Features of bismuth and silicon oxides synthesis by pulsed laser ablation in water

Semiconductor nanomaterials are widely used in photocatalysis due to a number of advantages such as efficient electron separation and flexible choice of semiconductor with desired band gap for efficient light absorption. Bismuth silicates (BSO) are promising new photocatalytic materials for organic decomposition and hydrogen production [1]. Currently mainly chemical methods of synthesis are used to obtain BSO materials. In this work for the first time complex oxides BSO were prepared via pulsed laser ablation (PLA) in a liquid. PLA was performed by exposing Si and Bi targets to Nd:YAG laser radiation (1064 nm, 7 ns). Separately synthesized nanocolloids were mixed and subjected to additional laser irradiation and then dried. Using different Si/Bi ratios, as well as temperature treatment of the resulting powders, BSO of various compositions were synthesized, including monophases of the compounds Bi2SiO5, Bi4Si3O12 and Bi12SiO20. The photocatalytic activity of the samples was estimated by the decomposition of Rhodamine B under LED source irradiation with rad = 375 nm. The effect extra irradiation of colloids mixture on the formation of the structure of complex oxides BSO at different Si/Bi ratios has been studied. The correlations between the optical properties, composition and structure of catalysts and their photocatalytic properties has been established. It was shown that the best photocatalytic activity exhibits Bi12SiO20 powders

PLA synthesis and photocatalytic properties of bismuth silicates

In this work, bismuth silicates were obtained by pulsed laser ablation in a liquid (PLA)

Bismuth silicates: preparation by pulsed laser ablation and photocatalytic activity

Pulsed laser ablation (PLA) in liquid is advanced method for obtaining active nanoparticles in pure solvents without the use of chemical precursors. In this work, an original approach to the synthesis of complex oxides of bismuth and silicon (BSO) is proposed. The initial colloids obtained by PLA (Nd:YAG laser, 1064 nm, 7 ns) of Bi and Si targets in water were mixed and subjected to additional irradiation with the same laser parameters. Laser treatment stimulated the formation of complex oxides. Then the colloids were dried in air and nanopowders obtained were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-Vis spectroscopy. The photocatalytic activity of the materials was examined in the Rhodamine B degradation under LED source irradiation (375 nm)

Structure and optical properties of nanocrystalline titanium dioxide prepared via pulsed laser ablation in liquid

Crystal structure and optical properties of titaniu

Effect of laser treatment of TiO2 on optical and photocatalytic properties

Nanomaterials based on dark titanium dioxide are of considerable interest as promising photocatalysts. In this work, titanium dioxide initially obtained by pulsed laser ablation (Nd:YAG laser with 1064 nm, 7 ns, 20 Hz) was subjected to additional laser treatment. The thus obtained powder materials were annealed and study of the structure by X-ray diffraction, optical properties by diffuse reflection spectroscopy, and photocatalytic properties in the processes of decomposition of the Rhodamine B dye and evolution of hydrogen from an aqueous methanol solution are presente

Study of highly defective titanium dioxide prepared via pulsed laser ablation

TiO2 powder was synthesized in the following way. At first, a colloidal solution of Ti in distilled water was obtained by PLA using Nd:YAG laser (wavelength of 1064 nm, frequency of 20 Hz, pulse duration of 7 ns). Then the colloidal solution was dried at 60 °C. After that, the powder was annealed at different temperatures

Effect of extra laser irradiation on the photocatalytic properties of TiO2 obtained by pulsed laser ablation

in this work we study the effect of extra laser irradiation during the preparation by pulsed laser ablation in water on the structure and physicochemical properties of titanium dioxide. Extra laser irradiation leads to a decrease in particle size, a change in structure, and as a result, a change in optical and photocatalytic properties

Laser-based synthesis of TiO2-Pt photocatalysts for hydrogen generation

The development of visible-light active titanium dioxide is one of the key challenges in photocatalysis that stimulates the development of TiO2-based composite materials and methods for their synthesis. Here, we report the use of pristine and Pt-modified dark titanium dioxide prepared via pulsed laser ablation in liquid (Nd:YAG laser, 1064 nm, 7 ns) for photocatalytic hydrogen evolution from alcohol aqueous solutions. The structure, textural, optical, photoelectrochemical, and electrochemical properties of the materials are studied by a complex of methods including X-ray diffraction, low-temperature nitrogen adsorption, electrophoretic light scattering, diffuse reflection spectroscopy, photoelectrochemical testing, and electrochemical impedance spectroscopy. Both the thermal treatment effect and the effect of modification with platinum on photocatalytic properties of dark titania materials are studied. Optimal compositions and experimental conditions are selected, and high photocatalytic efficiency of the samples in the hydrogen evolution reaction (apparent quantum yield of H2 up to 0.38) is demonstrated when irradiated with soft UV and blue LED, i.e., 375 and 410 nm. The positive effect of low platinum concentrations on the increase in the catalytic activity of dark titania is explained

Creation of a magnetic driven gate for THz rays

In this paper, magnetic fluids based on iron oxide Fe3O4 and 5BDSR alloy were obtained. Magnetic particles were obtained by nanosecond pulsed laser ablation. The preparation of the magnetic fluid was carried out by mechanical and ultrasonic stirring in a solution of polymethylphenylsiloxane. It is shown that under the influence of an external magnetic field, the spectral properties of the magnetic fluid of the 5BDSR alloy correspond to characteristics that can be used to create a magnetic gate