7 documents found, page 1 of 1
Ag Nanoparticles-Based Zinc Hydroxide-Layered Hybrids as Novel and Efficient Ca...
Quites,Fernando Junior; Azevedo,Camila K. S.; Alves,Everton P. P.; Germino,José Carlos; Vinhas,Rita C. G.; Landers,Richard; Terezo,Ailton JoséSilver nanoparticles and zinc hydroxide-layered hybrid materials (AgNPs/ZHL) have been successfully developed as efficient catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with sodium borohydride. A facile and rapid visible-light assisted green route was used for the deposition of silver nanoparticles (AgNPs) on the external surface of ZHL material. The resulting AgNPs/ZHL hybrids con...
The Effect of Co and Zn Addition on Densification and Electrical Properties of ...
Villas-Boas,Lúcia Adriana; Nascente,Pedro Augusto de Paula; Landers,Richard; Campos,Marcelo; Souza,Dulcina Maria Pinatti Ferreira deAbstract In this work, cobalt and zinc-doped Ce0.8Gd0.2O1.9 samples were prepared starting from a commercial nanopowder and compared to the undoped material. The powder samples were pressed and afterwards sintered by a two-step procedure, before characterization by X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Impe...
Phosphoric acid adsorbed on silica-ceria matrix obtained by sol-gel method: stu...
Pissetti,Fábio L.; Francisco,Maria Suzana P.; Landers,Richard; Gushikem,YoshitakaSiO2/CeO2 mixed oxide (designated as SC) with variable ceria contents, SC1 = 5.6, SC2 = 8.0 and SC3 = 13.0 wt%, prepared by the sol-gel processing method, were obtained as amorphous solids possessing specific surface areas of SC1 = 463, SC2 = 474 and SC3 = 460 m²g-1. Phosphate ions were immobilized onto the surface of these solids through Ce-O-P bonding by immersing SC into a phosphoric acid solution. Solids wi...
Thin film of copper hexacyanoferrate dispersed on the surface of a conducting c...
Marafon,Eduardo; Lucho,Alzira M.S.; Francisco,Maria S.P.; Landers,Richard; Gushikem,YoshitakaSiO2/ZrO2/C-graphite materials (SZC) were prepared by the sol-gel method presenting two compositions and designated as: (a) SZC30 (SiO2= 50%, ZrO2= 20%, C= 30%) and (b) SZC20 (SiO2 =60%, ZrO2= 20%, C= 20%) in wt.%. The material structure was investigated by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). The electrical conductivities...
Adsorption of phosphoric acid on niobium oxide coated cellulose fiber: preparat...
Pavan,Flávio A.; Francisco,Maria Suzana P.; Landers,Richard; Gushikem,YoshitakaThe preparation procedures for a hybrid organic-inorganic cellulose-niobium oxide (Cel/Nb2O5) and its derivative, Cel/Nb2O5/phosphate, are described. The precursor reagent of the metal oxide was the very convenient water soluble niobium oxalate compound, NH4[NbO(C2O4)2)(H 2O)2].nH2 O. Phosphate ion was adsorbed on the Cel/Nb2O5 by immersing this solid in an aqueous solution of phosphoric acid. Textural analyses...
The ion exchange properties and equilibrium constants of Li+, Na+ and K+ on zir...
Borgo,Claudemir Adriano; Lazarin,Angélica M; Kholin,Yuriy V; Landers,Richard; Gushikem,YoshitakaHighly dispersed zirconium phosphate was prepared by reacting celullose acetate/ZrO2 (ZrO2 = 11 wt%, 1.0 mmol g-1 of zirconium atom per gram of the material) with phosphoric acid. High power decoupling magic angle spinning (HPDEC-MAS) 31P NMR and X-ray photoelectron spectroscopy data indicated that HPO4(2-) is the species present on the membrane surface. The specific concentration of acidic centers, determined ...
Hot-filament metal oxide deposition (HFMOD): a novel method for depositing thin...
Rouxinol,F. Paulo; Trasferetti,B. Cláudio; Landers,Richard; Moraes,Mário A. Bica deThis short report describes a novel method for the synthesis of metal oxide thin films. The experimental setup consists of a metal filament installed inside a vacuum chamber. The filament can be heated by an ac power supply while oxygen is admitted into the chamber using a mass flowmeter. From reactions between oxygen and the heated metal filament, volatile oxide species, Me xOy, where Me is the metal, can be f...