanospheres.

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]

[Display omitted] • Cu (II) doped NiO nanoparticles synthesized by high energy ball-milling process. • NPs act as a commendable catalyst for sonophotocatalytic degradation of phenol. • Sonophotocatalytic system shows superiority over the individual US or UV. • Synergistic effect of NPs provided superior sonophotocatalytic performance. Mesoporous nickel oxide nanostructures were synthesized using a solvothermal method. and then doped with Cu2+ via high energy planetary ball milling technique. crystallinity, morphology, porosity, size, and composition of the nanoparticles were evaluated using XRD, BET, TEM, and EDX techniques. The as-prepared doped nanoparticles were used for the first time in the oxidative sonophotocatalytic removing of organic pollutants in low-frequency and low-energy ultrasound waves at room temperature in the presence of visible light. After 60 min of double irradiation (ultrasound + Visible light) in the presence of doped nanoparticles, more than 86 % of the pollutants were removed; reaching a constant rate of 0.0363 min−1. integration ultrasonic and visible light in the oxidative sonophotocatalytic remediation process resulted in a synergistic effect of about 72 %. Above all, the results showed the high reusability and stability of the doped nanoparticles in consecutive runs with minor fading in their sonophotocatalytic performance. To investigate the mechanism, the performance of the oxidative sonophotocatalytic removing process was examined by the addition of different types of trapping and enhancer agents. Finally, the generality of the process was evaluated by the remediation of commercially available antibiotics from water. [ABSTRACT FROM AUTHOR]

Three anodic electrocatalysts containing Ni–Pt core–shell (CNi–SPt), Ni–Pd core–shell (CNi–SPd) and Ni–Ru core–shell (CNi–SRu) nanoparticles were fabricated on reduced graphene oxide (rGO) via a two-step consecutive reduction process. The rGO-based catalysts were characterized via XRD, FE-SEM, EDAX, TEM, HR-TEM and XPS. The effect of CNi–SPt/rGO, CNi–SPd/rGO and CNi–SRu/rGO toward the borohydride oxidation reaction (BOR) was evaluated in a half-cell and also in a single direct borohydride–hydrogen peroxide fuel cell (DBHPFC). The electrochemical measurements indicated that CNi–SPd/rGO exhibited the highest current density for borohydride oxidation (39 085 A g−1) compared to CNi–SPt/rGO (30 790 A g−1) and CNi–SRu/rGO (4563 A g−1) with the same catalyst loading. The highest power density of 310.20 mW cm−2 at a current density of 264 mA cm−2 with 2 M H2O2 and 1 M NaBH4 solution at 60 °C was achieved with CNi–SPd/rGO as a suitable electrocatalyst. This system enhanced the power generation by 32.57% and 80.98% in comparison with that of CNi–SPt/rGO (233.98 mW cm−2) and CNi–SRu/rGO (171.40 mW cm−2), respectively. Thus, this study revealed that CNi–SPd/rGO is a suitable anodic electrocatalyst for application in DBHPFCs in comparison with the commercially used Pt-based electrocatalysts because of its advantages such as low cost, high activity toward the BOR and stability in fuel cells. [ABSTRACT FROM AUTHOR]

The human life faces serious energy shortage and environmental pollution problems, therefore developing a facile and environmental friendly strategy for synthesizing nanoparticles (NPs) with improved photocatalytic activity could pave the way for different applications. In the present study, one-pot/in-situ fluorine-free synthesis process has been examined toward the solvothermal production of anatase TiO 2 nanoparticles with exposed facet orientation. This is an aim to achieve the excellent photocatalytic/photoelectrocatalytic performance. Most importantly addressing the global energy shortage, the synthesized TiO 2 NPs represent superior performance in photoelectrocatalytic water splitting toward hydrogen production. The overpotential required to drive the hydrogen evolution reaction was −391, −346 and −283 mV vs. Ag/AgCl for P25, cubic and truncated octahedral NPs, respectively. Additionally, TiO 2 NPs with exposed facets represent excellent photocatalytic performance toward environmental purification. As synthesized nanoparticles was examined via photocatalytic degradation of Acid Blue 5 and photocatalytic removal of NO gas. The enhanced photocatalytic and photoelectrocatalytic performance are associated to the effect of exposed facet orientation of final nanoparticles. Image 1 • TiO 2 NPs were prepared by a facile and environmental-friendly solvothermal approach. • NPs show a higher photocatalytic activity for hydrogen production. • The excellent photocatalytic activity originates mainly from TiO 2 NPs exposed with active facets. • The photocatalytic activity of as prepared TiO 2 NPs were few times higher than that of P25. [ABSTRACT FROM AUTHOR]

Abstract: The Verwey transition in Fe3O4 nanoparticles with a mean diameter of 6.3 nm is suppressed after capping the particles with a 3.5 nm thick shell of SiO2. By X‐ray absorption spectroscopy and its associated X‐ray magnetic circular dichroism this suppression can be correlated to localized Fe2+ states and a reduced double exchange visible in different site‐specific magnetization behavior in high magnetic fields. The results are discussed in terms of charge trapping at defects in the Fe3O4/ SiO2 interface and the consequent difficulties in the formation of the common phases of Fe3O4. By comparison to X‐ray absorption spectra of bare Fe3O4 nanoparticles in course of the Verwey transition, particular changes in the spectral shape could be correlated to changes in the number of unoccupied d states for Fe ions at different lattice sites. These findings are supported by density functional theory calculations. [ABSTRACT FROM AUTHOR]

The solvothermal synthesis of nanostructured TiO 2 has been studied to examine the processing parameters that control crystallite size, phase, morphology, and facet orientation. Control over the characteristics of these materials makes them useful for a wide range of applications in photocatalysis, environmental pollution remediation, and solar energy conversion. Moreover, this simple, low cost, and low toxicity synthesis process could be extendable to the controlled synthesis of other functional oxide crystals with well-defined morphologies and tunable sizes with active facet orientation. [ABSTRACT FROM AUTHOR]

Nanoparticles deposited on a substrate could be an excellent candidate for environmental and catalytic applications. Herein, TiO 2 nanoparticles were prepared by a solvothermal method and then electrophoretically deposited on a substrate via an in-situ one-pot method. The developed process does not need a washing process (after synthesis), neither sintering nor organic binders (for deposition). Transmission electron microscopy (TEM), used to analyze the deposited nanofilm, confirms that the layer is crack-free and homogeneous. Then sonophotocatalytic performance of TiO 2 nanofilm in the degradation of the organic pollutants (Methylene blue, phenazopyridine) was investigated, since the problem of filtration of the catalyst after the sonophotocatalysis process is eliminated. About 90 % of the organic pollutant was degraded by the sonophotocatalytic process, while the application of ultrasound alone is capable of degrading 14 %, and UV light alone is about 55 %. The synergic effect of ultrasound and UV light was calculated and reported about 59 %. The applicability of the optimized sonophotocalytic system was evaluated by decomposition of a commercial tablet (phenazopyridine), and the efficiency was 84 % in an hour. Most importantly, the reusability of the nanofilm was investigated, and after 4 uses, the nanofilm was able to degrade 84 % of organic pollutants. Owing to its excellent performance, the nanofilm prepared by EPD is suitable for a broad range of environmental and energy applications. • Fabrication of nanofilm through a one-pot in-situ synthesis/ EPD method. • nanofilm act as a commendable catalyst for sonophotocatalytic degradation of organic dye. • Sonophotocatalytic system shows superiority over the individual US or UV. • nanofilm possesses high stability and durability after four consecutive cycles. • Synergistic effect of nanofilm provided superior sonophotocatalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe (III) doped TiO 2 nanoparticles have been synthesized by high energy ball-milling process. • The important advantages of this synthesis are the simplicity, green wet-chemicals method. • The fabricated NPs can significantly enhance electrocatalytic activity of GCE towards the determination of PC. • The sensor was successfully applied for PC detection in commercially available tablets. In this paper, pure and Fe (III) doped TiO 2 nanoparticles were prepared in order to fabricate a nano sensor for electrochemical sensing of paracetamol. TiO 2 nanoparticles as anatase phase were synthesized using a solvothermal method and doped with Fe (III) by mechanochemical planetary ball mill method. For structural and chemical characterization of the as-synthesized nanoparticles, techniques such as X-ray diffraction (XRD), energy dispersive X-ray (EDX), and transmission electron microscopy (TEM) were employed. XRD proved that the nanoparticles, after doping, consist of a mixture of anatase and brookite phases. The performance of the modified electrode was characterized with cyclic voltammetry, differential pulse-voltammetry techniques. The. Fe (III)TiO 2 /GCE modified electrode represents excellent electrocatalytic activity for paracetamol detection in phosphate buffer (pH = 7) solution, with a considerable enhancing of the peak current and decrease of overvoltage in comparison with the bare GCE. It poses a low limit of detection (LOD) and a good linear relationship. The nano sensor showed good sensitivity, selectivity, stability, reproducibility, and fast response. Furthermore, to demonstrate the rapid and convenient determination of paracetamol in pharmaceutical samples, this sensor has been successfully utilized in analyzing real samples, and satisfactory results have been achieved. The response of the nano sensor was linear over the paracetamol concentration range of 1.50–10.2 μM and 10.2–62 μM. The limit of detection (LOD) was calculated to be 0.52 μM (S/N = 3). [ABSTRACT FROM AUTHOR]

[Display omitted] NiO and NiO-Ni nanoparticles were synthesized via a low-cost and simple procedure using solvothermal-calcination method. Our preparation method is a facile and green chemicals process without using toxic/hazardous chemicals or any template. The nanoparticles were used to fabricate a sensor by drop-casting of its solution on a surface of a cleaned glassy carbon electrode. The effectiveness for the electrochemical determination of Metronidazole was confirmed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The modified electrode represented an electrocatalytic response for the analyte with a considerable decrease of overvoltage as well as an enhancing of the peak current in comparison with the bare electrode. The represented sensors showed linear behavior to metronidazole in the concentration range of 0.01–1.44 μmol L−1 (NiO-Ni) and 0.8–3.8 μmol L−1 (NiO) in CV and 0.01–1.63 μmol L−1 (NiO-Ni) and 0.01–0.47 μmol L−1 (NiO) in DPV techniques. The detection limits were found to be 0.007 (CV) and 0.006 (DPV) μmol L−1 for NiO-Ni and 0.4 (CV) and 0.008 μmol L−1 (DPV) for NiO modified electrodes, respectively. Additionally, the modified electrodes have significant benefits such as low cost, convenient preparation, fast response time, good stability, acceptable repeatability, high sensitivity, wide concentration range, and low detection limit. [ABSTRACT FROM AUTHOR]

Herein, NiO nanoparticles were prepared by a facile solvothermal route. The as-synthesized nanoparticles were characterized using XRD, BET, TEM, HRTEM. The BET measurements prove the mesoporous nature of the NPs, having good specific surface area and pore volume. The synthesized NiO NPs were used for the first time in dye decomposition using methylene blue (MB) as a model pollutant in low frequency and low energy ultrasound at pH = 7 and room temperature in presence of UV light and H 2 O 2 as an oxidant. The change of the pollutant concentration was estimated by UV–VIS spectrophotometry. Dye degradation performance investigated for sonocatalysis, photocatalysis, and sonophotocatalysis processes. The data showed that the decomposition performance was in the following order: sonophotocatalysis>photocatalysis>sonocatalysis. After about 30 min of dual (Sono + UV) irradiation in the presence of NiO NPs more than 90% of the pollutant degraded, achieving a rate constant of about 0.089 min−1. Sonophotocatalytic performance was compared with sonocatalysis and photocatalysis processes carried out in the same conditions. Interestingly, the combination of ultrasound and UV light irradiation in a sonophotocatalytic degradation process led to about 33% synergy effect, proving a positive synergy between the sonocatalytic and photocatalytic processes. Reusability data exhibited the excellent stability of sonophotocatalysts within four consecutive runs with negligible fading in their sonophotocatalytic performance. This feature improves the reusability potential of the sonophotocatalysts to be applied in the industrial directions. The obtained results proved that the performance of the sonophotocatalytic process was severely affected by the addition of different kinds of trapping agents, therefore based on these results the mechanism of the sonophotocatalysis was discussed. Finally, the presently combined system paved the way toward excellent efficiency and it could pose a good strategy, in terms of environmental impact and energy cost, in comparison to conventional sonophotocatalytic systems. [Display omitted] • Fabrication of NiO NPs through a simple solvothermal method. • NiO NPs act as a commendable catalyst for sonophotocatalytic degradation of organic dye. • Sonophotocatalytic system shows superiority over the individual US or UV. • NiO NPs possess high stability and durability after four consecutive cycles. • Synergistic effect of NiO NPs provided superior sonophotocatalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of ZnO nanoparticles through a simple and cost-effective method. • Doping ZnO nanoparticles with Fe3+ via high energy planetary ball milling process. • Using XRD, FTIR and FESEM techniques to determine the composition, structure and morphology of nanoparticles. • Investigating the sonophotocatalytic performance of nanoparticles in pollutant degradation. Zinc oxide nanostructures were synthesized using a thermal decomposition method and subsequently doped with Fe (III) in this study. Techniques such as X-ray diffraction, Field emission scanning electron microscopy, and Fourier transform infrared spectroscopy were used to investigate the structural and chemical composition of nanomaterials. Fe-doped ZnO was synthesized using a simple, low-cost planetary high-energy ball milling process. The sonophotocatalytic activity of Fe-doped ZnO under visible light and ultrasonic waves was then studied. Another aspect of this study is the utilization of visible light, which is far more accessible and cost-effective than UV light. Malachite green (MG) and phenol were applied as water-soluble contaminants. MG degraded about 87.65% after 1 h in the presence of a Fe-doped ZnO catalyst under visible light and ultrasonic waves simultaneously. Phenol was degraded by approximately 64.50% under the same conditions. [ABSTRACT FROM AUTHOR]

In this study, a facile process for the synthesis of bimetallic Pd–Co nanotubes on multi-walled carbon nanotubes (MWCNTs) and chemically reduced graphene oxide (rGO) is reported. The synthesized nanocatalysts are characterized by field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX). Catalysts are evaluated for the oxygen reduction reaction (ORR) in basic media. The electrocatalytic performance of Pd–Co supported on rGO and MWCNTs toward ORR is compared with bimetallic and single Pd nanoparticles decorated on Vulcan carbon (XC-72R) by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and rotating disk electrode (RDE) in 0.1 M NaOH solution. The specific electrochemical surface areas of Pd–Co supported on rGO is higher than the corresponding carbon-supported Pd nanoparticles (222.09 vs. 41.57 m2 g−1, respectively). The RDE results confirm that the final product of the oxygen reduction is water and the proposed main path is direct 4 electron transfer process with smooth transfer kinetic rate on the Pd–Co/rGO in comparison to Pd–Co/C. Furthermore, the lower charge transfer resistance of the particles in ORR process for the Pd–Co/rGO compared to single Pd/C catalyst, indicating it could be excellent candidate for ORR in alkaline media. [Display omitted] • The Pd–Co nanocatalysts are successfully synthesized on MWCNTs and reduced GO. • Pd–Co/rGO exhibits high onset potential of −0.012 V vs SCE in alkaline media. • Excellent activity of Pd–Co/rGO and Pd–Co/MWCNTS is observed compared to Pd/C. • The reduced GO can be promising supporting material for low-cost ORR catalyst. [ABSTRACT FROM AUTHOR]