Int. J. Mol. Sci. 2012, 13(4), 5278-5289; doi:10.3390/ijms13045278
Article

Synthesis Mechanism of Low-Voltage Praseodymium Oxide Doped Zinc Oxide Varistor Ceramics Prepared Through Modified Citrate Gel Coating

Received: 20 February 2012; in revised form: 31 March 2012 / Accepted: 12 April 2012 / Published: 24 April 2012
(This article belongs to the Section Material Sciences and Nanotechnology)
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract: High demands on low-voltage electronics have increased the need for zinc oxide (ZnO) varistors with fast response, highly non-linear current-voltage characteristics and energy absorption capabilities at low breakdown voltage. However, trade-off between breakdown voltage and grain size poses a critical bottle-neck in the production of low-voltage varistors. The present study highlights the synthesis mechanism for obtaining praseodymium oxide (Pr6O11) based ZnO varistor ceramics having breakdown voltages of 2.8 to 13.3 V/mm through employment of direct modified citrate gel coating technique. Precursor powder and its ceramics were examined by means of TG/DTG, FTIR, XRD and FESEM analyses. The electrical properties as a function of Pr6O11 addition were analyzed on the basis of I-V characteristic measurement. The breakdown voltage could be adjusted from 0.01 to 0.06 V per grain boundary by controlling the amount of Pr6O11 from 0.2 to 0.8 mol%, without alteration of the grain size. The non-linearity coefficient, α, varied from 3.0 to 3.5 and the barrier height ranged from 0.56 to 0.64 eV. Breakdown voltage and α lowering with increasing Pr6O11 content were associated to reduction in the barrier height caused by variation in O vacancies at grain boundary.
Keywords: citrate gel; praseodymium oxide; varistors; zinc oxide
PDF Full-text Download PDF Full-Text [1058 KB, uploaded 19 June 2014 04:16 CEST]

Export to BibTeX |
EndNote


MDPI and ACS Style

Wan Abdullah, W.R.; Zakaria, A.; Ghazali, M.S.M. Synthesis Mechanism of Low-Voltage Praseodymium Oxide Doped Zinc Oxide Varistor Ceramics Prepared Through Modified Citrate Gel Coating. Int. J. Mol. Sci. 2012, 13, 5278-5289.

AMA Style

Wan Abdullah WR, Zakaria A, Ghazali MSM. Synthesis Mechanism of Low-Voltage Praseodymium Oxide Doped Zinc Oxide Varistor Ceramics Prepared Through Modified Citrate Gel Coating. International Journal of Molecular Sciences. 2012; 13(4):5278-5289.

Chicago/Turabian Style

Wan Abdullah, Wan Rafizah; Zakaria, Azmi; Ghazali, Mohd Sabri Mohd. 2012. "Synthesis Mechanism of Low-Voltage Praseodymium Oxide Doped Zinc Oxide Varistor Ceramics Prepared Through Modified Citrate Gel Coating." Int. J. Mol. Sci. 13, no. 4: 5278-5289.

Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert