scholarly journals Surface-Modified Titanium Dioxide Nanofibers with Gold Nanoparticles for Enhanced Photoelectrochemical Water Splitting

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 261 ◽  
Author(s):  
Van Nghia Nguyen ◽  
Minh Vuong Nguyen ◽  
Thi Hong Trang Nguyen ◽  
Minh Thuy Doan ◽  
Loan Le Thi Ngoc ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Titanium Dioxide ◽  
Water Splitting ◽  
Xenon Lamp ◽  
Hydrogen Energy ◽  
Au Nps ◽  
X Ray ◽  
Tio2 Nanofiber ◽  
Surface Modified

High-stability, high-efficiency, and low-cost solar photoelectrochemical (PEC) water splitting has great potential for hydrogen-energy applications. Here, we report on gold/titanium dioxide (Au/TiO2) nanofiber structures grown directly on a conductive indium tin oxide substrate, and used as photoelectrodes in PEC cells for hydrogen generation. The titanium dioxide nanofibers (TiO2 NFs) are synthesized using electrospinning, and are surface-modified by the deposition of gold nanoparticles (Au NPs) using a simple photoreduction method. The structure and morphology of the materials were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The surface plasmon resonance (SPR) of the Au NPs was investigated by ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy. The PEC properties of the as-prepared photoelectrodes were measured. The obtained photoconversion efficiency of 0.52% under simulated-sunlight illumination by a 150 W xenon lamp of the Au/TiO2 NFs structure with 15 min UV irradiation for Au NP deposition was the highest value from comparable structures. Working photoelectrode stability was tested, and the mechanism of the enhanced PEC performance is discussed.

AQUEOUS-BASED FORMATION OF GOLD NANOPARTICLES ON SURFACE-MODIFIED COTTON TEXTILES

2013 ◽  
Vol 01 (01) ◽  
pp. 1250001 ◽  
Author(s):  
HONGJUN LIU ◽  
WEI-PENG GOH ◽  
TYLER B. NORSTEN
Keyword(s):  
Gold Nanoparticles ◽  
Surface Treatment ◽  
Photoelectron Spectroscopy ◽  
Fiber Surface ◽  
Vinyl Pyrrolidone ◽  
Cotton Fibers ◽  
Au Nps ◽  
X Ray ◽  
Cotton Textiles ◽  
Surface Modified

A facile and environmental friendly route has been developed to synthesize gold nanoparticles (AuNPs) by using amine stabilizers and N-vinyl pyrrolidone (NVP) as the reductant in an aqueous medium. This synthetic concept can be applied to the formation of Au NPs on normal cotton fibers via in situ surface modification of the cotton fibers by (3-aminopropyl)triethoxysilane (ATS) followed by nanoparticle formation. This scheme produces red Au NP-dyed cotton textiles. Surface treatment of the cotton textiles by ATS was found to be crucial for the formation of nano- Au . X-ray photoelectron spectroscopy (XPS), diffused reflectance UV-visible spectroscopy (UV-vis) and energy dispersive X-ray (EDX) were used to investigate the fiber surfaces. The distribution of Au NPs as well as surface treatment agent on the fiber surface was located by time of flight secondary ion mass spectroscopy (TOF-SIMS).

scholarly journals Effects of Different Surfactant Charges on the Formation of Gold Nanoparticles by the LASiS Method

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2937
Author(s):  
Muhammad Zulfajri ◽  
Wei-Jie Huang ◽  
Genin-Gary Huang ◽  
Hui-Fen Chen
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Laser System ◽  
Synthesis Process ◽  
Au Nps ◽  
Laser Fluences ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
532 Nm

The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

Synthesis and Study the Properties of a Solar Cell of Gold Nanoparticles Prepared in a Simple Chemical Way

2021 ◽  
Vol 19 (11) ◽  
pp. 66-71
Author(s):  
Maithm A. Obaid ◽  
Suha A Fadaam ◽  
Osama S. Hashim
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Chemical Method ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Casting Method ◽  
X Ray ◽  
Transmission Electron ◽  
Simple Chemical ◽  
Scanning Electron

The aim of this study is to prepare gold nanoparticles by a simple chemical method at a temperature of 70°C. The solution was dried on glass basest by Casting method, the rate of five drops per sample At a temperature 100 C. Then the structural and optical properties have been confirmed by X-ray diffraction, scanning electron microscopy (SEM) and Transmission Electron microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and spectrum.

Aquatic Fern (AzollaSp.) Assisted Synthesis of Gold Nanoparticles

2016 ◽  
Vol 15 (01n02) ◽  
pp. 1650008 ◽  
Author(s):  
Anal K. Jha ◽  
K. Prasad
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gold Nanoparticles ◽  
Surface Plasmon Resonance ◽  
Au Nanoparticles ◽  
X Ray ◽  
Aquatic Fern ◽  
Transmission Electron ◽  
Anthraquinone Glycosides ◽  
Uv Visible

Aquatic pteridophyte (Azolla sp.) was taken to assess its potential to synthesize the metal (Au) nanoparticles. The synthesized particles were characterized using X-ray, UV-visible, scanning and transmission electron microscopy analyses. Nanoparticles almost spherical in shape having the sizes of 5–17[Formula: see text]nm are found. UV-visible study revealed the surface plasmon resonance at 538[Formula: see text]nm. Responsible phytochemicals for the transformation were principally phenolics, tannins, anthraquinone glycosides and sugars present abundantly in the plant thereby bestowing it adaptive prodigality. Also, the use of Azolla sp. for the synthesis of gold nanoparticles offers the benefit of eco-friendliness.

scholarly journals Ni2P/rGO/NF Nanosheets As a Bifunctional High-Performance Electrocatalyst for Water Splitting

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 744 ◽  
Author(s):  
Jinyu Huang ◽  
Feifei Li ◽  
Baozhong Liu ◽  
Peng Zhang
Keyword(s):  
Electron Microscopy ◽  
Water Splitting ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
High Efficiency ◽  
Splitting Method ◽  
Bifunctional Catalyst ◽  
Strong Activity ◽  
X Ray ◽  
Transmission Electron

The hydrogen generated via the water splitting method is restricted by the high level of theoretical potential exhibited by the anode. The work focuses on synthesizing a bifunctional catalyst with a high efficiency, that is, a nickel phosphide doped with the reduced graphene oxide nanosheets supported on the Ni foam (Ni2P/rGO/NF), via the hydrothermal approach together with the calcination approach specific to the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). The Raman, X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscope (TEM), Scanning Electron Microscopy (SEM), High-Resolution Transmission Electron Microscopy (HRTEM), as well as elemental mapping, are adopted to study the composition and morphology possessed by Ni2P/rGO/NF. The electrochemical testing is performed by constructing a parallel two-electrode electrolyzer (Ni2P/rGO/NF||Ni2P/rGO/NF). Ni2P/rGO/NF||Ni2P/rGO/NF needs a voltage of only 1.676 V for driving 10 mA/cm2, which is extremely close to Pt/C/NF||IrO2/NF (1.502 V). It is possible to maintain the current density for no less than 30 hours. It can be demonstrated that Ni2P/rGO/NF||Ni2P/rGO/NF has commercial feasibility, relying on the strong activity and high stability.

scholarly journals Comparison of Gold Nanoparticles Deposition Methods and Their Influence on Electrochemical and Adsorption Properties of Titanium Dioxide Nanotubes

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4269 ◽  
Author(s):  
Ewa Paradowska ◽  
Katarzyna Arkusz ◽  
Dorota G. Pijanowska
Keyword(s):  
Gold Nanoparticles ◽  
Titanium Dioxide ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Photoelectron Spectroscopy ◽  
Bovine Serum ◽  
Electrochemical Impedance ◽  
Electrochemical Characterizations ◽  
Titanium Dioxide Nanotubes ◽  
X Ray

The increasing interest of attachment of gold nanoparticles (AuNPs) on titanium dioxide nanotubes (TNTs) has been devoted to obtaining tremendous properties suitable for biosensor applications. Achieving precise control of the attachment and shape of AuNPs by methods described in the literature are far from satisfactory. This work shows the comparison of physical adsorption (PA), cyclic voltammetry (CV) and chronoamperometry (CA) methods and the parameters of these methods on TNTs properties. The structural, chemical, phase and electrochemical characterizations of TNTs, Au/TNTs, AuNPs/TNTs are carried out using scanning electron microscopy (SEM), electrochemical impedance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy. The use of PA methods does not allow the deposition of AuNPs on TNTs. CV allows easily obtaining spherical nanoparticles, for which the diameter increases from 20.3 ± 2.9 nm to 182.3 ± 51.7 nm as a concentration of tetrachloroauric acid solution increase from 0.1 mM to 10 mM. Increasing the AuNPs deposition time in the CA method increases the amount of gold, but the AuNPs diameter does not change (35.0 ± 5 nm). Importantly, the CA method also causes the dissolution of the nanotubes layer from 1000 ± 10.0 nm to 823 ± 15.3 nm. Modification of titanium dioxide nanotubes with gold nanoparticles improved the electron transfer and increased the corrosion resistance, as well as promoted the protein adsorption. Importantly, after the deposition of bovine serum albumin, an almost 5.5-fold (324%) increase in real impedance, compared to TNTs (59%) was observed. We found that the Au nanoparticles—especially those with smaller diameter—promoted the stability of bovine serum albumin binding to the TNTs platform. It confirms that the modification of TNTs with gold nanoparticles allows the development of the best platform for biosensing applications.

Application of Titanium Dioxide (TiO2) Based Photocatalytic Nanomaterials in Solar and Hydrogen Energy: A Short Review

2012 ◽  
Vol 712 ◽  
pp. 25-47 ◽  
Author(s):  
Amir Al-Ahmed ◽  
Bello Mukhtar ◽  
Safdar Hossain ◽  
S.M. Javaid Zaidi ◽  
S.U. Rahman
Keyword(s):  
Titanium Dioxide ◽  
Hydrogen Storage ◽  
Water Splitting ◽  
Electronic Band Structure ◽  
Structural Phase ◽  
Research Work ◽  
Size Variation ◽  
Minimum Size ◽  
Hydrogen Energy ◽  
Electronic Band

Tremendous amount of research work is going on Titanium dioxide (TiO2) based materials. These materials have many useful applications in our scientific and daily life and it ranges from photovoltaics to photocatalysis to photo-electrochromics, sensors etc.. All these applications can be divided into two broad categories such as environmental (photocatalysis and sensing) and energy (photovoltaics, water splitting, photo-/electrochromics, and hydrogen storage). Synthesis of TiO2nanoparticles with specific size and structural phase is crucial, for solar sell application. Monodispersed spherical colloids with minimum size variation (5% or less) is essential for the fabrication of photonic crystals. When sensitized with organic dyes or inorganic narrow band gap semiconductors, TiO2can absorb light into the visible light region and convert solar energy into electrical energy for solar cell applications. TiO2nanomaterials also have been widely studied for water splitting and hydrogen production due to their suitable electronic band structure given the redox potential of water. Again nanostructured TiO2has extensively been studied for hydrogen storage with good storage capacity and easy releasing procedure. All these issues and related finding will be discussed in this review.

Chemical Synthesis of Magnetic Fe3O4 Nanoparticles

2005 ◽  
Vol 475-479 ◽  
pp. 2275-2278 ◽  
Author(s):  
Rui Feng Yang ◽  
Yu Zhen Lv ◽  
Yahui Zhang ◽  
Chen Min Liu ◽  
Lin Guo
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fe3o4 Nanoparticles ◽  
Solution Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Solution Method ◽  
Transmission Electron ◽  
Wet Chemical ◽  
Surface Modified

Fe3O4 nanoparticles were simply prepared by a wet chemical solution method. In this method, poly (N-vinyl-2-pyrrolidone) (PVP) was used as surface modified reagent to control the shape of the product. Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD) were used to characterize the asprepared Fe3O4 nanoparticles. Furthermore, the magnetic properties of the sample were investigated by a VSM (vibrating sample magnetometer) technique.

scholarly journals Application of Titanium Dioxide-Graphene Composite Material for Photocatalytic Degradation of Alkylphenols

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Chanbasha Basheer
Keyword(s):  
Electron Microscopy ◽  
Titanium Dioxide ◽  
Photocatalytic Efficiency ◽  
Ionization Detector ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Composite ◽  
Flame Ionization ◽  
Transmission Electron ◽  
Wastewater Samples

Titanium dioxide-graphene (TiO2-G) composite was used for the photodegradation of alkylphenols in wastewater samples. The TiO2-G composites were prepared via sonochemical and calcination methods. The synthesized composite was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), and fluorescence spectroscopy. The photocatalytic efficiency was evaluated by studying the degradation profiles of alkylphenols using gas chromatography-flame ionization detector (GC-FID). It was found that the synthesized TiO2-G composites exhibit enhanced photocatalytic efficiencies as compared to pristine TiO2. The presence of graphene not only provides a large surface area support for the TiO2photocatalyst, but also stabilizes charge separation by trapping electrons transferred from TiO2, thereby hindering charge transfer and enhancing its photocatalytic efficiency.

Sign in / Sign up

Export Citation Format

Share Document