Synthesis of CuAlO2 from chemically precipitated nano-sized precursors
Küçük Resim Yok
Tarih
2015
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
ELSEVIER SCI LTD
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
A study was carried out on the synthesis of CuAlO2 at temperatures below 1000 degrees C, using a simple approach based on mechanical mixing of chemically precipitated CuO and Al(OH)(3) nanoparticles. Synthesis of precursor powders was achieved at low temperatures (<100 degrees C) via precipitation from their corresponding aqueous solutions. After drying at room temperature, precursors were mixed in equimolar ratios by a combination of ball milling and sonication. Green pellets were obtained by filtration casting of the mixed powder slurry followed by dry compaction. X-ray diffraction study showed that the single phase CuAlO2 samples with high crystallinity formed only after 5 h of firing at 900 degrees C under flowing nitrogen. Electron microscopy images revealed a loosely packed microstructure with high surface area consisting of nanosized grains after the heat treatment. The achieved relative density was 45% of the theoretical density. The crystallite size was estimated to be 39 nm and the specific surface area of the sintered sample was measured as 9.67 m(2)/g. The bandgap was calculated as 3.07 eV with a transmittance of 60% in the visible region. The measured electrical conductivity was 4 x 10(-3) mS/cm at room temperature and showed an increase with increasing measurement temperature, which indicates semiconducting behavior. The conductivity was shown to increase by an order of magnitude with a higher degree of densification by sintering at 1150 degrees C. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Açıklama
Anahtar Kelimeler
Mixing, Firing, Functional applications, CuAlO2
Kaynak
CERAMICS INTERNATIONAL
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
41
Sayı
10
