Abstract:DSA (dimensionally stable anodes)-type electrodes (TiO 2-RuO 2-WO 3 /Ti) were prepared by the thermal decomposition of proper metal precursor on titanium substrate. Electrochemical and corrosion characteristics of these electrodes were determined in [Fe(CN) 6 ] 3− /[Fe(CN) 6 ] 4− system and Na 2 SO 4 solution with the application of cyclic voltammetry and chronoamperometry. The electrode active surface area and the activity towards oxygen evolution were evaluated. Moreover, corrosion resistance of the tested e… Show more
“…On the other hand, the CoO x deposit shows the existence of a localized fissured morphology. Such morphologies are quite common in electrocatalytic electrodes based on 3d -metal oxides (Elezović 2021 ; Kim 2019 ; Kusmierek 2019 ). Fig.…”
In this study, we report elaboration of a thin film of CoO
x
on a low carbon unalloyed steel substrate by electrochemical route and the study of its electrocatalytic performances with respect to the evolution reaction of oxygen (OER) in NaOH medium. The elaborated deposits were well-characterized using X-ray diffraction. Kinetic and thermodynamic parameters such as exchange current density, Tafel slope, reaction order with respect to OH– ions and apparent activation energy were studied. The CoO
x
displays satisfactory OER performance in an alkaline medium, with a low overvoltage of 362 mV at 10 mA/cm
2
and a Tafel slope of 81 mV/dec at 293 K. The apparent kinetic activation energy (= 29.79 kJ/mol) was similar to those obtained for the reported catalytic electrode materials. The O
2
gas obtained on the cobalt oxide electrode was 2.865 mmol/s.cm
2
, which is 28 times higher than that obtained for the platinum electrode (0.102 mmol/s.cm
2
). Chronoamperometry demonstrates a better electrochemical stability under a polarization potential of 2 V in 1 M NaOH for nearly 25 h. The low cost, the high OER performance, as well as the good stability of the CoOx electrode make it a promising candidate for the industrial-scale water electrolysis.
“…On the other hand, the CoO x deposit shows the existence of a localized fissured morphology. Such morphologies are quite common in electrocatalytic electrodes based on 3d -metal oxides (Elezović 2021 ; Kim 2019 ; Kusmierek 2019 ). Fig.…”
In this study, we report elaboration of a thin film of CoO
x
on a low carbon unalloyed steel substrate by electrochemical route and the study of its electrocatalytic performances with respect to the evolution reaction of oxygen (OER) in NaOH medium. The elaborated deposits were well-characterized using X-ray diffraction. Kinetic and thermodynamic parameters such as exchange current density, Tafel slope, reaction order with respect to OH– ions and apparent activation energy were studied. The CoO
x
displays satisfactory OER performance in an alkaline medium, with a low overvoltage of 362 mV at 10 mA/cm
2
and a Tafel slope of 81 mV/dec at 293 K. The apparent kinetic activation energy (= 29.79 kJ/mol) was similar to those obtained for the reported catalytic electrode materials. The O
2
gas obtained on the cobalt oxide electrode was 2.865 mmol/s.cm
2
, which is 28 times higher than that obtained for the platinum electrode (0.102 mmol/s.cm
2
). Chronoamperometry demonstrates a better electrochemical stability under a polarization potential of 2 V in 1 M NaOH for nearly 25 h. The low cost, the high OER performance, as well as the good stability of the CoOx electrode make it a promising candidate for the industrial-scale water electrolysis.
“…An example of a chronoamperogram is presented in Figure 6 . The EASA values for the tested electrodes were calculated from the Cottrell equation [ 52 ]: where I is the current intensity, and other parameters have their usual meanings. The results of the calculations are presented together with the roughness factor values in Table 5 .…”
The commercial graphite felt GFA 10 was subjected to an activation process with the use of CO2 at 900 °C for 35 and 70 min. Pristine and heat-treated materials were characterized using various methods: low-temperature N2 adsorption, SEM, and EDS. Voltammetric measurements of GFA samples (before and after activation) as the working electrode were carried out. Voltammograms were recorded in aqueous solutions of 4-chlorophenol and sodium sulfate as supporting electrolyte. The catalytic activity of GFA samples in the process of 4-chlorophenol oxidation with the use of H2O2 was also investigated. The influence of graphite felt thermal activation in the CO2 atmosphere on its electrochemical and catalytic behavior was analyzed and discussed. Results of the investigation indicate that GFA activated in CO2 can be applied as an electrode material or catalytic material in the removal of organic compounds from industrial wastewater. However, the corrosion resistance of GFA, which is decreasing during the activation, needs to be refined.
“…Electrochemical advanced oxidation processes (EAOPs) have become one of the most important technologies for environmental remediation [6,7]; they can be used to oxidize nearly all types of organic compounds into harmless products via highly reactive hydroxyl radical (OH • ) having a redox potential of 2.8 V [8][9][10][11][12][13] The advantage of EAOPs is that they are "environment-friendly" as they do not transfer pollutants from a phase to another (as in adsorption) and they do not produce large amounts of hazardous sludge [14][15][16][17]. In EAOPs, the organic pollutants are destroyed by hydroxyl radical OH • which is generated through the electron donors, namely the adsorbed water/OH − groups, or by the superoxide radical ion (O 2…”
Barium hydrogen phosphate (BaHPO 4 ) thin films were electrodeposited on fluorine-doped tin oxide (FTO) and used as electrocatalysts for organics degradation. The effects of applied current density and deposition time on the phase and morphology of electrodeposited films were analyzed with X-ray diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, electrochemical impedance spectroscopy (Mott-Schottky) plots, and photocurrent response. The electrodeposited BaHPO 4 films crystallize in the orthorhombic structure and form platelets on the FTO substrate. Response surface methodology (RSM) was used to optimize the operational conditions. Four independent process variables were considered: NaCl concentration, rhodamine B (RhB) initial concentration, applied current density, and reaction time. Based on the model prediction, the optimum conditions for RhB degradation were determined with the maximum RhB degradation of 98.78%. The corresponding experimental value of RhB degradation under the optimum conditions was determined as 99%, which is very close to the optimized one, implying that RSM is a powerful strategy for the process optimization. The photoelectrochemical degradation of RhB, performed at optimal operational conditions, allowed the very fast degradation rates of almost 99% during 7 min due to the synergic effect while combining photocatalysis and electrocatalysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
