Dielectric dispersion in the PbO–MoO3–B2O3 glass system

Prasad, P. Syam; Raghavaiah, B.V.; Rao, R. Prasada; Laxmikanth, C.; Veeraiah, N.

doi:10.1016/j.ssc.2004.07.042

Cited by 59 publications

(19 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…W + 6 ions act as modifiers, weaken the glass network and ,thus create pathways suitable for migration of free ions that build up space charge. Thus, the weaker the network the much more is the space charge polarization which leads to an increase in the dielectric constants values [10,28]. This conclusion is further supported by the results that with increasing WO 3 content in alkali phosphate glasses, the degree of deformation of glass network will increase bonding defects, which in turn increase the space charge polarization causing an increase in the values of dielectric parameters [7,31].…”

Section: The Dielectric Constant ε \ and The Dielectric Loss Tan δmentioning

confidence: 59%

See 1 more Smart Citation

Dielectric properties and scaling behavior of lithium tungsten phosphate glasses

Shaaban

2012

J Electroceram

View full text Add to dashboard Cite

In the present study a series of ternary (30 Li 2 O, (70-x) P 2 O 5 , xWO3) glasses were prepared and their dielectric properties and ac conductivity were investigated. The measurements have been taken in the frequency range from 100 Hz to 100 kHz and over the temperature range from 296 K to 578 K. The temperature dependence of ac conductivity can be adequately explained by considering the contributions from mixed ionic and electronic mechanisms. In the studied glasses it is found that the ac conductivity increases with increasing frequency. By investigating the relation between temperature and the frequency exponent "s" of the power law σ ac 0Aω s , it is found that the Correlated Barrier Hopping model (CBH) is appropriate for describing the conduction mechanism in the samples. In an attempt to investigate the universality of ac conductivity in these glasses, it is found that the data obtained follow Rolling scaling model. When considering the dielectric properties, it is found that the M″vs. M′ plots give master ColeCole curves at all temperatures. These results can be considered as an indication of the presence of space charge or accumulation of charges in some regions inside the samples. The relation between M″/ M max″ and f/f p represent a master plot at different temperatures. These scaling suggest the existence of a distribution of potential wells, in which the carriers are trapped.

show abstract

Section: The Dielectric Constant ε \ and The Dielectric Loss Tan δmentioning

confidence: 59%

“…5(a). Prasad et, al [28] studied the dielectric properties of PbO borate glass containing MoO 3 . They reported that the considerable increase of dielectric constant values with temperature can be attributed to the space charge polarization associated with bonding defects [29].…”

Section: The Dielectric Constant ε \ and The Dielectric Loss Tan δmentioning

confidence: 99%

Dielectric properties and scaling behavior of lithium tungsten phosphate glasses

Shaaban

2012

J Electroceram

View full text Add to dashboard Cite

show abstract

“…The spectrum of MoO 3 free glasses does not exhibit any absorption band. But small amount of molybdenum is added to glasses matrix shows a broad optical absorption band at about 681 nm 15 . The intensity of this band was observed to increase gradually as the concentration of MoO 3 increased.…”

Section: Absorption Spectramentioning

confidence: 99%

Effects of MoO<SUB>3</SUB> Addition on Spectroscopic Properties of Lithium Zinc Borate Glass

Rao¹,

Cole²,

Prasad³

2013

View full text Add to dashboard Cite

The paper deals with the spectroscopic properties of Li 2 O -ZnO-B 2 O 3 glass containing different concentrations of MoO 3 (ranging from 1 to 5 mol %) were prepared by melt quenching. Spectroscopic (infrared, optical absorption spectra and ESR) properties of these glasses have been carried out. The Optical absorption Spectrum contains one broad absorption band at 681 nm, this attributed to the excitation of Mo 5+ (4d 1 ) ion. ESR studies reveal Molybdenum ions are expected to exist mainly in the Mo 6+ state in the glass network. As the concentration of MoO 3 is increased, especially beyond 5.0 mol %, the colour of the glasses increased, that indicating the reduction of molybdenum ions from the Mo 6+ state to the Mo 5+ state. ESR, IR and Optical absorption spectra of paramagnetic ion in the above glasses reveal that the site symmetry of the transition metal ion is elongated octahedral.

show abstract

“…Molybdenum ions in the glasses have been the subject of many investigations due to their catalytic properties. Interesting studies are available on the environment of molybdenum ion in different inorganic glasses [8][9][10][11][12][13]. Mo-O bond in molybdenum hexavalent oxide is identified as significantly covalent.…”

mentioning

confidence: 99%

SPECTROSCOPIC PROPERTIES OF LITHIUM SODIUM BORATE GLASS BY THE ADDITION OF MoO3.

Sugathri.¹,

Rao²

2017

IJAR

View full text Add to dashboard Cite

1 mol %) were prepared by melt quenching are studied. Spectroscopic (XRD, infrared, optical absorption spectra and EPR) properties of these glasses have been carried out. As the concentration of MoO 3 is increased especially beyond 0.4 mol %, the colour of the glasses increased, which is indicating the reduction of molybdenum ions from …………………………………………………………………………………………………….... Introduction:-The glasses containing transition metal ions came into prominence because of their notable spectroscopic properties and their suitability for fibre optic communications, luminescent solar energy concentrators (LSC) [1].Among the many glasses, borate glasses have been known to be excellent host materials for transition metal oxides because of their glass forming nature compared to other conventional glass systems. Borate glasses are used as wave-guides, electro-optic switches, electro-optic modulators, magneto-optic materials, solid-state laser materials and non-linear optical parametric converters [2][3][4]. In addition, they are often used as dielectric and insulating materials and it is known that borate glass constitute a good shield against IR radiation [5]. In general B 2 O 3 glasses have a property of showing minimum expansion due to the large amount of boric oxide which is of great importance in obtaining thermal durability. It also decreases the tendency for glass to devitrify or crystallize. B 2 O 3 is a basic glass former because of its higher bond strength, lower cation size and smaller heat of fusion. The ions of molybdenum introduce high activity and selectivity in a series of oxidation reactions of practical importance in the glass matrices [6,7].Molybdenum oxide belongs to the intermediate class of glass forming oxides. It does not readily form the glass but does so in the presence of the modifier with MoO 4 . Molybdenum ions in the glasses have been the subject of many investigations due to their catalytic properties. Interesting studies are available on the environment of molybdenum ion in different inorganic glasses [8][9][10][11][12][13]. Mo-O bond in molybdenum hexavalent oxide is identified as significantly covalent. The Mo ion exist a stable valence state viz., MoV and MoVI in the glass network. Molybdenum ions act both as network formers as well as network modifiers depending upon their concentration and nature of the host network.Mo−O bond in molybdenum hexavalent oxide is identified as covalent. The Mo ion exists at least in two

show abstract

Dielectric dispersion in the PbO–MoO3–B2O3 glass system

Cited by 59 publications

References 22 publications

Dielectric properties and scaling behavior of lithium tungsten phosphate glasses

Dielectric properties and scaling behavior of lithium tungsten phosphate glasses

Effects of MoO<SUB>3</SUB> Addition on Spectroscopic Properties of Lithium Zinc Borate Glass

SPECTROSCOPIC PROPERTIES OF LITHIUM SODIUM BORATE GLASS BY THE ADDITION OF MoO3.

Contact Info

Product

Resources

About