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In this work, pure and Mn-doped nickel ferrite (Ni1-xMnxFe2O4, x = 0, 3, 6, 9, and 12 wt%) thin films were prepared using facile nebulizer spray pyrolysis technique. The effect of Mn concentration on the structural, optical, and magnetic properties was studied. The XRD pattern confirms the cubic spinel structure of Ni1-xMnxFe2O4 thin films and reveals the preferred orientation along the (311) direction for each film. Moreover, the average crystallite size (D) is found to increase from 13 to 30 nm with increasing Mn concentration. The FESEM micrographs exhibit randomly arranged plate-like and rice-like grains. The elements such as Mn, Ni, Fe, and O are confirmed by the EDX analysis. The optical band gap energy (Eg) varies between 2.90 and 3.60 eV. The Ni1-xMnxFe2O4 film prepared with 3 wt% of Mn exhibits superior ferrimagnetic behavior with the highest value of ηB (57.31) due to the high crystallinity, packing density, and smooth surface of the film. The present work shows that the facile nebulizer spray pyrolysis technique can produce high-quality Ni1-xMnxFe2O4 thin films with good magnetic properties. [ABSTRACT FROM AUTHOR]

We report a novel highly sensitive and pseudocapacitive transparent nickel oxide (NiO) thin film based electrode material fabricated on a conductive glass substrate using a facile binderless electrodeposition process. Effect of the incorporation of Mo-dopant ion on some surface structural and electrochemical properties of the electrode was examined for high performance optoelectronic and charge storage potentials. The material showed some uniqueness in some microstructural features and enhanced degree of crystallinity, suitable for charge extraction and transport with Mo doping. The deposited NiO film demonstrated red shift in band structure by exhibiting optical band gap narrowing from 3.88 to 3.61 eV with increasing Mo content. The degree of disorder as revealed from Urbach response of NiO film was found varying with Mo-content. The material also exhibited enhanced Ni2+ electronic transition states with increasing Mo content which quenched at a critical dopant concentration of 2.4 %. The fabricated NiO thin film electrode showed increased supercapacitive specific capacitance and areal capacity up to a peak value of 1412 Fg−1 and 101 mAh m−2 for 3 % Mo dopant content at 5 mVs−1 scan rate and 0.5 mA cm−2, respectively, but returned diminished at higher dopant content. Excellent cycling stability at ∼ 85 % after 5000 cycles, was also exhibited. Impedance spectroscopic features of Mo-doped NiO electrode indicated fast electrolytic ion transfer response with high rate charge storage capability. The study presents successful fabrication of Mo-modified NiO nanostructured electrode film and demonstrated the influence of Mo impurity on tailoring the properties of NiO host film as suitable electrode in high performance photocatalytic and supercapacitor devices. • Novel Pseudocapacitive Mo doped NiO Thin Film Electrode has been developed from simple two-electrode electrofabrication process • Microstructural studies revealed stoichiometric bunsenite NiO rock salt with fcc crystal structure. • Comparative electrochemical properties of NiO and Mo-doped Mo x O films as supercapacitive electrodes were examined. • The film demonstrated highly stable pseudocapacitive response with improved specific capacitance of 1412 Fg−1 and areal capacity of 101 mAh m−2 at 3% volume Mo dopant content. • The study showed that supercapacitive and photocatalytic properties of NiO thin electrode can be tailored by simply introducing Mo dopant impurity. [ABSTRACT FROM AUTHOR]