Limits...
Agricultural wastes as a resource of raw materials for developing low-dielectric glass-ceramics.

Danewalia SS, Sharma G, Thakur S, Singh K - Sci Rep (2016)

Bottom Line: Sugarcane leaves ash exhibits higher content of alkali metal oxides than rice husk ash, which reduces the melting point of the components due to eutectic reactions.The presence of less ordered augite phase enhances the dielectric permittivity as compared to cristobalite and tridymite phases.The glass-ceramics developed with adequately devitrified phases can be used in microelectronic devices and other dielectric applications.

View Article: PubMed Central - PubMed

Affiliation: School of Physics and Materials Science, Thapar University, Patiala-147004, India.

ABSTRACT
Agricultural waste ashes are used as resource materials to synthesize new glass and glass-ceramics. The as-prepared materials are characterized using various techniques for their structural and dielectric properties to check their suitability in microelectronic applications. Sugarcane leaves ash exhibits higher content of alkali metal oxides than rice husk ash, which reduces the melting point of the components due to eutectic reactions. The addition of sugarcane leaves ash in rice husk ash promotes the glass formation. Additionally, it prevents the cristobalite phase formation. These materials are inherently porous, which is responsible for low dielectric permittivity i.e. 9 to 40. The presence of less ordered augite phase enhances the dielectric permittivity as compared to cristobalite and tridymite phases. The present glass-ceramics exhibit lower losses than similar materials synthesized using conventional minerals. The dielectric permittivity is independent to a wide range of temperature and frequency. The glass-ceramics developed with adequately devitrified phases can be used in microelectronic devices and other dielectric applications.

No MeSH data available.


Related in: MedlinePlus

FTIR spectra of the quenched samples derived from agricultural waste ash.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4834533&req=5

f3: FTIR spectra of the quenched samples derived from agricultural waste ash.

Mentions: Infrared transmittance spectra of all the as-quenched samples are presented in Fig. 3. The observed transmittance spectra of the present glasses and glass-ceramics can be explained as follows: (a) The broad band at 1080 cm−1 can be attributed to the Si-O-Si asymmetric stretching vibrations in the SiO4 units. Broadness of the band is due to the superposition of the IR-bands of the asymmetric vibrations of different type of Q-units of silica network. Q4 and Q3 units give rise to vibration bands at ~1100–1150 cm−1 and ~1050–1100 cm−1, respectively. Centre of the band at ~1080 cm−1 indicates abundance of SiO4 units with four and three bridging oxygen atoms2324. The IR-band at ~794 cm−1 is due to the symmetric stretching of the Si-O-Si bonds of the SiO4 tetrahedra. (b) The bands around 475 cm−1 are mainly due to the Si-O bending vibrations2526. The bending vibrations of Al-O bonds also occur within this wavenumber range27. (c) The band around 620 cm−1, which is present only in R-75 and R-100 glass-ceramics, is the characteristic band of cristobalite26. The presence of this band, only in these samples, is also well supported by XRD results, which clearly indicates the presence of cristobalite phase in both the glass-ceramics. This band becomes sharp and more intense in R-100 as compared to R-75, which indicates the higher volume fraction of cristobalite phase. (d) IR band at ~565 cm−1 corresponds to stretching vibrations of Si-O-Al molecules28. The observed bands exhibit a red shift for all the samples. It can be attributed to the weakening of the structural units due to increase in the NBOs2930.


Agricultural wastes as a resource of raw materials for developing low-dielectric glass-ceramics.

Danewalia SS, Sharma G, Thakur S, Singh K - Sci Rep (2016)

FTIR spectra of the quenched samples derived from agricultural waste ash.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4834533&req=5

f3: FTIR spectra of the quenched samples derived from agricultural waste ash.
Mentions: Infrared transmittance spectra of all the as-quenched samples are presented in Fig. 3. The observed transmittance spectra of the present glasses and glass-ceramics can be explained as follows: (a) The broad band at 1080 cm−1 can be attributed to the Si-O-Si asymmetric stretching vibrations in the SiO4 units. Broadness of the band is due to the superposition of the IR-bands of the asymmetric vibrations of different type of Q-units of silica network. Q4 and Q3 units give rise to vibration bands at ~1100–1150 cm−1 and ~1050–1100 cm−1, respectively. Centre of the band at ~1080 cm−1 indicates abundance of SiO4 units with four and three bridging oxygen atoms2324. The IR-band at ~794 cm−1 is due to the symmetric stretching of the Si-O-Si bonds of the SiO4 tetrahedra. (b) The bands around 475 cm−1 are mainly due to the Si-O bending vibrations2526. The bending vibrations of Al-O bonds also occur within this wavenumber range27. (c) The band around 620 cm−1, which is present only in R-75 and R-100 glass-ceramics, is the characteristic band of cristobalite26. The presence of this band, only in these samples, is also well supported by XRD results, which clearly indicates the presence of cristobalite phase in both the glass-ceramics. This band becomes sharp and more intense in R-100 as compared to R-75, which indicates the higher volume fraction of cristobalite phase. (d) IR band at ~565 cm−1 corresponds to stretching vibrations of Si-O-Al molecules28. The observed bands exhibit a red shift for all the samples. It can be attributed to the weakening of the structural units due to increase in the NBOs2930.

Bottom Line: Sugarcane leaves ash exhibits higher content of alkali metal oxides than rice husk ash, which reduces the melting point of the components due to eutectic reactions.The presence of less ordered augite phase enhances the dielectric permittivity as compared to cristobalite and tridymite phases.The glass-ceramics developed with adequately devitrified phases can be used in microelectronic devices and other dielectric applications.

View Article: PubMed Central - PubMed

Affiliation: School of Physics and Materials Science, Thapar University, Patiala-147004, India.

ABSTRACT
Agricultural waste ashes are used as resource materials to synthesize new glass and glass-ceramics. The as-prepared materials are characterized using various techniques for their structural and dielectric properties to check their suitability in microelectronic applications. Sugarcane leaves ash exhibits higher content of alkali metal oxides than rice husk ash, which reduces the melting point of the components due to eutectic reactions. The addition of sugarcane leaves ash in rice husk ash promotes the glass formation. Additionally, it prevents the cristobalite phase formation. These materials are inherently porous, which is responsible for low dielectric permittivity i.e. 9 to 40. The presence of less ordered augite phase enhances the dielectric permittivity as compared to cristobalite and tridymite phases. The present glass-ceramics exhibit lower losses than similar materials synthesized using conventional minerals. The dielectric permittivity is independent to a wide range of temperature and frequency. The glass-ceramics developed with adequately devitrified phases can be used in microelectronic devices and other dielectric applications.

No MeSH data available.


Related in: MedlinePlus