Physical ageing in Se-Te-Sb glasses

Title

Physical ageing in Se-Te-Sb glasses

Creator

Vanitha M.K.; Hanumantha Rao M.V.; Asokan S.; Ramesh K.

Description

Bulk Se60-xTe40Sbx glasses in the composition range 0?x?14 were prepared by the melt quenching method. Differential Scanning Calorimetric (DSC) and thermal crystallization studies were performed to understand the thermodynamic property like glass transition and structural transformations. These glasses exhibit sharp endothermic peak at the glass transition (Tg). Disappearance of the endothermic peak at Tg in the rejuvenated samples clearly indicates the ageing effect in these glasses. Addition of Sb to Se-Te increases the connectivity of the structural network which is evidenced from the increase in Tg. A distinct change in the slope of the Tg at x=6, indicates a major change in the way the network is connected. The glass forming ability and the thermal stability also exhibit a maximum at x=6. Tg increases with the ageing time and the corresponding fictive temperature (Tf) calculated from the specific heat curves shows a decreasing trend. The molecular movements along the polymeric Se chains might cause the structural relaxation and the physical ageing. The physical ageing effect has been understood on the basis of the Bond Free Solid Angle (BFSA) model proposed by Kastner. Thermally crystallized samples show the formation of rhombohedral Sb2Te 3, rhombohedral Sb2Se3 and hexagonal Te phases. 2013 Elsevier Ltd.

Source

Journal of Physics and Chemistry of Solids, Vol-74, No. 6, pp. 804-810.

Date

2013-01-01

Subject

A. Chalcogenides; A. Glasses; C. Differential Scanning Calorimetry (DSC); D. Specific heat; D. Thermodynamic properties

Coverage

Vanitha M.K., Department of Physics, Christ University, Bangalore 560029, India; Hanumantha Rao M.V., Department of Physics, Christ University, Bangalore 560029, India, LEOS, Indian Space Research Organization, Bangalore 560058, India; Asokan S., Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012, India; Ramesh K., Department of Physics, Indian Institute of Science, Bangalore 560012, India

Rights

Restricted Access

Relation

ISSN: 223697; CODEN: JPCSA

Format

Online

Language

English

Type

Article

Identifier

https://doi.org/10.1016/j.jpcs.2013.01.010

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84875232114&doi=10.1016%2fj.jpcs.2013.01.010&partnerID=40&md5=a7330f61754179ea845d5d276a41e69b