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Das, Anjan
- Positron Annihilation Spectroscopic Studies of Sintering Effect on Sol–Gel-Synthesized SiO2 Wide Band Gap Semiconductor Nanocrystals
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Authors
Affiliations
1 Department of Physics, A.P.C. Roy Government College, Siliguri, Darjeeling 734 010, IN
1 Department of Physics, A.P.C. Roy Government College, Siliguri, Darjeeling 734 010, IN
Source
Current Science, Vol 117, No 12 (2019), Pagination: 1990-1998Abstract
Sol–gel procedure followed by sintering was used to prepare silica nanoparticles. Their structural properties were examined using XRD and HRTEM. Estimation of band gap and characterization of various type of defects were carried out by UV-Vis spectroscopy and positron annihilation spectroscopy. Though bulk SiO2 is an insulator, calculated band gap was in the range of wide band gap semiconductor region. High value of positron lifetime indicated presence of void type defects on sintering in air. The defect profile has changed from unsintered samples. Coincidence Doppler broadening spectroscopy revealed the momentum characteristics of core as well as valence electrons.Keywords
Band Gap, Defects, Positron Annihilation Spectroscopy, Sol–Gel Procedure, Silica Nanoparticles.Full Text
References
- Rahman Ismail, A. and Padavettan, V., Synthesis of silica nanoparticles by sol–gel: size-dependent properties, surface modification, and applications in silica–polymer nanocomposites – a review. J. Nanomater., 2012, 2012, 1–15.
- Rajendran, J., Hamid, S. S., Mohd, S. K. K., Abdullah, M. Z., Ramiah, H. and Kumar, N., An integrated linearization technique for GaAs bipolar WCDMA power amplifier. Curr. Sci., 2018, 114(2), 308–313.
- Hassan, E. M., Characterization of control mesoporous glasses (CPGs) using positron annihilation lifetime spectroscopy (PALS), Ph D thesis, Martin Luther University, Halle-Wittenberg, 2007.
- Olsen, J. V., Kirkegaard, P., Pedersen, N. J. and Eldrup, M., PALSfit: a new program for the evaluation of positron lifetime spectra. Phys. Status Solidi C, 2007, 4, 4004–4006.
- Chatterjee, A., Ramachandran, K., Kumar, A. and Behere, A., Linux Advanced MultiParameter System. Trombay, Mumbai; http://www.tifr.res.in/~pell/lamps.html (accessed on July 2015).
- Cullity, B. D., Elements of X-ray Diffraction, Addison-Wesley, Massachusetts, USA, 1956.
- Buscarino, G., Ardizzone, V., Vaccaro, G. and Gelardi, F. M., Sintering process of amorphous SiO2 nanoparticles investigated by AFM, IR and Raman techniques. J. Non-Crystalline Solids, 2011, 357, 1866–1870.
- Diehm P. M., Agoston, P. and Albe, K., Size-dependent lattice expansion in nanoparticles: reality or anomaly? ChemPhysChem, 2012, 13, 2443–2454.
- Dutta, S., Chattopadhyay, S., Sarkar, A., Chakrabarti, M., Sanyal, D. and Jana, D., Role of defects in tailoring structural, electrical and optical properties of ZnO. Prog. Mater. Sci., 2009, 54, 89–95.
- Rahman, I. A., Vejayakumaran, P., Sipaut, C. S., Ismail, J. and Chee, C. K., Size-dependent physicochemical and optical properties of silica nanoparticles. Mater. Chem. Phys., 2009, 114, 328– 332.
- Ghislottia, G., Nielsen, B., Asoka-Kumar, P., Lynn, K. G., Di Mauro, L. F., Corni, F. and Tonini, R., Positron annihilation studies of silicon-rich SiO2 produced by high dose ion implantation. Appl. Phys. Lett., 1997, 70(4), 496–498.
- Siegel, R. W., Positron annihilation spectroscopy. Ann. Rev. Mater. Sci., 1980, 10, 393–425.
- Jan, W., Jacek, G., Radoslaw, Z. and Tomasz, G., Positron lifetime in mesoporous silica of MCM-41 type. Langmuir, 2003, 19(7), 2599–2605.
- Kuriplach, J. and Barbiellini, B., Gradient correction scheme for bulk and defect positron states in materials: new developments. J. Physics: Conf. Ser., 2014, 505, 012040–012048.
- Rajesh, P., Sellaiyan, S., Uedono, A., Arun, T. and Joseyphus, R. J., Positron annihilation studies on chemically synthesized FeCo alloy. Nature, 2018, 8:9764, 1–9.
- Das, A., Mandal, A. C. and Nambissan, P. M. G., Effect of size on momentum distribution of electrons around vacancies in NiO nanoparticles. Chin. Phys. B, 2015, 24(4), 046102–046104.
- Amarendra, G., Viswanathan, B., Rao, V. G., Parimala, J. and Purniah, B., Variable low energy positron beams for depth resolved defect spectroscopy in thin film structures. Curr. Sci., 1997, 73(5), 409–417.