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Orthorhombic perovskite GdFeO 3 nanostructures are promising materials with multiferroic properties. In this study, a new low-temperature plasma-assisted approach is developed via dual anodic dissolution of solid metallic precursors for the preparation of perovskite GdFeO 3 nanoparticles (NPs) that can be collected both as colloids as well as deposited as a thin film on a substrate. Two solid metallic foils of Gd and Fe are used as precursors, adding to the simplicity and sustainability of the method. The formation of the orthorhombic perovskite GdFeO 3 phase is supported by high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman measurements, while a uniform elemental distribution of Gd, Fe, and O is confirmed by energy dispersive X-ray spectroscopy, proving the successful preparation of ternary compound NPs. The magnetic properties of the NPs show zero remnant magnetization typical of antiferromagnetic materials, and saturation at high fields that can be caused by spin interaction between Gd and Fe magnetic sublattices. The formation mechanism of ternary compound NPs in this novel plasma-assisted method is also discussed. This method is also modified to demonstrate the direct one-step deposition of thin films, opening up opportunities for their future applications in the fabrication of magnetic memory devices and gas sensors., (© 2024 The Author(s). Small Methods published by Wiley‐VCH GmbH.)

The work reports on the use of laser ablation and post-ablation irradiation techniques for the preparation Nd 3+ doped ZnO nanoparticles (NPs). The focus has been made on photoluminescence of Nd-doped ZnO NPs in the second near infrared (NIR-II) spectral window (1000-1700 nm) of the biological transparency. Morphology, phase composition and optical properties of the synthesized NPs were studied by absorption and photoluminescence spectroscopy, X-Ray diffraction (XRD) and transmission (TEM) electron microscopy. Near-infrared luminescence of Nd 3+ doped ZnO nanocrystals in the region of 1000-1400 nm was detected both upon excitation from the ground state (800 nm) and upon UV excitation. The latter proves the incorporation of the Nd 3+ into ZnO lattice as photoluminescence occurs through the transfer of excitation energy from the ZnO matrix to the Nd 3+ ion. The possibility of control over the luminescence properties by a variation of solvent composition and by additional laser irradiation was demonstrated., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors.)

Binary (Gd 5 Si 4 , GdSi) and ternary (Gd 5 Si 2 Ge 2 ) compound nanoparticles (NPs) were prepared by laser irradiation of a mixture of colloidal solutions containing NPs of the relevant elements. It is assumed that the compound NPs are formed by heating, co-melting, and chemical interactions in the alloyed droplets. The blackbody-like radiation of the heated NPs was used for temperature control of the NP-preparation process. The obtained results demonstrate that laser irradiation of colloidal NPs provides unique possibilities not only for the synthesis of compound NPs but also for control of their phase composition and size. The synthesized Gd-based compound NPs exhibited magnetic transition at an ordering temperature, T C , in the range of 310-320 K. Thus, the magnetic properties of the synthesized particles confirm their potential for biomedical applications, in particular, for magnetic hyperthermia treatment., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this paper, we report the one-step synthesis of luminescent carbon nanoparticles (NPs) via laser irradiation of a graphite target in a solvent [H 2 O, ethanol, or a 0.008 m aqueous diethylenetriaminepentaacetic acid (DTPA) solution]. This is a simple approach for the fabrication of carbon dots with tunable photoluminescence (PL) that differs from other preparation methods, as no post-passivation step is required. The unfocused beam of the second harmonic (wavelength 532 nm) of the Nd:YAG laser was used in our experiments. The sizes of the prepared NPs were mainly distributed in the range of 1-8 nm with an average value of 3 nm. Carbon NPs of different inner structure were prepared: hexagonal diamond phase in aqueous DTPA solution, orthorhombic carbon phase in ethanol, and amorphous carbon in water. The synthesized carbon NPs have strong luminescence in the visible region, which makes them attractive for numerous biological applications. The photoluminescence of the synthesized NPs was investigated at different excitation wavelengths, from 260 to 450 nm. The highest intensities of the emission bands were detected for an excitation wavelength of 400 nm., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)