Continuous Synthesis of Ag/TiO2 Nanoparticles with Enhanced Photocatalytic Activity by Pulsed Laser Ablation

A facile and environmental friendly synthesis strategy based on pulsed laser ablation has been developed for potential mass production of Ag-loaded TiO2 (Ag/TiO2) nanoparticles. By sequentially irradiating titanium and silver target substrates, respectively, with the same 1064 nm 100 ns fiber laser, Ag/TiO2 particles can be fabricated. A postannealing process leads to the crystallization of TiO2 to anatase phase with high photocatalytic activity. The phase composition, microstructure, and surface state of the elaborated Ag/TiO2 are characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) techniques. The results suggest that the presence of silver clusters deposited on the surface of TiO2 nanoparticles. The nanostructure is formed through laser interaction with materials. Photocatalytic activity evaluation shows that silver clusters could significantly enhance the photocatalytic activity of TiO2 in degradation of methylene blue (MB) under UV light irradiation, which is attributed to the efficient electron traps by Ag clusters. Our developed Ag/TiO2 nanoparticles synthesized via a straightforward, continuous, and green pathway could have great potential applications in photocatalysis.

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PL Tunable GaN Nanoparticles Synthesis through Femtosecond Pulsed Laser Ablation in Different Environments

Nanomaterials ◽

10.3390/nano10030439 ◽

2020 ◽

Vol 10 (3) ◽

pp. 439 ◽

Cited By ~ 1

Author(s):

Juan Hao ◽

Sijia Xu ◽

Bingrong Gao ◽

Lingyun Pan

Keyword(s):

Laser Ablation ◽

Photoelectron Spectroscopy ◽

Pulse Laser Ablation ◽

Optoelectronic Devices ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Alternative Methods ◽

X Ray ◽

Pl Spectra ◽

Bulk Gan

The tunable photoluminescence (PL) property is very important for gallium nitride (GaN) nanoparticles in the application of ultraviolet and blue optoelectronic devices, while conventional methods are not so satisfactory that alternative methods for preparing GaN nanoparticles should be studied. In this paper, ultra-small and well dispersed GaN nanoparticles are fabricated through femtosecond pulse laser ablation in air, water and ethanol. For the PL spectra of GaN nanoparticles, there are no shifts in air, red shifts in water and blue shifts in ethanol compared with the intrinsic PL spectra of bulk GaN. The X-ray photoelectron spectroscopy (XPS) results demonstrate that the various PL spectra can be due to the different components inside the GaN nanoparticles, which not only have effect on the PL emissions, but also greatly influence the intensity of PL. This study validates that the ablation environment has a great adjustable effect on the properties of GaN nanoparticles.

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Deposit of AlN thin films by nitrogen reactive pulsed laser ablation using an Al target

Revista Mexicana de Física ◽

10.31349/revmexfis.65.345 ◽

2019 ◽

Vol 65 (4 Jul-Aug) ◽

pp. 345 ◽

Cited By ~ 1

Author(s):

F. Chale-Lara ◽

M. Zapata-Torres ◽

F. Caballero-Briones ◽

W. De la Cruz ◽

N. Cruz Gonzalez ◽

...

Keyword(s):

Thin Films ◽

Laser Ablation ◽

Photoelectron Spectroscopy ◽

Hexagonal Phase ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Nitrogen Pressure ◽

Binding Energies ◽

Xps Spectra ◽

X Ray

We report the synthesis of AlN hexagonal thin films by pulsed laser ablation, using Al target in nitrogen ambient over natively-oxidized Si (111) at 600°C. Composition and chemical state were determined by X-ray photoelectron spectroscopy (XPS); while structural properties were investigated using X-ray diffraction (XRD). High-resolution XPS spectra present a gradual shift to higher binding energies on the Al2ppeak when nitrogen pressure is incremented, indicating the formation of the AlN compound. At 30 mTorr nitrogen pressure, theAl2p peak corresponds to AlN, located at 73.1 eV, and the XRD pattern shows a hexagonal phase of AlN. The successful formation of the AlN compound is corroborated by UV-Vis reflectivity measurements.

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Laser Raman and X-ray photoelectron spectroscopy of phosphorus containing diamond-like carbon films grown by pulsed laser ablation methods

Diamond and Related Materials ◽

10.1016/j.diamond.2003.11.069 ◽

2004 ◽

Vol 13 (4-8) ◽

pp. 1442-1448 ◽

Cited By ~ 41

Author(s):

G.M. Fuge ◽

P.W. May ◽

K.N. Rosser ◽

S.R.J. Pearce ◽

M.N.R. Ashfold

Keyword(s):

Laser Ablation ◽

Photoelectron Spectroscopy ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Carbon Films ◽

Diamond Like Carbon ◽

X Ray ◽

Laser Raman ◽

Phosphorus Containing

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Influence of Titania Synthesized by Pulsed Laser Ablation on the State of Platinum during Ammonia Oxidation

Applied Sciences ◽

10.3390/app10144699 ◽

2020 ◽

Vol 10 (14) ◽

pp. 4699

Author(s):

Andrey Stadnichenko ◽

Dmitry Svintsitskiy ◽

Lidiya Kibis ◽

Elizaveta Fedorova ◽

Olga Stonkus ◽

...

Keyword(s):

Laser Ablation ◽

Photoelectron Spectroscopy ◽

Ammonia Oxidation ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Active Species ◽

Laser Ablation In Liquid ◽

X Ray ◽

Catalytically Active ◽

Physicochemical Methods

A set of physicochemical methods, including X-ray photoelectron spectroscopy (XPS), X-ray diraction, electron microscopy and X-ray absorption spectroscopy, was applied to study Pt/TiO2 catalysts prepared by impregnation using a commercial TiO2-P25 support and a support produced by pulsed laser ablation in liquid (PLA). The Pt/TiO2-PLA catalysts showed increased thermal stability due to the localization of the highly dispersed platinum species at the intercrystalline boundaries of the support particles. In contrast, the Pt/TiO2-P25 catalysts were characterized by uniform distributionof the Pt species over the support. Analysis of Pt4f XP spectra shows that oxidized Pt2+ and Pt4+ species are formed in the Pt/TiO2-P25 catalysts, while the platinum oxidation state in the Pt/TiO2-PLA catalysts is lower due to stronger interaction of the active component with the support due to stronginteraction via Pt-O-Ti bonds. The Pt4f XP spectra of the samples after reaction show Pt2+ and metallic platinum, which is the catalytically active species. The study of the catalytic properties in ammonia oxidation showed that, unlike the catalysts prepared with a commercial support, the Pt/TiO2-PLA samples show higher stability during catalysis and significantly higher selectivity to N2 in a wide temperature range of 200–400 C.

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Photocatalytic Degradation of Estriol Using Iron-Doped TiO2 under High and Low UV-Irradiation

10.20944/preprints201809.0583.v1 ◽

2018 ◽

Author(s):

Irwing M. Ramírez-Sánchez ◽

Erick R. Bandala

Keyword(s):

Photocatalytic Activity ◽

Electron Microscope ◽

Uv Irradiation ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Bet Surface Area ◽

Doped Tio2 ◽

X Ray ◽

Transmission Electron ◽

Iron Doped

Iron Doped TiO2 nanoparticles (Fe-TiO2) were synthesized and photocatalitically investigated under high and low fluence values of UV-radiation. The Fe-TiO2 physical characterization was performed using X-ray Powder Diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Diffuse Reflectance Spectroscopy (DRS), and X-Ray Photoelectron Spectroscopy (XPS) technique. The XPS evidenced that ferric ion (Fe3+) was in the lattice of TiO2 and co-dopants no intentionally added were also present due to the precursors of the synthetic method. The Fe3+ concentration played a key role in the photocatalytic generation of hydroxyl radical (•OH) and estriol (E3) degradation. Fe-TiO2 materials accomplished E3 degradation, and it was found that the catalyst with 0.3 at. % content of Fe (0.3 Fe-TiO2) enhanced the photocatalytic activity under low UV-irradiation compared with no intentionally Fe-added TiO2 (zero-iron TiO2) and Aeroxide® TiO2 P25. Furthermore, the enhanced photocatalytic activity of 0.3 Fe-TiO2 under low UV-irradiation may have applications when radiation intensity must be controlled, as in medical applications, or when strong UV absorbing species are present in water.

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Influence of Cu(NO3)2 content used in thermal shock method on the photocatalytic activity of Cu-Modified ZnO nanoparticles

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v5i2.1042 ◽

2021 ◽

Vol 5 (3) ◽

pp. first

Author(s):

Thế Luân Nguyễn ◽

Tiến Khoa Lê ◽

Châu Ngọc Hoàng ◽

Hữu Khánh Hưng Nguyễn ◽

Thị Kiều Xuân Huỳnh

Keyword(s):

Crystal Structure ◽

Methylene Blue ◽

Photocatalytic Activity ◽

Thermal Shock ◽

Photoelectron Spectroscopy ◽

Copper Content ◽

Uv Light ◽

Copper Nitrate ◽

X Ray ◽

Doped Zno

The Cu doped ZnO photocatalysts were prepared on ZnO substrate modified with copper nitrate by thermal shock method with different ratio % molar Cu : Zn = 0.3, 0.5, 1.0, 2.0 and 5.0 in order to study the impacts of copper content on the photocatalytic activity of ZnO under both UV and Vis light irradiation. The crystal structure, morphology bulk and surface were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Their photocatalytic activities were studied via time-dependent degradation of methylene blue in aqueous solution. The results exhibit that crystal structure and morphology of Cu doped ZnO photocatalysts is not modified significally than ZnO original but surface charateristicschanged greatly. The photocatalyst was doped with copper content under 2% showed formation of Cu species. These samples perform photocatalytic activity higher than ZnO. The CuNZO-0.05-500 had the highest rate constants for methylene blue degradation (kUV = 6,901 h-1, kVIS = 0,224 h-1), which are about 2.2 times and 1.3 times higher than unmodified ZnO under UV light and Vis light, respectively. However, the CuNZO-5.0-500 which had the formation of CuO phase and unchangeable ZnO's surface has photocatalytic activity similar to pure ZnO.

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