Stabilization of intrinsic defects at high temperatures in ZnO nanoparticles by Ag modification.
The stabilization of defects in ZnO at high temperatures has been investigated. The properties of unmodified and modified ZnO nanoparticles (NPs) with 2 at.% of Ag prepared by microwave assisted combustion method, have been systematically studied using X-ray diffraction (XRD), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS) and photocatalytic activity measurements. Though the XRD data shows a marginal shift in the ZnO peak position upon Ag addition, the amount of shift does not change with annealing temperatures. The PL data reveals that the defect mediated visible emission intensity of unmodified ZnO NPs increases with increase in the annealing temperature, whereas it remains almost unchanged in Ag-ZnO. This study clearly establishes that silver is an efficient stabilizer of intrinsic defects in ZnO at high temperatures. This is further supported by the core and valence band XPS spectra.
CSIR-National Metallurgical Laboratory, Jamshedpur 831 007, India. Electronic address: rksahu@nmlindia.org.
Ranjan K
RK
Sahu
Department of Metallurgical and Materials Engineering, IIT, Kharagpur 721 302, India.
K
K
Ganguly
CSIR-National Metallurgical Laboratory, Jamshedpur 831 007, India.
T
T
Mishra
CSIR-National Metallurgical Laboratory, Jamshedpur 831 007, India.
M
M
Mishra
Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
R S
RS
Ningthoujam
Department of Metallurgical and Materials Engineering, IIT, Kharagpur 721 302, India.
S K
SK
Roy
CSIR-National Metallurgical Laboratory, Jamshedpur 831 007, India.
L C
LC
Pathak