Characterization of Mn1.56Co0.96Ni0.48O4 films for infrared detection

Abstract

Mn 1.56 Co 0.96 Ni 0.48 O 4 films with spinel structure were prepared on Al2O3 substrate by chemical solution deposition method. The microstructure of the films was studied by atomic force microscope and field-emission scanning electron microscope. The current-voltage characteristics showed Ohmic conductivity in the temperature range of 245–295K. The conduction was described by a variable range hopping model for a parabolic density of states. The advantages of high characteristic temperature, as well as high transition temperature (201K) between ferromagnetic and paramagnetic phases make the Mn1.56Co0.96Ni0.48O4 films very promising for infrared detection, especially for functional devices by integrating magnetic and electronic properties of the materials.

In-plane impedance spectroscopy in aerosol deposited NiMn2O4 negative temperature coefficient thermistor films

“…A temperature dependent activation energy for electron hopping was found many decades ago, 1 but only more recently has a theoretically justified small polaron variable-range hopping (VRH) model been employed more frequently. [32][33][34][35][36] In this work, we present a detailed in-plane impedance spectroscopy (IS) study on approximately 2 lm thick NMO films produced via the aerosol deposition (AD) technique using glass and Al 2 O 3 substrates. 28 The recently developed AD technique offers several distinct advantages: it allows highly dense polycrystalline films of sub-micrometer grain size to be produced with a high deposition rate and without an additional sintering densification process.…”

Structural and electrical properties of Mn1.56Co0.96Ni0.48O4 NTC thermistor films

“…It can be seen that a linear relation exists between these two parameters for three samples, which is appropriate for VRH with a parabolic shape of DOS around the Fermi level [15]. In this model, it is assumed that the hopping between Mn 3+ and Mn 4+ can be regarded as the conduction between localized electron states of varying energy and spatial separation [11]. To derive the activation energy of the MCN films, the ln( /T) versus 1/T plot are presented in Fig.…”

“…5b. The characteristic temperature T 0 can be obtained from the slope of the straight line of ln( /T) versus 1/T plot and E can be calculated by the following equation [11]:…”

“…However, the materials fabricated in film form would be much better than that in bulk form for its development in modern electronic devices. Recently, our group have prepared high quality Mn x Co y Ni 3−x−y O 4 films by chemical solution deposition (CSD) method at a low crystallization temperature of 873 K [11,12]. * Corresponding author.…”

Structural and electrical properties of NixMn3−xO4 system ceramics for infrared sensors

“…Ni x Mn 3 − x O 4 crystallizes in air to form a cubic spinel phase in the temperature range of 730-875°C [2,3]. The composition and phase purity of nickel manganite can be maintained by quench cooling from 800°C to room temperature [4]. Electrical conduction is based on a hopping mechanism where electron transfer takes place between manganese atoms of different valences on neighboring lattice sites.…”