Electrical Characteristics and Nanocrystalline Formation of Sprayed Iridium Oxide Thin Films

Abstract

Nanostructure and electrical properties of iridium oxide () thin films prepared by spray pyrolysis technique (SPT) have been experimentally characterized. The effect of solution molarity (SM) and substrate temperature () on the nanostructure features and electrical conductivity of these films has been investigated. The results of X-ray diffraction (XRD) showed that all samples prepared at with different SM, appear almost in amorphous form. XRD revealed that the films deposited at were tetragonal structures with a preferential orientation along direction. Moreover, the degree of crystallinity was improved by solution molarity. Single order Voigt profile method has been used to determine the nanostructure parameters at different SM and . The dark conductivity measurements at room temperature as a function of SM were observed and the value of conductivity were slightly increases at higher SM, reaching the bulk value of 20 . The values of activation energy of and of were found to be 0.21 eV and ·, respectively.

Crystal imperfections and Mott parameters of sprayed nanostructure IrO2 thin films

“…Accordingly, the decrement of electrical resistivity was correlated with the film morphology changes of IrO 2 thin films. Similar results have been previously reported [19,26,27]. …”

“…The deposition of IrO 2 thin films can be prepared by using several techniques such as embrace thermal oxidation [20], anodic oxidation [21], reactive sputtering [22], electro deposition [23] and sol-gel processing [24] as well as, the chemical spray pyrolysis technique [25]. The last one is characterized as low-cost technique and has the ability to deposit large area, as well as it can be used to get thin films of ternary and quaternary alloys [26].…”

“…Furthermore, this method used to deposit many transition metal oxides, including iridium oxide [19,[25][26][27]. On the other hand, microstructure characteristics, crystal deformities, and imperfections as well as the associated physical features can be studied for nanosized materials by using several powerful techniques, e.g.…”

Activity and Stability of Electrochemically and Thermally Treated Iridium for the Oxygen Evolution Reaction

“…Literature data supports our assumption of higher resistivity in amorphous iridium oxide compared to crystalline IrO 2 . [51][52][53] With increase in annealing temperature from 300…”

Ultrafine Iridium Oxide Nanorods Synthesized by Molten Salt Method toward Electrocatalytic Oxygen and Hydrogen Evolution Reactions

“…21,22 Apart from the electrocatalysis, IrO2 nanostructures were also used in several other applications including sensing, 23 field emission, 24,25 Li-air battery, 26 electrical properties, etc. 27 IrO2 nanostructured materials were mostly synthesized by metal organic chemical vapor deposition (MOCVD) method. 23,28,29,30,31,32,33,34,25 A variety of IrO2 nanostructures have also been produced by various other techniques, including vapor phase transport process, 35 electrochemical synthesis, 13 arc vaporization, 36 hydrothermal, 4 reactive radio frequency magnetron sputtering (RFMS), 37 sol-gel, 38,39 wetness method, 9 Adams fusion method, 15,16 sulfite complex route, 14 thermal decomposition of precursor (H2IrCl6), 17 oleylamine-mediated synthesis, etc.…”