Micro-Raman studies of swift heavy ion irradiation induced structural and conformational changes in polyaniline nanofibers

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 268; no. 17; pp. 2683 - 2687
• Main Authors: Banerjee, Somik, Kumar, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2010
• Subjects: Amorphization; Angle of reflection; Beam interactions; Benzenoids; Fluence; Irradiation; Micro-Raman spectroscopy; Nanofibers; PAni nanofibers; Polyanilines; Swift heavy ions; TEM; Transmission electron microscopy; XRD; PAni nanofibers; Swift heavy ions; XRD; TEM; Micro-Raman spectroscopy
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2010.06.003

Polyaniline (PAni) nanofibers doped with camphor sulfonic acid have been irradiated with 90 MeV O 7+ ions at different fluences (3 × 10 10−1 × 10 12 ions/cm 2) using a 15UD Pelletron accelerator under ultra-high vacuum. XRD studies reveal a decrease in the domain length and an increase in the strain upon SHI irradiation. The increase in d-spacing corresponding to the (1 0 0) reflection of PAni nanofibers with increasing irradiation fluence has been attributed to the increase in the tilt angle of the chains with respect to the ( a, b ) basal plane of PAni. Decrease in the integral intensity upon SHI irradiation indicates amorphization of the material. Micro-Raman (μR) studies confirm amorphization of the PAni nanofibers and also show that the PAni nanofibers get de-doped upon SHI irradiation. μR spectroscopy also reveals a benzenoid to quinoid transition in the PAni chain upon SHI irradiation. TEM results show that the size of PAni nanofibers decreases with the increase in irradiation fluence, which has been attributed to the fragmentation of PAni nanofibers in the core of amorphized tracks caused by SHI irradiation.