Effect of thermal annealing on the optoelectronic properties of Cu-Fe-O thin films deposited by reactive magnetron co-sputtering

Abstract

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Influence of substrate temperature on delafossite CuFeO2 films synthesized by reactive magnetron sputtering

“…Based on our previous assumption, on which oxygen content would be affected by the temperature deposition, a progressive decrease of the refractive index would then be expected with the deposition temperature elevation. In previous study dealing with the annealing conditions of sputtered CuFeO2 films [35], it was observed that a slight enhancement of the reductive conditions (increase of annealing temperature in primary vacuum) leads to the formation of Cu2O and Fe2O3 phases from rhombohedral delafossite phase, while with even more reductive conditions (same temperature range combined with secondary vacuum) only Cu and Fe3O4 phases crystallize. Refractive indices of Cu2O and Fe2O3 are 2.6 to 2.27 and 2.78 to 2.66 in the infrared range (1000 to 2600 nm, respectively) [36], and the refractive indices of metallic Cu included from 0.46 to 1.09 and of the spinel Fe3O4 are included from 2.13 to 2.85 at 1000 to 2600 nm, respectively.…”

The Impact of Temperature and Power Variation on the Optical, Wettability, and Anti-Icing Characteristics of AZO Coatings

“…Electron scattering impacts the transmission of light while operating at elevated powers and temperatures as a result of larger crystallite sizes and rougher surfaces. The film thickness was determined by using transmission data through the Swanepoel envelope technique [59]. It was noted that when the level of deposition power increased from 200 to 260 W, the film thickness also increased from 1079 to 1198 nm.…”

“…The value of refractive index 'n' for the sputtering power of 200 to 260 W is in the range of 1.49 to 1.51, while for deposition temperature from 50 to 200 °C, it varies from 1.50 to 1.52, which is mentioned in Table 3. The film thickness was determined by using transmission data through the Swanepoel envelope technique [59]. It was noted that when the level of deposition power increased from 200 to 260 W, the film thickness also increased from 1079 to 1198 nm.…”

“…Alqahtani The measurement of the optical band gap for the thin film was performed using the absorption spectra of films, where absorption spectra were determined as a function of wavelength. With the help of the Tauc relation [59], optical band gap of the film was found from the absorption coefficient α. Figure 5 shows the plot of (αhv) 2 on the vertical axis versus photon energy (hv) on the horizontal axis.…”

Enhanced Electrochemical Performance of MnCo1.5Fe0.5O4Spinel for Oxygen Evolution Reaction through Heat Treatment

“…Spinel oxides provide tunability of their properties through alterations to the synthesis conditions. − Magalhães et al studied the impact of heat treatment on the catalytic properties of iron cobaltite (FeCo 2 O 4 ) nanoparticles prepared via coprecipitation . The XPS results revealed a higher cobalt content on the surface of nonheated samples compared to those treated to 900 °C, which was attributed to the enhanced catalytic activity in the unannealed samples.…”