Heat-treated Films Research Articles

Structural and optical study of spin-coated camphorsulfonic acid-doped polyaniline/titanium-di-oxide nanoparticles hybrid thin films

Polyaniline (PANI) doped with Camphorsulfonic acid (CSA) has been prepared by chemical oxidative polymerization and blend with titanium-di-oxide (TiO2) nanoparticles prepared by sol–gel method to form CSA-doped PANI/TiO2 hybrid thin films. The properties of as-deposited and heat-treated (100°C) hybrid thin films having different PANI:TiO2 weight ratios (1:0.5, 1:1, and 1:2) have been compared. FTIR study indicated that chemical bonding between CSA-doped PANI and TiO2 has been formed. XRD studies reveal that the as-deposited hybrid thin films are of amorphous nature and heat-treatment of such films initiates crystallization. SEM study shows that as-deposited hybrid films are rough; increase in TiO2 ratio and heat-treatment increased the roughness due to coalescing and agglomeration. UV–visible absorbance of hybrid films shows its characteristic peak in the visible region along with a peak in UV range and its intensity increased with TiO2 ratio and heat-treatment due to agglomeration of TiO2 particles. Photoluminescence spectra revealed that emission occurs in visible region (495nm) for as-deposited hybrid thin film and this emission increased with TiO2 ratio and heat-treatment of hybrid films.

Microstructures, mechanical properties and oxidation behavior of vacuum annealed TiZrN thin films

The purpose of this study was to investigate the effects of vacuum heat treatments on microstructures, associated mechanical behavior and oxidation behavior of TiZrN films. The films with three Zr/(Zr + Ti) ratios of 0.3, 0.5 and 0.7 were prepared using a DC reactive unbalanced magnetron sputter system. The annealing temperatures ranged from 700 to 1000 °C. X-ray diffraction (XRD) and microstructural examination revealed that both the as-deposited and heat-treated films exhibited a single TiZrN phase with columnar grains at the annealing temperature below 900 °C. At 1000 °C, ZrO2 phase appeared. In a temperature range from 700 to 900 °C in vacuum for 3 h, the heat-treated films showed a 15% drop in hardness, as compared with the as-deposited films. The slight decrease in hardness suggested that the heat-treated TiZrN films with a hardness level of application interest could be attributed to solid solution strengthening. Stress state of the films was found to be compressive. Substantial decrease in the magnitude of the residual compressive stresses could be achieved via heat treatment. At 1000 °C, the volume expansion arising from the oxidation of zirconium within the film may lead to an increase in residual compressive stresses of the films. The Ti0.7Zr0.3N film exhibited a lowest oxidation rate in the TiZrN coatings at 1000 °C in vacuum.

Carbon nanotube film anodes for flexible lithium ion batteries

In this study, carbon nanotube (CNT) film anodes are prepared for use in flexible lithium ion batteries, and the electrochemical performance of the CNT film anodes is evaluated. The CNT films are synthesized via chemical vapor deposition and direct spinning. The films are heat-treated under a nitrogen atmosphere at a high temperature to study the effects of heat treatment on the battery performance. The electrodes made with the CNT films are characterized via charge–discharge test, cyclic voltammetry, and impedance measurement. The results indicate that batteries with films heat-treated under a nitrogen atmosphere show a higher capacity, which can be a result of their high crystalline perfection. The impedance analysis shows that a lower resistance at the interface can be obtained by using heat-treated films. The charge–discharge tests are carried out by adjusting the rate from C/2 to 10C, and when the rate slows from 10C to 1C, the capacity of the samples largely recovers. The nitrogen/heat-treated CNT film electrodes present a capacity that is twice as high, such as 2C, 5C, and 10C, than untreated CNT film electrodes. These results indicate that the carbon nanotube film anodes have high potential for use in portable and wearable computers due to their flexibility.

Corrosion of Heat Treated Electroless-Ni Plated Mild Carbon Steels in Dilute H<sub>2</sub>SO<sub>4</sub>

The corrosion of heat-treated Electroless-Nickel (EN) plated mild carbon steel (MCS) in dilute H2SO4 is investigated and reported in the study. The MCS samples were electroless-Ni plated in alkaline Nimudeen 850. EN plated samples were soaked at different selected temperatures between 150-370 °C at constant time. The weight loss of the specimens by full immersion method was employed to assess the corrosion damage and corrosion rates of the as-received, EN plated MCS and four heat treated EN plated samples in the 0.5 M H2SO4 solution. The test specimens were regularly examined at every 12 hrs interval for 30 days (720 hrs). The materials corrodes in 0.5 M H2SO4 in the order of MCS10 > MCS14 > MCS15 > MCS11 > MCS13 > MCS12. Based on the results obtained, it will be justified to choose EN-plated samples (MCS 11) and the heat treated EN film (MCS12 and MCS13) for the purposed of solving the problem of corrosion in the medium. This is because; the application of EN deposition reduced the corrosion of MCS at much lower rate than the heat-treated EN film (MCS14 and MCS15) in 0.5 M H2SO4 environment. Atomic Absorption Spectrometer (AAS) Thermo series 2000 model and Scanning Electron Microscopy (SEM) with the Energy Dispersive X-Ray (EDX) facilities (Jeol JSM-7600F model) were used to ascertain the chemical compositions and the microstructures of samples.

Effects of heat treatment on morphology and crystallization of glass and film containing a large amount of CdO

The authors report the effects of heat treatment on the morphological and crystallization behaviors of photoresponsive 65CdO-17.5B2O3-17.5SiO2 (mol. %) bulk glass and its film. The bulk glass exhibited clear phaseseparation morphology when heat treated at 575°C for 1 h, and started to crystallize preferentially into phases with high CdO contents after heat treatment at 595°C. Heat treatment of the films at 575°C for 2 h resulted in simultaneous phase separation and crystallization. The morphology of the film heat treated at 575°C was found to comprise discontinuous CdO-poor phases formed in the matrix of a CdO-rich phase; however, these discontinuous phases became interconnected upon subsequent heat treatment at temperatures over 575°C. Various phases were formed concurrently by crystallization, with relatively large crystals of high CdO content preferentially forming in the CdO-rich phase, whereas small crystals of low CdO content formed in the CdO-poor phase. It was found that the main crystals of the heat-treated films transformed into crystal phases with higher CdO contents with increasing heat-treatment temperature, and this is likely caused by the change in composition related to phase separation. Open image in new window

Effect of Heat Treatment on Human Hair Keratin Film

Human hair keratin film consisting of fine fibrous and particle structures has been utilized as an alternative device to hair samples. Since application of heat is a well-known factor causing hair damage, the thermal effects on the keratin films and hair samples were examined focusing on color change, morphological observation, protein solubility, and oxidative proteins. The opaque white appearance of the keratin film changed to a yellow/light brown color by the thermal treatments at more than 170°C. This color change at 170°C and higher was also detected by spectrophotometry. Scanning electron microscopy (SEM) observation showed that there was little change in the fine structures of the keratin films and hair samples even after a thermal treatment at 200°C for 10 min. When protein solubility of heat-treated keratin films and hair samples were examined using a solution containing dithiothreitol (DTT) and urea, the amounts of proteins solubilized from heat-treated keratin films and hair samples were less than those from untreated keratin film and hair samples. The protein solubility decreased in a heating timeand temperature-dependent manner. A linear relationship between solubilized proteins and a heating temperature of 110 to 160°C was found. Compared to hair samples, the degree of change was clearly evident in the keratin films. The solubilized proteins consisted of keratin and keratin-associated proteins (KAPs). The amount of carbonylated proteins increased in the films treated at 120–180°C. This data suggests that thermal treatment promotes protein oxidization and induce the formation of “Stable Structure” which has not yet been identified. In any event, hair thermal damage will be quantitatively evaluated using the keratin films in place of hair samples.

Highly conductive Cu2-xS nanoparticle films through room-temperature processing and an order of magnitude enhancement of conductivity via electrophoretic deposition.

A facile room-temperature method for assembling colloidal copper sulfide (Cu2-xS) nanoparticles into highly electrically conducting films is presented. Ammonium sulfide is utilized for connecting the nanoparticles via ligand removal, which transforms the as-deposited insulating films into highly conducting films. Electronic properties of the treated films are characterized with a combination of Hall effect measurements, field-effect transistor measurements, temperature-dependent conductivity measurements, and capacitance-voltage measurements, revealing their highly doped p-type semiconducting nature. The spin-cast nanoparticle films have carrier concentration of ∼ 10(19) cm(-3), Hall mobilities of ∼ 3 to 4 cm(2) V(-1) s(-1), and electrical conductivities of ∼ 5 to 6 S · cm(-1). Our films have hole mobilities that are 1-4 orders of magnitude higher than hole mobilities previously reported for heat-treated nanoparticle films of HgTe, InSb, PbS, PbTe, and PbSe. We show that electrophoretic deposition (EPD) as a method for nanoparticle film assembly leads to an order of magnitude enhancement in film conductivity (∼ 75 S · cm(-1)) over conventional spin-casting, creating copper sulfide nanoparticle films with conductivities comparable to bulk films formed through physical deposition methods. The X-ray diffraction patterns of the Cu2-xS films, with and without ligand removal, match the Djurleite phase (Cu(1.94)S) of copper sulfide and show that the nanoparticles maintain finite size after the ammonium sulfide processing. The high conductivities reported are attributed to better interparticle coupling through the ammonium sulfide treatment. This approach presents a scalable room-temperature route for fabricating highly conducting nanoparticle assemblies for large-area electronic and optoelectronic applications.

Effects of heat treatment on the morphological and crystallization behaviors of cadmium-silicate glasses and films

The authors report the effects of heat treatment on the morphological and the crystallization behaviors of a photoresponsive 65CdO-17.5B2O3-17.5SiO2 (mol%) bulk glass and its film. The bulk glass exhibited a clear phase-separation morphology when heat treated at 575 °C for 1 h, and started to crystallize preferentially into phases with high CdO contents after heat treatment at 595 °C. Heat treatment of the films at 575 °C for 2 h resulted in simultaneous phase separation and crystallization. The morphology of the film heat treated at 575 °C was found to comprise discontinuous CdO-poor phases formed in the matrix of a CdO-rich phase; however, these discontinuous phases became interconnected upon subsequent heat treatment at temperatures over 575 °C. Various phases were formed concurrently by crystallization, with relatively large crystals of high CdO content preferentially formed in the CdO-rich phase whereas small crystals of low CdO content formed in the CdO-poor phase. The main crystals of the heat-treated films were found to be transformed into crystal phases with higher CdO contents with increasing heat-treatment temperature, and this is likely caused by a change in the composition related to phase separation.

Influence of Heat Treatment on Charge/Discharge Characteristics of Sn-Ag Alloy Plating Films for Li-Ion Battery Anode

Introduction Lithium ion batteries have energy densities higher than those of conventional rechargeable batteries. Although graphite is currently used as the anode active material in lithium ion batteries, it is necessary to consider alternative materials for obtaining higher capacity. In this research, tin (991 mAh g-1) with a capacity higher than graphite (372 mAh g-1) was used as an active material. However, during charging and discharging of tin, it pulverizes due to a large volume change, and the cycling characteristics are deteriorated. Therefore, alloys such as Sn-Cu and Sn-Ni have been examined for suppressing volume change. The Sn-Ag alloy1) especially has been reported as an anode material with excellent cycling characteristics. The charge/discharge characteristic of an Sn-Ag alloy plating film produced by electrodeposition were reported.2) SANYO has reported3) that the cycling characteristics of tin were improved by heat treatment.In this study, we explored the influence of heat treatment of the Sn-Ag alloy plating film on copper on the charge/discharge characteristics. Experimental An Sn-Ag alloy plating bath4) containing 1 M K4P2O7+0.25 M Sn2P2O7+2 M KI+0.02 M AgI was prepared. Electroplating was carried out by the current regulating method at 25°C. A pure copper plate and a platinum plate were used as the cathode and anode, respectively. The current density was changed and Sn-Ag alloy plating films with various compositions were produced and subjected to stress relief heat treatment.The microstructure of the Sn-Ag alloy plating films was examined by field-emission scanning electron microscopy (SEM). The phase structure of the deposits was analyzed by X-ray diffraction (XRD).Electrochemical studies of the Sn-Ag alloy plating films were carried out with coin cells that were assembled in an Ar-filled glove box. Each coin cell consisted of a lithium foil as a counter electrode and the Sn-Ag alloy plating film as a working electrode. The electrolyte was 1 M LiPF6 in ethylene carbonate (EC) and diethyl carbonate (DEC) (1:1 vol%). Cycling tests were performed in the range 0.02-1.5 V (vs. Li/Li+) at a constant temperature of 25°C. Results and Discussion By changing the current density, a silver content in the range 5-60 at% in the Sn-Ag alloy plating films was obtained. The films were found to consist of a beta-Sn phase and an Ag3Sn phase by XRD. From the Sn-Ag alloy phase diagram, it was confirmed that the obtained Sn-Ag alloy plating films were an equilibrium phase. Moreover, when the silver content in the plating film was increased, there was a tendency for the roughness of the film surface to increase.Figure 1 shows the cycling characteristics of the Sn-10 at% Ag alloy plating film before and after heat treatment. In the first cycle, the discharge capacities of both films are almost the same (about 600 mAh g-1). After 3 cycles, the discharge capacity of the film before heat treatment decreased abruptly at the initial stage and remained at about 100 mAh g-1. In contrast, the heat-treated films showed a small deterioration in capacity at the initial stage and subsequently maintained a relatively higher capacity of about 400 mAh g-1. References 1) Jingtian Yin, Masashi Wada, Seiji Yoshida, Kouji Ishihara, Shigeo Tanase and Tetsuo Sakai, Journal of The Electrochemical Society, 150(8), A1129-A1135 (2003).2) Koichi Nishimura and Susumu Arai, of 80th Electrochemical Society, p481 (2013)3) Noriyuki Tamura, Ryuji Ohshita, Masahisa Fujimoto, Shin Fujitani, Maruo Kamino and Ikuo Yonezu, Journal of Power Sources, 107, 48-55 (2002).4) Susumu Arai and Tohru Watanabe, Electrochemistry, 65(12), 1097-1101 (1997).

Optical properties on thermally evaporated and heat-treated disodium phthalocyanine derivative thin films

Thin films were grown on quartz substrates and crystalline silicon wafers using disodium phthalocyanine and the organic ligands 2,6-diaminoanthraquinone, 2,6-dihydroxianthraquinone and its potassium derivative salt. The surface morphology of these films was analysed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). IR spectroscopy was employed in order to investigate possible changes of the intra-molecular bonds between the powder compounds and thin films. The optical parameters have been investigated using spectrophotometric measurements of absorbance in the wavelength range of 200–1100 nm and the effects of post-deposition heat treatment were analysed. The absorption spectra recorded in the UV-Vis region for the deposited samples showed two bands, namely the Q and Soret bands. The absorption coefficient in the absorption region reveals non-direct transitions. In addition, the optical gap dependence upon the thickness of these thin films was evaluated.

Preparation and Effect of Heat Treatment Temperature on the Crystal Phase of Anodic Aluminum Oxide Films

The anodic aluminum oxide (AAO) films were prepared by anodization method from the 15 vol. % sulphuric acid solution, and prepared AAO films were heat-treated in the ranges of 25~1000°C. AAO films were characterized by EDAX, SEM and XRD techniques, respectively. The crystal phases of prepared AAO film is amorphous. The apertures of AAO film are in 25~30 nm. AAO films are amorphous when heat treatment temperatures of AAO films are below 800 °C. After the AAO film being heat-treated in the ranges of 850°C~900 °C, the heat-treated AAO film are γ-Al2O3film. When the AAO film is heat-treated at 950 °C, the part of γ-Al2O3change into α-Al2O3, and the heat-treated AAO film are mixed film of γ-Al2O3and α-Al2O3. After the AAO film being heat-treated at 1000 °C, the heat-treated AAO film is α-Al2O3film.

Characterization of Pb24Te76 quantum dot thin film synthesized by inert gas condensation

Air-stable and thermal-stable lead telluride quantum dot was successfully prepared on glass substrate by inert gas condensation (IGC) method. Argon (Ar) is the inert gas used during deposition process with a constant flow rate of 3×10−3Torr. The effect of heat-treatment process at different times was studies for structure, optical and electrical properties for nanocrystalline thin films. The structures of the as deposited and heat-treated films were investigated using grazing incident in-plane X-ray diffraction (GIIXD). The GIIXD pattern showed nanostructure face centered cubic structure of PbTe thin films. The energy dispersive X-ray analysis (EDX) of as deposited PbTe thin film was carried out and showed that the atomic ratio of Pb/Te was 24/76. The particle size of the as deposited PbTe film and after stored it in an unhumid atmosphere are 6.8±0.3nm and 7.2±0.3nm respectively as estimated form TEM image (i.e. in the same level of particle size). However, the particle size was changed to be 11.8±0.3nm after heat-treated for 5h at 473K. These particle size values of PbTe thin film are smaller than its Bohr radius. The estimated value of optical band gap Eg decreased from 1.71eV for the as deposited film to 1.62eV for film heat-treated (5h at 473K). The dc electrical conductivity is increased with raising temperature in the range (303–473K) for all thin films under investigation. The deduced activation energy decreased from 0.222eV for as deposited sample to 0.125eV after heat-treated at 473K for 5h.

Pd-Ni alloy nanoparticle doped mesoporous SiO₂ film: the sacrificial role of Ni to resist Pd-oxidation in the C-C coupling reaction.

A Pd-Ni alloy nanoparticle (NP) doped mesoporous SiO2 film was synthesized using a one pot inorganic-organic sol-gel process in the presence of structure director P123. Pure Pd and Ni NP containing films were also synthesized as controls. Overall a composition of 10 mol% metal (in the case of Pd-Ni, 5 mol% of each metal) and 90 equivalent mol% SiO2 was maintained in the heat-treated films. Grazing incidence X-ray diffraction and transmission electron microscopy studies of the final heat-treated Pd-Ni doped films revealed the (111) oriented growth of the Pd-Ni alloy NPs, with an average size of 5.3 nm, residing inside the mesopores of the SiO2 film. We performed the C-C coupling reaction employing the film-catalysts and the progress of the reaction was monitored using a fluorimeter. Overall, only the Pd-Ni alloy NP doped film showed good catalytic activity with excellent recyclability. It has been determined that the higher oxidising ability of metallic Ni restricted the oxidation of Pd in the Pd-Ni alloy catalyst under the reaction conditions, leading to the maintained reusability in consecutive cycles.

Fabrication method and characterization of electrodeposited and heat-treated iridium oxide films for pH sensing

A newly developed pH electrode that is formed on a glass substrate is demonstrated. Its fabrication involves the electrodeposition of iridium oxide (IrOx) onto a Au thin-film at a constant current of 0.01mA, followed by sequential electrode heat treatment at 400°C. The prepared electrode exhibited a near-Nernstian pH response of 59.5 (±1) mV/pH, comparable to the theoretical sensitivity (59mV/pH); this characteristic is highly desirable as it allows for the electrode predictable in measuring potentials when considering that IrOx electrodes prepared by a hydrated method are known to exhibit a super-Nernstian pH response (from 59 to 80mV/pH). Electrodeposition of IrOx produces a porous structure on the electrode surface, while IrOx film thickness is decreased by heat treatment; these processes may also affect the oxidation state of IrOx films. Cathodic charge storage capacities (CSCC) were measured by cyclic voltammetry as 72 and 48mC/cm2 for the non-heat-treated and heat-treated IrOx electrodes, respectively, corresponding to a CSCC value almost equivalent to the iridium amount, which is related to IrOx film thicknesses. Open-circuit potentials were measured to evaluate performances related to pH sensitivity, response time, and reversibility in the pH range of 2.38–11.61. Furthermore, individual electrodes prepared by the same fabrication process showed consistency in terms of sensitivity, with correlation coefficients over 0.999.

Thin Film Systems Based on Co and Cr Or Cu: Magnetoresistive Properties and Application

This article is presented the magnetoresistive properties and detailed examination of phase state and crystal structure on the as-deposited and heat-treated thin film systems Co/Cr/Co and Co/Cu/Co. In this systems observed two different types of structures (multilayer and granular film), which can be used as sensing elements of magnetic sensors.

Effect of heat-treatment on the structural and optical properties of Cu2S thin films deposited by CBD method

Semiconducting Cu2S thin films were successfully deposited on glass substrate under three different conditions such as as-deposited, post heat-treated and pre heated precursor solution by chemical bath deposition technique. Structural and optical properties of the films were characterized by X-ray diffraction (XRD), scanning electron microscope, energy dispersive X-ray (EDX) analysis and UV–Visible spectrophotometer. The XRD spectra showed the amorphous nature of thin films with hexagonal structure. The d value and micro strain increased and the average crystallite size decreased from 1.9 to 1.4 and 1.3 nm respectively when the as-deposited film was subjected to post heat-treatment and the precursor solution temperature was elevated. The presence of more nucleation centers and fast reaction rate decreased the average crystallite size in films grown with pre heated precursor solution. The noticed blue shift in energy gap and the shift of XRD peak position towards the lower 2θ side by heat-treatment could be considered as a sign of the quantum confined effect due to the formation of the nano-sized Cu2S crystals on the surface. The transmittance of heat-treated Cu2S films in the visible region matched the phototropic vision of human eye (~600 nm) which makes them suitable for solar control coatings on architectural windows and automobiles in the regions with warm climates. Low transmittance behaviour of pre heated Cu2S films could be used for anti dazzling coatings for car windscreens and driving mirrors to reduce the dazzling effects of light at night. EDX spectra showed the chemical purity of the films. The observed broad absorption and blue shift in band gap of the heat-treated films were due to quantum confinement effect. Fourier transform infrared studies were also carried out and the results are presented.

Heat-treatment to suppress the formation of Kirkendall voids in Sn-3.5Ag/Cu solder joints

Sn-3.5Ag solder reacted with heat-treated Cu films, and the characteristics of Kirkendall void formation at the Cu3Sn/Cu interface were investigated. Heat-treatment for the suppression of Kirkendall void formation in Sn-3.5Ag/Cu solder joints was conducted at varying temperature (T=400, 500 and 600°C). The results showed that S segregation on the void surfaces were effectively suppressed by heat-treatment, and Kirkendall voiding at the Cu3Sn/Cu interface decreased as the heat-treatment temperature was increased. According to the solid solubility limit of sulfur in Cu, S in Cu film was in solid solution at all heat-treatment temperatures, so the amount of sulfur segregation was reduced.

High-temperature thermal stability of nanocrystalline Cr2O3 films deposited on silicon wafers by arc ion plating

In this work, the high-temperature thermal stability of nanocrystalline Cr2O3 films on Si wafers deposited at various bias voltages was systematically investigated by means of a symmetrical high-resolution thermogravimetric system. In the meantime, the effects of substrate bias voltage on the morphology, microstructure, crack area percentage, phase constituents, and grain size of the heat-treated Cr2O3 films were also studied in detail. The results showed that the Cr2O3 films presented the higher thermal stability in pure nitrogen than in air up to 1200°C because the brittle oxidation product was more prone to cracking and chipping. As the bias voltage was −100V, the Cr2O3 film showed the highest thermal stability which was attributed to its most compact structure and the lowest defect density. After the heat treatments, all the films cracked due to the big difference in thermal expansion coefficient between the Cr2O3 film and Si wafer, which caused large thermal stresses. And some obvious micro-cavities were left in the film cross section after oxidation owing to the vaporization of Cr2O3 in oxygen containing atmosphere. In addition, the heat treatment also had a strong influence on the grain size of the Cr2O3 films.

Effect of aluminum chloride on formation of a polyconjugated bond system in the initial stage of polyvinyl alcohol thermal decomposition

Fine-structure bands have been located in electronic absorption spectra of polyvinyl alcohol (PVA) films decomposed thermally in air at 80–150°C. Doping of the PVA film with aluminum chloride (thermolysis catalyst) was found both to enhance the degree of thermal decomposition and to reduce the starting temperature for formation of poly-π-conjugated chains although it had no effect on the spectral positions of the polyene-unit absorption bands. Values of the band gap of heat-treated PVA films were determined to be in the range 1.65–1.78 eV based on an analysis of the electronic spectra long-wavelength edge.

Application of carbonated apatite coating on a Ti substrate by aqueous spray method

The fabrication and characterization of a carbonate-containing apatite film deposited on a Ti plate via an aqueous spray method is described. The mist of the spray solution emitted from a perpendicularly oriented airbrush was made to strike a warmed Ti substrate. The thicknesses of the sprayed film and those heat-treated at 400°C–700°C under Ar gas flow were in the range 1.21–1.40μm. The results of elemental analyses and Fourier transform infrared spectroscopy of the powders that were mechanically collected from the surface of the sprayed film suggest that the film was Ca10(PO4)6(CO3)·2CO2·3H2O. The presence of the carbonate ion and the lattice CO2 molecule was confirmed via the aforementioned analyses; the finding was also consistent with the X-ray diffraction patterns of the films and the chemical identity of the sprayed and heat-treated films that were measured using X-ray photoelectron spectroscopy. The sprayed film comprises a characteristic network structure, which contains round particles within the networks, as was observed by field-emission scanning electron microscopy. A scratch test indicated that the shear stress of the sprayed film (21MPa) significantly improved to 40 and >133MPa after heat-treatment at 600°C and 700°C, respectively, under Ar gas flow for 10min.