182 Facile microwave-assisted synthesis of monodispersed ball-like Ag@AgBr photocatalyst with high activity and durability
This paper, written by researchers from Ocean University of China and others, discusses Facile microwave-assisted synthesis of monodispersed ball-like Ag@AgBr photocatalyst with high activity and durability. The paper is published in an important journal < Applied Catalysis A: General >.IF：4.521.
In recent years, the research work of microwave chemical instrument used in the synthesis of materials has become a hot direction of scientific research, which has been paid great attention to by many scholars!
We reported a rapid one-step microwave-assisted approach to synthesize a plasmonic photocatalyst of ball-like AgBr nanoparticles (ca. 290 nm in average diameter) with a small amount of metal Ag anchored on the surface. The obtained Ag@AgBr nanocomposites were characterized by means of X-ray diffraction, scanning electron microscopy, Transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and UV-visible diffuse reflectance spectroscopy. The shape, size, and compositions of the Ag@AgBr photocatalysts could be controlled by tuning the microwave irradiation time and the concentrations of polyvinylpyrrolidone (PVP) in the reaction solution. The as-prepared Ag@AgBr plasmonic photocatalysts show excellent visible-light photocatalytic performance and good reusability for decomposing organic pollutant of Rhodamine B (RhB) due to the surface plasmon resonance (SPR) effect of Ag nanoparticles. Meanwhile, the possible degradation pathways of RhB and a mechanism of the plasmonic photocatalytic process were also proposed.
In summary, we have successfully synthesized Ag@AgBr plasmonic photocatalysts with ball-like morphology through a simple one-step microwave-assisted approach. The shape, size, and composition of the Ag@AgBr nanocomposites were well controlled by tuning the microwave irradiation time and the concentrations of PVP. The as-prepared Ag@AgBr plasmonic photocatalysts show excellent photocatalytic performance under visible light irradiation, which is attributed to the SPR effect of the metallic silver component. Meanwhile, the possible degradation pathways of RhB and a mechanism of the plasmonic photocatalytic process was also proposed. It is believed that the obtained Ag@AgBr plasmonic photocatalyst with high activity and strong durability has potential applications in the degradation of organic contaminations and environmental cleaning.
Ag@AgBr photocatalysts were synthesized by a facile and rapid microwave-assisted nonaqueous route. In a typical procedure, 15 mL of EG was cooled to 0 ◦C in an ice bath, then 2 mmol of AgNO3 was dissolved in it to form a clear solution. In a separate beaker, 2 mmol of NaBr and 3 mmol of PVP were added to 15 mL of EG, followed by sonication at room temperature to form a homogeneous solution, and then was slowly dropped to the AgNO3 solution under vigorous stirring for 30 min. The resulting mixture was transferred to a 100 mL flask, and the flask was placed into a XH-MC-1 microwave reactor system (XiangHu Science and Technology Equipment Co., Ltd., Beijing, China). The mixture was heated to 160 ◦C by microwave irradiation and kept at the temperature for 10 min. Then the reaction system was quickly cooled to room temperature by an ice bath. The obtained products were collected by centrifugation, washed with absolute ethanol several times, and then dried in vacuum at 45 ◦C for 12 h. The sample was denoted as T-10. In the control experiment, the time series of samples denoted as T-20 and T-30 represent the samples prepared for 20 min and 30 min, respectively, with identical other conditions.