scholarly journals Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1456
Author(s):  
Yujie Fu ◽  
You Zhang ◽  
Qi Xin ◽  
Zhong Zheng ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Surface Oxidation ◽  
Treatment Method ◽  
X Ray ◽  
Chlorinated Volatile Organic Compounds ◽  
Volatile Organic ◽  
Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

scholarly journals Enhanced Photocatalytic Activity of Titania by Co-Doping with Mo and W

Catalysts ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 631 ◽  
Author(s):  
Osmín Avilés-García ◽  
Jaime Espino-Valencia ◽  
Rubí Romero-Romero ◽  
José Rico-Cerda ◽  
Manuel Arroyo-Albiter ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Absorption Capacity ◽  
Radiation Absorption ◽  
Experimental Conditions ◽  
X Ray ◽  
Assembly Method ◽  
Co Doped

Various W and Mo co-doped titanium dioxide (TiO2) materials were obtained through the EISA (Evaporation-Induced Self-Assembly) method and then tested as photocatalysts in the degradation of 4-chlorophenol. The synthesized materials were characterized by thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectroscopy (RS), N2 physisorption, UV-vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The results showed that the W-Mo-TiO2 catalysts have a high surface area of about 191 m2/g, and the presence of an anatase crystalline phase. The co-doped materials exhibited smaller crystallite sizes than those with one dopant, since the crystallinity is inhibited by the presence of both species. In addition, tungsten and molybdenum dopants are distributed and are incorporated into the anatase structure of TiO2, due to changes in red parameters and lattice expansion. Under our experimental conditions, the co-doped TiO2 catalyst presented 46% more 4-chlorophenol degradation than Degussa P25. The incorporation of two dopant cations in titania improved its photocatalytic performance, which was attributed to a cooperative effect by decreasing the recombination of photogenerated charges, high radiation absorption capacity, high surface areas, and low crystallinity. When TiO2 is co-doped with the same amount of both cations (1 wt.%), the highest degradation and mineralization (97% and 74%, respectively) is achieved. Quinones were the main intermediates in the 4-chlorophenol oxidation by W-Mo-TiO2 and 1,2,4-benzenetriol was incompletely degraded.

Hydrothermal Synthesis and Characterization of Phosphor Doped Tetragonal Zirconia Nanocrystallites

2011 ◽  
Vol 197-198 ◽  
pp. 846-852
Author(s):  
Jian Jun Yin ◽  
Tao Wang ◽  
Wei Jing Xing
Keyword(s):  
Photoelectron Spectroscopy ◽  
Raw Materials ◽  
High Surface ◽  
High Surface Area ◽  
Tetragonal Zirconia ◽  
Zirconium Oxychloride ◽  
Dihydrogen Phosphate ◽  
Hydrothermal Conditions ◽  
Hydrothermal Temperature ◽  
X Ray

Using zirconium oxychloride hydrate ( ZrOCl2•8H2O) and ammonia water (NH3•H2O) as raw materials, and ammonium dihydrogen phosphate (NH4H2PO4) as additives, tetragonal zirconia (t-ZrO2) with size range of 8–12 nm were prepared by coprecipitation method under hydrothermal conditions. The influence factors on phase transformation and the particle size such as phosphor loading, hydrothermal temperature and calcination temperature were studied by X-ray diffraction (XRD), Fourier transform Roman spectra (FT-Roman), the Brunauer-Emmett-Teller (BET) method and X-ray photoelectron spectroscopy (XPS) techniques etc. Research results show that a small amount of phosphor has been incorporated into the framework of ZrO2 crystals, producing a certain amount of oxygen vacancies. Phosphor can effectively restrain crystal particles growth and improve the thermal stability of metastable t-ZrO2. The phosphor doped t-ZrO2 had a high surface area (244.2 m2/g). In contrast to the pure ZrO2 particles readily aggregating, the phosphor species deposited on the framework of ZrO2 crystals prevented the agglomeration of the primary particles during calcinations.

Synthesis and capacitive properties of carbonaceous sphere@MnO2 rattle-type hollow structures

2010 ◽  
Vol 25 (8) ◽  
pp. 1476-1484 ◽  
Author(s):  
Jintao Zhang ◽  
Jizhen Ma ◽  
Jianwen Jiang ◽  
X.S. Zhao
Keyword(s):  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
Hollow Spheres ◽  
High Surface Area ◽  
Mesoporous Structure ◽  
Experimental Conditions ◽  
X Ray ◽  
Hollow Structures ◽  
Capacitive Properties

Carbonaceous sphere@MnO2 rattle-type hollow spheres were synthesized under mild experimental conditions. The as-prepared hollow structures were characterized using scanning electron microscope, transmission electron microscope, x-ray diffraction, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and nitrogen adsorption techniques. The characterization data showed the formation of rattle-type hollow structures with a mesoporous MnO2 shell and a carbonaceous sphere core. The composition and shell thickness of the hollow spheres can be controlled experimentally. The capacitive performance of the hollow structures was evaluated by using both cycle voltammetry and charge–discharge methods. The results demonstrated a specific capacitance as high as 184 F/g at a current density of 125 mA/g. The good electrocapacitive performance resulted from the mesoporous structure and high surface area of the MnO2-based hollow spheres.

scholarly journals Mesoporous CdO/Al2O3 nanocomposite with enhanced optoelectronic properties for visible-light photocatalysis and bactericidal applications

2021 ◽  
Author(s):  
Janani B ◽  
Asad Syed ◽  
Abdallah M. Elgorban ◽  
Ali H. Bahkali ◽  
S. Sudheer Khan
Keyword(s):  
Photoelectron Spectroscopy ◽  
Organic Contaminants ◽  
Dye Degradation ◽  
High Surface ◽  
High Surface Area ◽  
Energy Shift ◽  
Band Gap Energy ◽  
Oh Radicals ◽  
X Ray ◽  
Viable Solution

Abstract Pristine Al2O3 and CdO are known to possess poor photocatalytic activity individually. The formation of CdO/Al2O3 heterojunction was investigated for the enhancement of photocatalytic performance. High resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) has been used to determine the crystalline feature and elemental composition of the NCs respectively. Peaks ascribed to Cd-O and O-Al-O was noted in fourier-transform infrared spectroscopy (FTIR) analysis. The NCs exhibits a high surface area (27.23 m2/g) to their contributing particles which was analysed using BET analyser. The band gap energy of CdO/Al2O3NCs was observed to be 2.95 eV which shows a considerable energy shift from its individual particles, CdO (2.73 eV) and Al2O3 (3.94 eV). The results displayed that the degradation efficiency of the CdO-Al2O3 NCs was enhanced 14 times than pristine Al2O3 and 3.5 times than pristine CdO. The MB dye has showed the half life period of 80 min. TOC analysis of degraded product supported high mineralization of the pollutants. The dye degradation was driven by OH. radicals and the CdO-Al2O3 nanocomposite possessed high reusability which was confirmed by six cycle test. Growth inhibition of E. coli, P. aeruginosa and B. subtilis was attained by exposure to CdO/Al2O3 NCs. The CdO-Al2O3 NCs can be a viable solution for degradation of organic contaminants effectively under natural sun light as well as an efficient antibacterial agent.

Ni-doped, urchin-like Bi2S3 particles for electrocatalytic oxidation of glucose

2021 ◽  
pp. 2150006
Author(s):  
Biao Wang ◽  
Ya Liu ◽  
Xu Huai ◽  
Yuqing Miao
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Electrocatalytic Oxidation ◽  
High Surface ◽  
High Surface Area ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Capacitance Current ◽  
Oxidation Of Glucose

In order to develop non-noble metal-based electrocatalysts for glucose oxidation, the Ni-doped, urchin-like Bi2S3 particles were prepared by a solvothermal method using the solvent of ethylene glycol/H2O. The obtained products were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The background signal from capacitance current is relatively low and the electrocatalytic oxidation current of glucose relatively high due to the urchin-like nanostructure of Bi2S3 particles and high surface area where the presence of Bi also improves the electrocatalytic performance of NiII/NiIII shift.

scholarly journals Synthesis and Introducing Au-Cu Alloy Nanoparticles/Porous Silicon as a Novel Modifier of Screen Printed Carbon Electrode in Simultaneous Electrocatalytic Detection of Codeine and Acetaminophen

2022 ◽  
Author(s):  
Farzad Allahnouri ◽  
Khalil Farhadi ◽  
Hamideh Imanzadeh ◽  
Rahim Molaei ◽  
Habibollah Eskandari
Keyword(s):  
Porous Silicon ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Galvanic Replacement ◽  
Human Blood Plasma ◽  
Carbon Electrode ◽  
X Ray ◽  
Screen Printed Carbon Electrode ◽  
Screen Printed

Abstract In the present study, a bimetallic nanostructure of gold-copper (Au-CuNPs) was decorated on the surface of porous silicon (PSi) using an easy galvanic replacement reaction between metal ions and PSi in the presence of 0.1 M hydrofluoric acid solution. The morphology and structures of the Au-CuNPs@PSi nanocomposite were characterized using X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) energy-dispersive X-ray spectroscopy (EDX) and cyclic voltammetry (CV) techniques. Then, prepared nanocomposite was used as a modifier in screen-printed carbon electrode (SPCE) for the highly sensitive simultaneous determination of codeine (COD) and acetaminophen (ACE). The combination of PSi and metals nanoparticles provide a porous and high surface area with excellent electrical conductivity which leads to reduce the peak potentials and enhance the oxidation peak currents of COD and ACE at the surface of the Au-CuNPs@PSi/SPCE nanosensor. The dynamic linear ranges were obtained from 0.06 to 0.6 µM for both COD and ACE and the detection limits (3.0 S/N) estimated 0.35 µM for COD and 0.30 µM for ACE, respectively. Moreover, recovery tests were carried out in real samples such as urine, human blood plasma, and tablets.

scholarly journals Nanotubular Titanium Oxynitride with an Ultra-Low Iridium Loading as a High-Performance Oxygen-Evolution-Reaction Thin-Film Electrode

2020 ◽  
Author(s):  
Marjan Bele ◽  
Primož Jovanovič ◽  
Živa Marinko ◽  
Sandra Drev ◽  
Vid Simon Šelih ◽  
...  
Keyword(s):  
Thin Film ◽  
Oxygen Evolution ◽  
Photoelectron Spectroscopy ◽  
Oxygen Evolution Reaction ◽  
High Performance ◽  
High Surface ◽  
High Surface Area ◽  
Additional Contribution ◽  
X Ray ◽  
Metal Support Interaction

The present study targets one of the grand challenges of electrochemical hydrogen production: a durable and cost-effective oxygen-evolution catalyst. We present a thin-film composite electrode with a unique morphology and an ultra-low loading of iridium that has extraordinary electrocatalytic properties. This is accomplished by the electrochemical growth of a defined, high-surface-area titanium oxide nanotubular film followed by the nitridation and effective immobilization of iridium nanoparticles. The applicative relevance of this production process is justified by a remarkable oxygen-evolution reaction (OER) activity and high stability. Due to the confinement inside the pores and the strong metal-support interaction (SMSI) effects, the OER exhibited a higher turnover. The high durability is achieved by self-passivation of the titanium oxynitride (TiON) surface layer with TiO<sub>2</sub>, which in addition also effectively embeds the Ir nanoparticles, while still keeping them electrically wired. An additional contribution to the enhanced durability comes from the nitrogen atoms, which according to our DFT calculations reduce the tendency of the Ir nanoparticles to grow. We also introduce an advanced electrochemical characterization platform for the in-depth study of thin-film electrodes. Namely, the entire process of the TiON-Ir electrode’s preparation and the electrochemical evaluation can be tracked with scanning electron microscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) at identical locations. In general, the novel experimental approach allows for the unique morphological, structural and compositional insights into the preparation and electrocatalytic performance of thin films, making it useful also outside electrocatalysis applications.

scholarly journals Lanthanum based high surface area perovskite-type oxide and application in CO and propane combustion

2018 ◽  
Vol 34 (1) ◽  
pp. 31
Author(s):  
Paulo Roberto Nagipe Da Silva ◽  
Ana Brígida Soares
Keyword(s):  
Catalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Perovskite Phase ◽  
High Surface ◽  
High Surface Area ◽  
Propane Combustion ◽  
Total Oxidation ◽  
X Ray ◽  
Co Precipitation ◽  
Perovskite Type

The perovskite-type oxides using transition metals present a promising potential as catalysts in total oxidation reaction. The present work investigates the effect of synthesis by oxidant co-precipitation on the catalytic activity of perovskite-type oxides LaBO3 (B= Co, Ni, Mn) in total oxidation of propane and CO. The perovskite-type oxides were characterized by means of X-ray diffraction, nitrogen adsorption (BET method), thermo gravimetric and differential thermal analysis (ATG-DTA) and X-ray photoelectron spectroscopy (XPS). Through a method involving the oxidant co-precipitation it’s possible to obtain catalysts with different BET surface areas, of 33-44 m2/g, according the salts of metal used. The characterization results proved that catalysts have a perovskite phase as well as lanthanum oxide, except LaMnO3, that presents a cationic vacancies and generation for known oxygen excess. The results of catalytic test showed that all oxides have a specific catalytic activity for total oxidation of CO and propane even though the temperatures for total conversion change for each transition metal and substance to be oxidized.

Nanotubular Titanium Oxynitride with an Ultra-Low Iridium Loading as a High-Performance Oxygen-Evolution-Reaction Thin-Film Electrode

2020 ◽  
Author(s):  
Marjan Bele ◽  
Primož Jovanovič ◽  
Živa Marinko ◽  
Sandra Drev ◽  
Vid Simon Šelih ◽  
...  
Keyword(s):  
Thin Film ◽  
Oxygen Evolution ◽  
Photoelectron Spectroscopy ◽  
Oxygen Evolution Reaction ◽  
High Performance ◽  
High Surface ◽  
High Surface Area ◽  
Additional Contribution ◽  
X Ray ◽  
Metal Support Interaction

The present study targets one of the grand challenges of electrochemical hydrogen production: a durable and cost-effective oxygen-evolution catalyst. We present a thin-film composite electrode with a unique morphology and an ultra-low loading of iridium that has extraordinary electrocatalytic properties. This is accomplished by the electrochemical growth of a defined, high-surface-area titanium oxide nanotubular film followed by the nitridation and effective immobilization of iridium nanoparticles. The applicative relevance of this production process is justified by a remarkable oxygen-evolution reaction (OER) activity and high stability. Due to the confinement inside the pores and the strong metal-support interaction (SMSI) effects, the OER exhibited a higher turnover. The high durability is achieved by self-passivation of the titanium oxynitride (TiON) surface layer with TiO<sub>2</sub>, which in addition also effectively embeds the Ir nanoparticles, while still keeping them electrically wired. An additional contribution to the enhanced durability comes from the nitrogen atoms, which according to our DFT calculations reduce the tendency of the Ir nanoparticles to grow. We also introduce an advanced electrochemical characterization platform for the in-depth study of thin-film electrodes. Namely, the entire process of the TiON-Ir electrode’s preparation and the electrochemical evaluation can be tracked with scanning electron microscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) at identical locations. In general, the novel experimental approach allows for the unique morphological, structural and compositional insights into the preparation and electrocatalytic performance of thin films, making it useful also outside electrocatalysis applications.

Sorption of actinides onto nanodiamonds

2015 ◽  
Vol 103 (3) ◽  
Author(s):  
Yulia Buchatskaya ◽  
Anna Romanchuk ◽  
Ruslan Yakovlev ◽  
Andrei Shiryaev ◽  
Inna Kulakova ◽  
...  
Keyword(s):  
Surface Chemistry ◽  
Sorption Capacity ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Sorption Properties ◽  
Closed Chamber ◽  
X Ray ◽  
Commercial Scale ◽  
Low Weight

AbstractDetonation nanodiamonds (ND) present a significant part of nanocarbons group, which could be produced on commercial scale by detonation of explosives in a closed chamber. Their unique properties of high surface area, low weight and radiation resistance make ND a prospective candidate for applications in sorption processes in radiochemistry. To study the influence of surface chemistry on sorption properties, apristine sample of ND was treated with acids and hydrogen. The surface chemistry of the samples was characterised by infrared spectroscopy, X-ray photoelectron spectroscopy and Boehm titration. The sorption properties of ND were tested fordifferent radionuclides. The sorption capacity of ND was shown to be higher than those of commonly used radionuclide sorbents like activated carbon and compariable to other members of nanocarbon group like graphene oxide and carbon nanotubes. The sorption properties were shown to be influenced by the presence of oxygen-containing groups on the surface of ND. This represents an opportunity to increase the sorption capacity of ND.

Sign in / Sign up

Export Citation Format

Share Document