Dielectric and ferroelectric properties of CoCr₂O₄ nanoceramics

Abstract

CoCr2O4 nanoceramics are prepared by sol–gel auto combustion method. Synchrotron X-ray diffraction analysis affirms the single-phase pristine cubic structure with space group [Formula: see text]. Debye–Scherrer method estimates the crystallite size of main intense peak to be [Formula: see text][Formula: see text]nm. Prominent bands obtained in infrared spectra at 448 and 599[Formula: see text]cm[Formula: see text] are due to metal–oxygen stretching bond present at tetrahedral and octahedral sites. Dielectric parameters decrease as frequency increases from [Formula: see text] to [Formula: see text][Formula: see text]Hz that can be interpreted by Maxwell–Wagner-type interfacial polarization. Complex impedance spectra (Nyquist plot) reveal arc like behavior, which is mainly due to intergrain (grain boundary) resistance that also exhibits conducting nature of the nanoceramics. Weak ferroelectricity is mainly associated with the partial reversal of the polarization. Leakage current behavior follows the Ohmic and Child square law. Electron conduction process was interpreted by space-charge limited current (SCLC) mechanism. Leakage current behavior observed in cobalt chromite nanoceramics is mainly attributed to the oxygen vacancies.

Investigations of 2D Ti 3 C 2 ( MXene )‐ CoCr 2 O 4 nanocomposite as an efficient electrode material for electrochemical supercapacitors

“…Obtained pattern was in accordance with JCPDS card no. 780711 with lattice parameter a = 7.7 A°, respectively 44 …”

“…780711 with lattice parameter a = 7.7 A , respectively. 44 Figure 1B shows XRD pattern of MXene having hexagonal structure with characteristic peaks appeared at 2θ = 9.2 , 18.8 , 23.4 , 28.4 , 34.6 , 36 , 38.2 , 40.2 , 43.4 , 50 , 52.3 , and 60.5 corresponds to (002), (004), (006), ( 008), ( 101), ( 103), ( 104), ( 105), ( 002), ( 107), (108), and (110) planes, respectively, in accordance with JCPDS card no. 52-0875.…”

“…Novelty of present work is to understand MXene based spinel type cobalt chromite nanomaterial potential impact including structure, crystallinity, morphology, cation distribution and overall electrochemical performance as supercapacitor electrode using 0.1 M KOH and 1 M H 2 SO 4 electrolytes. 1 M H 2 SO 4 was selected because it shows largest capacity, substantive expansion, and shrinkage phenomenon among aqueous electrolytes 44 . Phase identification, morphological nature and elemental analysis were carried out using X‐ray diffraction, scanning electron microscopy and energy dispersive X‐ray spectroscopy.…”

“…1 M H 2 SO 4 was selected because it shows largest capacity, substantive expansion, and shrinkage phenomenon among aqueous electrolytes. 44 Phase identification, morphological nature and elemental analysis were carried out using X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. For electrochemical testing, sample were characterized via electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge discharge analysis.…”

Facile Synthesis of Spinel CoCr2O4 and Its Nanocomposite with ZrO2: Employing in Photo‐catalytic Decolorization of Fe (II)-(luminol-Tyrosine) Complex.

“…Kind-II multiferroic materials, such as pristine spinel CoCr2O4 nanoceramics, are a type of material that manifests magnetoelectric coupling as well as two or more ferroic features. Storing charges in electronic memory devices are made much more efficient using these nanoceramics [19]. The goal of this work project is to focus on the facile synthesis of spinel CoCr2O4 nanocrystals using coprecipitation and then modified with ZrO2 in 1:2 and 1:3 ratios using ultrasonic waves, to reduce the recombination and increase the surface acidity.…”