Implication of Mn concentration on the properties of cerium oxide thin films

Suresh R,Indira Priyadharshini T,Thirumal Valavan K,Justin Paul M

doi:10.34256/nnxt2011

Abstract

Uniform and adhesive Manganese doped cerium oxide (MDC) films are successfully deposited by Nebulizer Spray Pyrolysis (NSP) technique. The MDC films are characterized by XRD, FT-IR, UV-ViS, PL and I-V analysis. X-ray diffraction peaks reveal the single-phase polycrystalline cubic fluorite structure with preferential orientation along (2 0 0) direction. The broad bands observed at 695, 659, 538 and 517 cm-1 are due to the envelope of (Ce=O) symmetric, asymmetric terminal stretching and phonon band of metal oxide (Ce-O) network from FT-IR spectra. The transmittance decreases with Mn concentration due to the increase in scattering of photon by crystal defects created by doping and lower ionic size of Mn. The electrons in the outer orbits have travelled to the higher energy levels and have occupied vacant positions in energy bands. Some of the NBE emission and green emission peaks are vanished at higher doping level of Mn. The occurrence of a strong and broad blue emission peak at 15% for MDC films has been confirmed from emission spectra.

Highlights

II-VI, IV-VI transition metal nanocrystalline thin films have attracted considerable interest of investigators because of their optical, electrical parameters in the optoelectronic, solar cells, IR detectors and photo induced devices [1,2,3,4,5]
Uniform and adhesive Manganese doped cerium oxide (MDC) films are successfully deposited by Nebulizer Spray Pyrolysis (NSP) technique
Mn doped CeO2(MDC) films deposited at an optimized substrate temperature 400oC with film thickness 451, 489, 534, 579and 608 nm are prepared through Nebulizer Spray Pyrolysis (NSP) technique

Summary

Introduction

II-VI, IV-VI transition metal nanocrystalline thin films have attracted considerable interest of investigators because of their optical, electrical parameters in the optoelectronic, solar cells, IR detectors and photo induced devices [1,2,3,4,5]. Manganese is considered to be one of the most useful VIIB group transition metal compounds, which has found applications in magnetic memory devices, ferrofluids, and other optoelectronic devices. Manganese oxide (MnO2) provides a lower cost and lower toxicity replacement for ruthenium oxide in supercapacitor applications [6]. An attempt has been made to prepare thin films of manganese doped ceria and investigate their structural, optical and electrical properties. The effect of manganese doping on the particle size, lattice parameter, electrical conductivity and band gap energy is investigated

Experimental details

Results and discussion

Electrical properties

Conclusion