scholarly journals Experimental Investigation on the Effects of Photocatalysis in Ultraviolet-Induced Nanoparticle Colloid Jet Machining

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1070
Author(s):  
Xiaozong Song ◽  
Shundong Ge ◽  
Xiaorong Wang ◽  
Shengkai Liu
Keyword(s):  
Tio2 Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Hydrodynamic Pressure ◽  
Active Centers ◽  
Xps Spectra ◽  
Workpiece Surface ◽  
Surface Polishing ◽  
Ft Ir ◽  
Nanoparticle Colloid

In this paper, ultraviolet (UV)-induced nanoparticle colloid jet machining is proposed to achieve ultrasmooth surface polishing by using the interaction between nanoparticles and the workpiece surface under the action of the ultraviolet field and the hydrodynamic pressure field. In the process of UV-induced nanoparticle colloid jet machining, the effects of photocatalysis on the interaction between nanoparticles and the workpiece surface need to be further studied in order to better understand the polishing process. This paper presents the interaction between TiO2 nanoparticles and a Si workpiece surface with and without ultraviolet irradiation. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) were applied to investigate the differences in the interaction of TiO2 nanoparticles with Si workpieces. The SEM and XPS results indicate that the photocatalysis of UV light can promote the interaction between TiO2 nanoparticles and a Si surface by creating more interfacial reaction active centers between the TiO2 nanoparticles and the Si workpiece. The FT-IR and XPS spectra show that TiO2 nanoparticles are chemically bonded to the Si workpiece by oxygen-bridging atoms in Ti-O-Si bonds. Due to the effects of photocatalysis, UV-induced nanoparticle colloid jet machining has a higher polishing efficiency than nanoparticle colloid jet machining with the same polishing parameters.

Preparation and Characterization of Ni2+-Montmorillonite/Polyvinyl Alcohol Water-Soluble Nanocomposite Film

2005 ◽  
Vol 13 (8) ◽  
pp. 839-846 ◽  
Author(s):  
Li-Ping Wang ◽  
Yun-Pu Wang ◽  
Fa-Ai Zhang
Keyword(s):  
Polyvinyl Alcohol ◽  
Photoelectron Spectroscopy ◽  
Thermal Characteristics ◽  
Water Soluble ◽  
Scanning Calorimetry ◽  
Xps Spectra ◽  
X Ray ◽  
Alcohol Water ◽  
Ft Ir ◽  
Silicate Layers

A new type of nano-composite film was prepared from polyvinyl alcohol, Ni2+-montmorillonite (Ni2+-MMT), defoamer, a levelling agent and a plasticizer. Its thermal characteristics were studied by Differential Scanning Calorimetry (DSC). The intermolecular interactions were measured by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the tensile strength (TS) and elongation at break (%E) were measured. The microstructures were studied by X-ray diffraction (XRD) and atomic force microscopy (AFM). FT-IR and XPS spectra indicated that cross-linking has taken place between PVA and Ni2+-MMT. XRD and AFM indicate that the PVA molecules had inserted themselves into the silicate layers of MMT, exfoliating them and dispersing them randomly into the PVA matrix. Compared to pure PVA film, the TS of the films was increased and %E decreased when the Ni2+-Montmorillonite was added and the dissolution temperature of the film was also reduced.

ZnS NANOFLOWERS ON GRAPHENE FOR USE AS A HIGH-PERFORMANCE PHOTOCATALYST

NANO ◽  
2014 ◽  
Vol 09 (08) ◽  
pp. 1450097 ◽  
Author(s):  
ZENG BIN ◽  
LONG HUI
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Dye Degradation ◽  
Uv Light ◽  
Xps Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Potential Applications

The nanocomposites of graphene loaded– ZnS nanoflowers (GR– ZnS ) had been successfully prepared. Materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS) spectra. A possible formation mechanism of this architecture was proposed. The experimental results revealed that these nanoflowers exhibited excellent UV-light photocatalytic activities for pollutant methyl orange (MO) dye degradation. These new nanostructures were expected to show considerable potential applications in the water treatment.

scholarly journals Non-Enzymatic Glucose Biosensor Based on Highly Pure TiO2 Nanoparticles

Biosensors ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 149
Author(s):  
Hongin Jeong ◽  
Jhongryul Yoo ◽  
Seokyung Park ◽  
Jiling Lu ◽  
Sungho Park ◽  
...  
Keyword(s):  
Tio2 Nanoparticles ◽  
Structural Properties ◽  
Polymer Films ◽  
Photoelectron Spectroscopy ◽  
Glucose Sensor ◽  
Conductive Polymer ◽  
Glucose Biosensor ◽  
Pure Tio2 ◽  
Xps Spectra ◽  
X Ray

This study proposes a non-enzymatic glucose sensor fabricated by synthesizing high-purity TiO2 nanoparticles in thermal plasma and depositing it directly on a substrate and then depositing chitosan–polypyrrole (CS-PPy) conductive polymer films by electrochemical method. The structural properties of the deposited TiO2 nanoparticles were analyzed by X-ray diffraction (XRD) and dynamic light scattering (DLS) system. The chemical composition and structural properties of the TiO2 nanoparticle layer and the conductive polymer films were confirmed by X-ray photoelectron spectroscopy (XPS) spectra and scanning electron microscope (SEM). The glucose detection characteristics of the fabricated biosensor were determined by cyclic voltammetry (CV). CS-PPy/TiO2 biosensor showed high sensitivity of 302.0 µA mM−1 cm−2 (R2 = 0.9957) and low detection limit of 6.7 μM. The easily manufactured CS-PPy/TiO2 biosensor showed excellent selectivity and reactivity.

scholarly journals On the Degradation of Glyphosate by Photocatalysis Using TiO2/Biochar Composite Obtained from the Pyrolysis of Rice Husk

Water ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 3326
Author(s):  
Phuong Thu Le ◽  
Duy Ngoc Le ◽  
Thi Hue Nguyen ◽  
Huyen Thuong Bui ◽  
Le Anh Pham ◽  
...  
Keyword(s):  
Tio2 Nanoparticles ◽  
Rice Husk ◽  
Uv Light ◽  
Sol Gel ◽  
Catalyst Support ◽  
Operating Conditions ◽  
Porous Support ◽  
Photodegradation Efficiency ◽  
Ft Ir ◽  
Rice Husk Biochar

In this study, titanium dioxide (TiO2) nanoparticles are immobilized onto rice husk biochar (RHB), as a porous support, for the photodegradation of glyphosate under UV light irradiation. The TiO2/RHB composites are prepared by pyrolysis and the sol-gel method. The SEM, XRD, EDX, and FT-IR results confirm the graphene structure of RHB and the formation of 10.61 nm TiO2 nanoparticles on the catalyst support. The effects of operating conditions, including catalyst dosage (3 g L−1, 5 g L−1, 10 g L−1, and 20 g L−1) and different illumination conditions (9 W lamp, 2 × 9 W lamps), on the removal of glyphosate from aqueous solutions were investigated. The photodegradation efficiency of 15 mg L−1 of commercial glyphosate was up to 99% after 5 h of irradiation at pH 3.0, with a TiO2/RHB dosage of 10 g L−1. However, the mineralization efficiency under this condition was lower than the decomposition efficiency of glyphosate, proving the partial degradation of glyphosate into AMPA and other metabolites after 5 h of reaction.

scholarly journals Enhanced Mechanical and Thermal Properties of Stereolithography 3D Printed Structures by the Effects of Incorporated Controllably Annealed Anatase TiO2 Nanoparticles

Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 79 ◽  
Author(s):  
Suhail Mubarak ◽  
Duraisami Dhamodharan ◽  
Nidhin Divakaran ◽  
Manoj B. Kale ◽  
T. Senthil ◽  
...  
Keyword(s):  
Tio2 Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Anatase Phase ◽  
Low Energy ◽  
Mechanical And Thermal Properties ◽  
Tem Analysis ◽  
X Ray ◽  
Energy Bandgap ◽  
3D Printed

Fabrication of low-cost, durable and efficient metal oxide nanocomposites were successfully synthesized and reinforced with photo-resin via 3-dimensional printing. Here, we put forward a novel approach to enhance the mechanical and thermal behaviors of stereolithography (SLA) 3D printed architecture by adding TiO2 nanoparticles (TNPs) in different crystalline phases (anatase and rutile), which were obtained at different annealing temperatures from 400 °C to 1000°C. The heat-treated anatase TNPs were scrutinized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, diffusive reflectance spectroscopy (DRS), and transmission electron microscopy (TEM) analysis. Among all the samples, at 800 °C, annealed anatase TNPs exposed a highly crystalline anatase phase, having a low energy bandgap and a comparably high tensile strength (47.43 MPa) and high elastic modulus (2.261 GPa) for the 3D printed samples, showing improvement by 103% and 32%, respectively, compared with the printed pristine stereolithography resin (SLR) sample. Moreover, enhanced storage modulus and tan δ values were achieved via the better interfacial interactions between the incorporated nanofillers and the SLR matrix. In addition to this, enhanced thermal conductivity and thermal stability of the SLR matrix were also noted. The low energy bandgap and nanoscale size of the fillers helped to achieve good dispersion and allowed the UV light to penetrate at a maximum depth through the photo resin.

scholarly journals Efficient degradation of picric acid using rGO-MnO2 hybrid nanocomposite under different light conditions

2021 ◽  
Vol 2070 (1) ◽  
pp. 012089
Author(s):  
B Usharani ◽  
V Manivannan ◽  
P Shanmugasundaram
Keyword(s):  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Picric Acid ◽  
Environmental Pollutant ◽  
Light Sources ◽  
Light Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Light Medium

Abstract Picric acid is a very dangerous environmental pollutant generated from chemical and dye industries due to its high toxicity. Therefore, efforts have been made to develop techniques for the efficient degradation of picric acid. A novel rGO-MnO2 nanocomposite has been synthesized by chemical method for the degradation of picric acid in various light medium. The rGO-MnO2 nanocomposite was characterized by X-ray Photoelectron Spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Energy dispersive X-ray (EDAX), Ultraviolet-visible (UV-Vis) and Scanning electron microscope (SEM). The synthesized, pure rGO, MnO2 and rGO-MnO2 nanocomposite catalyst have been studied for the activity of photocatalytic degradation against picric acid under different light sources such as UV light (254,365,390 nm), visible light and sunlight. It is found that rGO-MnO2 has achieved better performance compared to that of pure rGO, MnO2.

scholarly journals Characterization of Tio2 And An As-Prepared Tio2/Sio2 Composite And Their Photocatalytic Performance For The Reduction Of Low-Concentration N-NO3- In Water

2021 ◽  
Author(s):  
Wanzhen Zhong ◽  
Weizhang Fu ◽  
Shujuan Sun ◽  
Lingsheng Wang ◽  
Huaihao Liu ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Photocatalytic Performance ◽  
Uv Light ◽  
Removal Rate ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Load Rate ◽  
Hole Scavenger ◽  
Ft Ir

Abstract Excessive N-NO3- water pollution has become a widespread and serious problem that threatens human and ecosystem health. Here, a TiO2/SiO2 composite photocatalyst was prepared via the sol-gel/hydrothermal method. TiO2 and TiO2/SiO2 were characterized by X-ray diffraction (XRD), UV-Vis differential reflectance spectroscopy (DRS), Fourier infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Afterward, the photocatalytic performance of TiO2 and TiO2/SiO2 to reduce low nitrate concentrations (30 mgN·L-1) under UV light were evaluated and the effects of different factors on this process were investigated, after which the reaction conditions were optimized. Removal rates of up to 99.93% were achieved at a hole scavenger (formic acid) concentration of 0.6 mL·L-1, a CO2 flow rate of 0.1 m3·h-1, and a TiO2 concentration of 0.9 g·L-1. In contrast, TiO2/SiO2 at a 1.4 g·L-1 concentration and a TiO2 load rate of 40% achieved a removal rate of 83.48%,But with more than 98% of nitrogen generation rate.NO2- and NH4+ were the minor products, whereas N2 was the main product.

Mechano-Chemical Modification of Nanodiamond with GW

2008 ◽  
Vol 375-376 ◽  
pp. 87-91
Author(s):  
Yong Wei Zhu ◽  
Xiang Yang Xu ◽  
Bai Chun Wang ◽  
Jian Liang Shen
Keyword(s):  
Fourier Transform ◽  
Chemical Modification ◽  
Photoelectron Spectroscopy ◽  
Silane Coupling Agent ◽  
Xps Spectra ◽  
X Ray ◽  
Silane Coupling ◽  
Before And After ◽  
New Type ◽  
Ft Ir

Mechano-chemical modification (MCM) of nanodiamond was conducted with a stirring mill. A new type of silane coupling agent, GW was chosen as its modifier. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) were employed to study the surface properties of nanodiamond before and after treatments. Results showed that the peaks related to GW and the ball (for example, Fe, Si and Cl) appeared obviously after its MCM on their XPS spectra and mostly disappeared after its further purification with acid X or Y. A new peak located at 1382.48cm-1 was very strong after further purification. It was proven by their FT-IR spectra.

scholarly journals Domino Reaction for the Sustainable Functionalization of Few-Layer Graphene

Nanomaterials ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 44 ◽  
Author(s):  
Vincenzina Barbera ◽  
Luigi Brambilla ◽  
Alberto Milani ◽  
Alberto Palazzolo ◽  
Chiara Castiglioni ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Density Functional ◽  
Cycloaddition Reaction ◽  
Domino Reaction ◽  
Thermal Treatments ◽  
X Rays ◽  
Xps Spectra ◽  
Graphene Layers ◽  
Ft Ir ◽  
Bulk Structure

The mechanism for the functionalization of graphene layers with pyrrole compounds was investigated. Liquid 1,2,5-trimethylpyrrole (TMP) was heated in air in the presence of a high surface area nanosized graphite (HSAG), at temperatures between 80 °C and 180 °C. After the thermal treatments solid and liquid samples, separated by centrifugation, were analysed by means of Raman, Fourier Transform Infrared (FT-IR) spectroscopy, X-Rays Photoelectron Spectroscopy (XPS) and 1H-Nuclear Magnetic Resonance (1H NMR) spectroscopy and High Resolution Transmission Electron Microscopy (HRTEM). FT-IR spectra were interpreted with the support of Density Functional Theory (DFT) quantum chemical modelling. Raman findings suggested that the bulk structure of HSAG remained substantially unaltered, without intercalation products. FT-IR and XPS spectra showed the presence of oxidized TMP derivatives on the solid adducts, in a much larger amount than in the liquid. For thermal treatments at T ≥ 150 °C, IR spectral features revealed not only the presence of oxidized products but also the reaction of intra-annular double bond of TMP with HSAG. XPS spectroscopy showed the increase of the ratio between C(sp2)N bonds involved in the aromatic system and C(sp3)N bonds, resulting from reaction of the pyrrole moiety, observed while increasing the temperature from 130 °C to 180 °C. All these findings, supported by modeling, led to hypothesize a cascade reaction involving a carbocatalyzed oxidation of the pyrrole compound followed by Diels-Alder cycloaddition. Graphene layers play a twofold role: at the early stages of the reaction, they behave as a catalyst for the oxidation of TMP and then they become the substrate for the cycloaddition reaction. Such sustainable functionalization, which does not produce by-products, allows us to use the pyrrole compounds for decorating sp2 carbon allotropes without altering their bulk structure and smooths the path for their wider application.

scholarly journals Removal Mechanism Investigation of Ultraviolet Induced Nanoparticle Colloid Jet Machining

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 68
Author(s):  
Xiaozong Song ◽  
Gui Gao
Keyword(s):  
Tio2 Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Material Removal ◽  
Density Functional ◽  
Hydroxyl Groups ◽  
Removal Mechanism ◽  
The Density Functional Theory ◽  
Point Injection ◽  
Ultra Precision ◽  
Nanoparticle Colloid

Ultraviolet induced nanoparticle colloid jet machining is a new ultra-precision machining technology utilizing the reaction between nanoparticles and the surface of the workpiece to achieve sub-nanometer ultra-smooth surface manufacturing without damage. First-principles calculations based on the density functional theory (DFT) were carried out to study the atomic material removal mechanism of nanoparticle colloid jet machining and a series of impacting and polishing experiments were conducted to verify the mechanism. New chemical bonds of Ti-O-Si were generated through the chemical adsorption between the surface adsorbed hydroxyl groups of the TiO2 cluster and the Si surface with the adsorption energy of at least −4.360 eV. The two Si-Si back bonds were broken preferentially and the Si atom was removed in the separation process of TiO2 cluster from the Si surface realizing the atomic material removal. A layer of adsorbed TiO2 nanoparticles was detected on the Si surface after 3 min of fixed-point injection of an ultraviolet induced nanoparticle colloid jet. X-ray photoelectron spectroscopy results indicated that Ti-O-Si bonds were formed between TiO2 nanoparticles and Si surface corresponding to the calculation result. An ultra-smooth Si workpiece with a roughness of Rq 0.791 nm was obtained by ultraviolet induced nanoparticle colloid jet machining.

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