Optical and electrical properties of carbon nanotube-containing Se₈₅Te₁₀Ag₅ glassy composites

Abstract

The infrared optical transmission spectra of 3 and 5 wt.% of carbon nanotube (CNT)-containing Se₈₅Te₁₀Ag₅ glassy composites were recorded in the mid-IR region from 4000  to 400 cm⁻¹ using Fourier transform infrared spectroscopy (FTIR). The FTIR spectra manifested functional groups interacting the CNT surface and the Se₈₅Te₁₀Ag₅ glassy matrix. Photoluminescence (PL) spectra of the CNT-containing Se₈₅Te₁₀Ag₅ glassy composites exhibited PL emission peaks centred within the range 715–725 nm. The optical absorption spectra differed between pure Se₈₅Te₁₀Ag₅ glass and the CNT-containing Se₈₅Te₁₀Ag₅ glassy composites. The electrical conductivity of CNT-containing Se₈₅Te₁₀Ag₅ glassy composites was enhanced by four orders of magnitude with the CNT additive. This can be attributed to the formation of many conductive paths through the CNT–CNT internanotube percolation network.

Keywords:

• Carbon nanotube
• photoluminescence
• emission spectra
• absorption coefficient
• percolation network
• SeTeAg glass

Acknowledgements

The authors are grateful to Prof S.B. Rai for his kind help in PL characterisation. We thank Dr K. Asokan and Dr P.K. Kulriya at IUAC New Delhi for electrical measurements and the Department of Chemistry, Banaras Hindu University, Varanasi for FTIR and UV/VIS/NIR characterisations.