Polycrystalline MgxZn1-xO (MZO) thin films on glass substrates were prepared by sol-gel method. All the films retained the hexagonal wurtzite structure of ZnO. The band gap values determined from transmission spectra were found to be smaller than the values obtained from Vegard's law for the as-deposited MZO films. For the films with x = 0.1, 0.2 and 0.3, the band gap blue-shifted initially and then red-shifted with increase in the annealing temperature. The reason for this anomalous shift in the band gap is attributed to the proper substitution of Mg atoms into the Zn lattice sites after a certain critical annealing temperature. © Springer Science+Business Media, LLC 2009.

Mahaveer Kumar Jain

Department Of Physics

Annealing temperatures

BAND-GAP VALUES

Glass substrates

Hexagonal wurtzite structure

MgZnO

Nanocrystallines

Polycrystalline

Transmission spectrums

Annealing

Energy gap

Sol-gel process

Sol-gels

Substrates

Thin films

Zinc

Zinc sulfide

Film preparation

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IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Journal of Sol-Gel Science and Technology

Composite metal oxide based thin film based sensors are proposed to eradicate the problems faced by the single phase materials. The composite thin films of ZnO and SnO2 are expected to have significantly enhanced humidity sensing properties. In the present work, pure and composite thin films of ZnO and SnO2 are prepared by sol-gel based spin coating. The structural, optical and morphological properties of the films were studied by X-ray diffraction, Ultraviolet-Visible absorption spectroscopy and the scanning electron microscopy. The composite films with different compositions of ZnO and SnO2 phase were studied for their impedometric humidity sensing characteristics. Among the proposed sensors, the zinc rich composite sensors exhibit the maximum sensor response of 95% and sensitivity of 8.6 ± 0.5 kΩ/RH%. Further, the composite metal oxide based humidity sensors exhibit better transient characteristics and significantly lower hysteresis compared to their pure counterparts. © 2019 Elsevier B.V.

Sensors and Actuators B: Chemical

Composite metal oxide thin film based impedometric humidity sensors

In the present work, anatase TiO2 films are prepared by sol-gel spin coating method. The structural and optical properties of the films have been studied at different post-annealing temperatures. The photocatalytic activity and electrochromic performance of the films are investigated. The films annealed at 400 °C exhibit the highest photocatalytic activity with a rate constant of 4.56×10-3 min-1. The electrochromic performance for the films annealed at 400 °C expressed in terms of difference in optical density (ΔOD) at 550 nm between coloured and bleached state is 0.5493. This combination of photocatalysis and electrochromism makes the sol-gel derived titania thin films as promising candidates for self-cleaning smart window applications. © 2014 Elsevier Ltd.

Materials Science in Semiconductor Processing

Sol–gel derived nanocrystalline TiO2 thin films: A promising candidate for self-cleaning smart window applications

Thin Solid Films

Optical and structural properties of sol–gel prepared MgZnO alloy thin films

Journal of Materials Science: Materials in Electronics

Optical studies on Mg x Zn1−x O wide band gap semiconductor in the perspective of phase equilibrium

Journal of Applied Physics

Composition dependent ultraviolet photoresponse in MgxZn1−xO thin films

Applied Physics A

Optical and structural properties of MgZnO/ZnO hetero- and double heterostructures grown by pulsed laser deposition

Optical and Quantum Electronics

Crystal orientation effects on electronic and optical properties of wurtzite ZnO/MgZnO quantum well lasers

Effect of post-annealing on the band gap of sol-gel prepared nano-crystalline MgxZn1-x O (0.0 ≤ x ≤ 0.3) thin films

Journal	Journal of Sol-Gel Science and Technology
ISSN	09280707
Open Access	No