Porous Tin Oxide Nanostructured Microspheres for Sensor Applications

Martínez, Carlos; Hockey, B. J.; Montgomery, Christopher B.; Semancik, Steve

doi:10.1021/la050118z

Cited by 244 publications

(137 citation statements)

References 22 publications

Supporting

Mentioning

137

Contrasting

Order By: Relevance

“…It has already been reported [52,53] that, the SnO2 sensitivity increases with respect to the porosity with different additives. An increment in the surface porosity will increase the active surface area which allows the sensing gas to diffuse into the pellet pores [54]. To observe the pellet surface porosity, powders obtained by chemically doped Cu: SnO2 were observed in SEM at a lower magnification and the results are shown in Figure 6.…”

Section: Sem Analysismentioning

confidence: 99%

An Elaborated Study of CO Sensitivities of Cu, Pt and Pd Activated SnO<sub>2</sub> Sensors: Effect of Precipitation Agents, Dopants and Doping Methods

Karthik¹,

Gómez-Pozos²,

Rodríguez-Lugo³

et al. 2017

Preprint

View full text Add to dashboard Cite

Abstract:In this work, we report synthesis of Cu, Pt and Pd doped SnO2 powders and their comparative CO gas sensing studies. Dopants were incorporated into SnO2 nanostructures using chemical and impregnation methods by using urea and ammonia as precipitation agents. The synthesized samples were characterized using X-ray diffraction (XRD), Raman spectroscopy, Scanning electron microscopy (SEM) and High resolution transmission electron microscopy (HR-TEM). The presence of dopants within the SnO2 nanostructures was evidenced from HR-TEM. Doped powders utilizing chemical methods with urea as precipitation agent presented higher sensitivities compared to the remaining, which is due to the formation of uniform and homogeneous particles resulted from the temperature assisted synthesis. The particle sizes of doped SnO2 nanostructures were in the range of 40-100 nm. An enhanced sensitivity around 1783 was achieved with Cu doped SnO2 when compared with two other dopants i.e., Pt (1200) and Pd: SnO2(502). The high sensitivity of Cu: SnO2 is due to formation of CuO and its excellent association and dissociation in the presence of CO with adsorbed atmospheric oxygen at sensor operation temperatures resulted in high conductance. Cu: SnO2 may be an alternative and cost effective sensor for industrial applications.

show abstract

Section: Sem Analysismentioning

confidence: 99%

An Elaborated Study of CO Sensitivities of Cu, Pt and Pd Activated SnO<sub>2</sub> Sensors: Effect of Precipitation Agents, Dopants and Doping Methods

Karthik¹,

Gómez-Pozos²,

Rodríguez-Lugo³

et al. 2017

Preprint

View full text Add to dashboard Cite

show abstract

“…Concentration of the PSS was held at 0.75 wt.%. The surface-functionalized polymer beads were then filtered through a membrane and were re-dispersed in solvent mixtures consisting of water, ethanol, and reagent-grade tetraethyl orthosilicate (TEOS, Si(OC 2 H 5 ) 4 , Aldrich, U.S.A.) with a molar ratio of 4:4:1. The colloidal mixtures were placed in a temperature-controlled water bath kept at 60°C for 2 h with continuous agitations.…”

Section: Preparation Of Hollow Silica Particlesmentioning

confidence: 99%

Electrophoretic movement of hollow silica particles under DC electric fields

Tseng

Tsai

Lin

2010

J. Ceram. Soc. Japan

View full text Add to dashboard Cite

The electrophoretic movement of colloidal silica particles with hollow interior and nanoporous shell structure was examined under a homogeneous direct current (DC) electric field as a function of field strengths (50150 V) and solution pHs (410). The electrophoretic behavior was compared with that of solid silica particles of similar size. In an acidic solution (pH~4) at which the solution pH near the PZC (pH~2), mobility of the hollow particles appeared to be insensitive to the change of applied voltage in a dilute solids concentration. As pH moved away from the PZC to a basic solution (pH~10), velocity of the charged particles increased pronouncedly and the velocity was in a linear proportion with the DC field strength, suggesting that the particles were moved by electrophoresis. The hollow silica particles yet showed a much slower electrophoretic velocity, less than one half, than that of the solid counterparts at the alkaline situation (pH~10). This lagged motion was due presumably to the rough outer surface and the permeable shell structure (pore radius~20 nm), both contributing to the hydrodynamic friction that retards the electrophoretic movement.

show abstract

“…[2][3][4][5][6] In engineering, these concepts are widely used for drug delivery, 7 optical devices, 8 and sensors. 9 Especially, when a structure with a volumeshrinking effect is used as an inclusion in a composite structure, a series of special material properties could be achieved. 10,11 One of the seminal studies is the Lakes's theoretical analysis of a conceptual composite with extreme damping and a negative Poisson's ratio (NPR).…”

Section: Introductionmentioning

confidence: 99%

Tailoring structure of inclusion with strain-induced closure to reduce Poisson's ratio of composite materials

Hou

Silberschmidt

2014

Journal of Applied Physics

View full text Add to dashboard Cite

Tailoring structure of inclusion with strain-induced closure to reduce Poisson's ratio of composite materials A novel 3D continuum shell structure is introduced as inclusion for composite materials with special mechanical properties in this paper. Its geometry is based on a hollow re-entrant tetrahedron. In a composite, such an inclusion can demonstrate a closure effect induced by external compression. Its specific deformation mechanism results in a special character of deformation and affects effective (global) mechanical properties of the composite. A finite-element method is used to explore quantitatively and qualitatively the deformation mechanism of the suggested inclusion and its effect on the overall mechanical performance of the composite. In this study, geometrical features of the inclusion are used as parameters. The obtained results demonstrate that this kind of inclusion could reduce the composite's Poisson's ratio; moreover, its magnitude is adjustable by changing geometrical parameters of the inclusion. Besides, an overall hardening effect is achieved for the composite, with the magnitude of global stiffness also significantly affected by geometrical features of the inclusion. Thus, the developed inclusion actually provides a potential to develop new composites with a tunable Poisson's ratio and enhanced mechanical properties .V

show abstract

Porous Tin Oxide Nanostructured Microspheres for Sensor Applications

Cited by 244 publications

References 22 publications

An Elaborated Study of CO Sensitivities of Cu, Pt and Pd Activated SnO<sub>2</sub> Sensors: Effect of Precipitation Agents, Dopants and Doping Methods

An Elaborated Study of CO Sensitivities of Cu, Pt and Pd Activated SnO<sub>2</sub> Sensors: Effect of Precipitation Agents, Dopants and Doping Methods

Electrophoretic movement of hollow silica particles under DC electric fields

Tailoring structure of inclusion with strain-induced closure to reduce Poisson's ratio of composite materials

Contact Info

Product

Resources

About