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In this paper, a simple and cheap method to prepare porous ZnO by using zinc nitrate, ethanol and triethanolamine (TEA) is reported. The as-prepared sample consisted of nano and micro pores. The sample was calcined at 300 ℃, 400 ℃ and 500 ℃ with different heating rates. At 500 ℃, the nano pores disappeared but the sample maintained its micro porosity. Field emission scanning electron microscopy (FE-SEM) pictures confirmed that the size and growth of ZnO nanoparticles depended on the heating conditions. The infrared (IR) absorption peak of Zn–O stretching vibration positioned at 457 cm-1 was split into two peaks centered at 518 cm-1 and 682 cm-1 with the change of morphology. These results confirmed that Fourier transform infrared (FT-IR) spectrum was sensitive to variations in particle size, shape and morphology. The photoluminescence (PL) spectrum of porous ZnO contained five emission peaks at 397 nm, 437 nm, 466 nm, 492 nm and 527 nm. Emission intensity enhanced monotonously with increase of temperature and the change was rapid between temperatures of 300 ℃ and 500 ℃. This was due to the elimination of organic species and improvement in the crystallanity of the sample at 500 ℃.


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Synthesis and optical characterization of porous ZnO

Show Author's information K. SOWRI BABU*( )A. RAMACHANDRA REDDYCh. SUJATHAK. VENUGOPAL REDDYA. N. MALLIKA
Department of Physics, National Institute of Technology Warangal, Warangal-506 004, Andhra Pradesh, India

Abstract

In this paper, a simple and cheap method to prepare porous ZnO by using zinc nitrate, ethanol and triethanolamine (TEA) is reported. The as-prepared sample consisted of nano and micro pores. The sample was calcined at 300 ℃, 400 ℃ and 500 ℃ with different heating rates. At 500 ℃, the nano pores disappeared but the sample maintained its micro porosity. Field emission scanning electron microscopy (FE-SEM) pictures confirmed that the size and growth of ZnO nanoparticles depended on the heating conditions. The infrared (IR) absorption peak of Zn–O stretching vibration positioned at 457 cm-1 was split into two peaks centered at 518 cm-1 and 682 cm-1 with the change of morphology. These results confirmed that Fourier transform infrared (FT-IR) spectrum was sensitive to variations in particle size, shape and morphology. The photoluminescence (PL) spectrum of porous ZnO contained five emission peaks at 397 nm, 437 nm, 466 nm, 492 nm and 527 nm. Emission intensity enhanced monotonously with increase of temperature and the change was rapid between temperatures of 300 ℃ and 500 ℃. This was due to the elimination of organic species and improvement in the crystallanity of the sample at 500 ℃.

Keywords: optical properties, semiconductors, porous ZnO

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Publication history

Received: 18 March 2013
Revised: 19 April 2013
Accepted: 03 May 2013
Published: 07 September 2013
Issue date: September 2013

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© The author(s) 2013

Acknowledgements

The authors thank the dean of School of Physics, University of Hyderabad, for providing FE-SEM facility generously, and are also grateful to Y. B. Ravi Shankar for his continuous support in XRD analysis of the samples.

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Open Access: This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

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