Materials Sciences and Applications, 2011, 2, 1302-1306 doi:10.4236/msa.2011.29176 Published Online September 2011 (http://www.SciRP.org/journal/msa) Copyright © 2011 SciRes. MSA Effect of Calcinations Temperature on Crystallography and Nanoparticles in ZnO Disk Urai Seetawan 1 , Suwit Jugsujinda 1 , Tosawat Seetawan 1* , Ackradate Ratchasin 1 , Chanipat Euvananont 2 , Chabaipon Junin 2 , Chanchana Thanachayanont 2 , Prasarn Chainaronk 3 1 Thermoelectrics Research Center, Faculty of Science and Technology, Sakon Nakhon Rajabhat University, Sakon Nakhon, Thailand; 2 National Metal and Materials Technology Center, National Science and Technology Development Agency, Pathumthani, Thailand; 3 Program of Physics, Faculty of Science, Ubonratchathani Rajabhat University, Ubon Ratchathani, Thailand. Email: * t_seetawan@snru.ac.th Received April 22 nd , 2011; revised May 30 th , 2011; accepted June 7 th , 2011. ABSTRACT We proposed a good calcinations condition of the ZnO disk to control the crystallography and nanoparticles in ZnO disk. The crystallography of precursor powder and disk powder were analyzed by the X-ray diffraction (XRD). The mean nanoparticles of ZnO disk was determinate by XRD results and observed by scanning electron microscope. The temperature ranges of 400˚C to 650˚C in air for 30 minutes were used calcinations ZnO disk. These temperature can be controlled the single phase, lattice parameters, unit cell volume, crystalline size, d-value, texture coefficient and bond lengths of Zn–Zn, Zn–O and O–O which correspond significantly the hexagonal crystal structure. The nanoparticles were small changed mean of 76.59 nm at the calcinations temperature range. Keywords: Nanoparticles in ZnO Disk, Calcinations Temperature, Crystallography of ZnO 1. Introduction Zinc oxide nanomaterials are interesting and have been developed in recent years because of their physical and chemical properties, which promote an achievement of high performance materials for various applications. Re- cently, many studies have been made in order to under- stand the microstructure, electrical properties and ther- moelectric properties of ZnO for application. For exam- ples, the varistor ceramics [1], luminescent materials [2], new coplanar gas sensor array [3], application of sun- screen nanoparticles [4] and, finally, impure ZnO materi- als are of great interest for high temperature thermoelec- tric application [5]. In this work, we report an analysis the effect of calci- nations temperature on phase identification, lattice pa- rameters, crystal structure, orientation, texture coefficient, bond length of Zn–Zn, Zn–O and O–O, powder distribu- tion and powder size in ZnO disk for control the nanopowder in ZnO disk or tendency apply the ZnO disk to thermoelectric material. 2. Experimental The ZnO precursor of nanopowder was synthesized by di- rect precipitation method using Zn(NO 3 ) 2 ·6H 2 O (QRëC TM , 98.5% purity), (NH 4 ) 2 CO 3 (QRëC TM , 99.5% purity), ethanol, and de-ionized water. Firstly, Zn(NO 3 ) 2 ·6H 2 O and (NH 4 ) 2 CO 3 were dissolved in de–ionized water by the vigorously stirring to form solutions with 1.5 and 2.25 mol/L concentrations, respectively. Secondly, the precipitates obtained by the reaction between the Zn(NO 3 ) 2 and the (NH 4 ) 2 CO 3 solutions were collected by filtration and rinsed three times with de–ionized water and ethanol, respectively, then washed and dried at 80˚C to form the precursor of nanopowder. The calcinations temperature was investigated by the relationship between the weight loss and temperature by using thermal gra- vimetric analysis (TGA–DTA/DSC; NETZSCH STA 449C). Finally, the precursor of nanopowder was pres- sured by the hydraulic press about 160 MPa in air to ob- tain the ZnO disk. The disk was calcinated at temperature range 400˚C to 650˚C in air for 30 minutes. The crystal- lography of precursor of powder and disk powder were analyzed by X–ray diffraction (XRD; PW1710) with a Cu–K1(= 0.15406 nm) source at 40 kV and 30 mA. The morphology of the precursor of powder and disk powder were observed by a scanning electron micro- scope (SEM; JSM–6100). The particle size (D) of pre- cursor and disk powder were calculated by the Debye–