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The purpose of the article was to determine the influence of calcium carbonate and its modification (with stearic acid) on selected properties of composite polypropylene films and their processing. Polypropylene composites containing, respectively, 5, 10, 20 and 30 wt% filler, were made in twin-screw extrusion process with cold granulation. Films, on the other hand, were produced in single-screw extrusion process (an extruder with a screw with diameter d = 20 mm and ratio l/d = 24) using a flat head (so-called cast films) and a chill roll type cooling and pull-back device. The pull-back rotational speed was selected so as to obtain films of a thickness of approx. 120 µm, irrespectively of the composite being processed. The assessment of the effect of the addition of applied fillers on the magnitude of the melt volume-flow rate (MVR) of polypropylene and the processing characteristic of extrusion process was made (the flow resistance and the variations in volumetric flow rate were determined). It was demonstrated how variations in the processability of polymeric material determined the correction of extrusion process setup parameters (pull-back system speed). The processability of composite films under extensional flow conditions was also determined by evaluating the extensional viscosity (ηE) of the composites. The strength values of composite films were determined under static tension conditions and in puncture tests. The effect of the content and modification of CaCO3 on the film haze and gloss was also assessed. The investigation carried out has demonstrated a direct effect of the addition of calcium carbonate and its modification on the processability and selected functional properties of composite films. The study has also proved that stearic acid is an effective modifier of processing properties, not only in shear flow conditions, but also under extensional flow conditions – smaller ηE values are exhibited by films containing modified calcium carbonate.

The salt of formula [H2EDTA2+][HSO4−]2 (dihydrogen ethylenediaminetetraacetate di(hydrogen sulfate(VI)) was used to examine the physicochemical properties of the resulting Ni layer and evaluate the applicability of the salt as a new additive for Watts-type baths. The Ni coatings deposited from baths containing [H2EDTA2+][HSO4−]2 were compared with those obtained from other baths. The nucleation of nickel on the electrode was proven to occur the slowest in the bath that contained the mixture of [H2EDTA2+][HSO4−]2 and saccharin compared with other baths. The addition of [H2EDTA2+][HSO4−]2 alone (bath III) generated a coating with a morphology similar to that obtained from bath I (without additives). Despite the similar morphology and wettability of the Ni-coated surfaces plated from various baths (all Ni coatings were hydrophilic with contact angles in the range of 68 to 77°), some differences in electrochemical properties were noted. The corrosion resistance for the coatings plated from baths II and IV containing saccharin (Icorr = 1.1 and 1.5 µA/cm2, respectively) and the mixture of saccharin and [H2EDTA2+][HSO4−]2 (Icorr = 0.88 µA/cm2), respectively, was similar or even better than the coating obtained from baths without [H2EDTA2+][HSO4−]2 (Icorr = 9.02 µA/cm2).

This paper describes the use of a combination of two specific layers to protect the surface of low–carbon steel against electrochemical corrosion phenomena, which has not been published in the scientific literature so far. The layers include a black oxide film and siloxane coating, which are formed in the steel blackening and sol–gel processes, respectively. The so–obtained samples were subjected to surface morphology and physicochemical analysis (atomic force microscopy and Fourier-transform infrared spectroscopy) as well as electrochemical measurements, including AC and DC techniques. The physicochemical and surface morphology analysis allowed to prove the presence and adhesion of the siloxane coating to the surface of the black oxide layer, while the results of the electrochemical tests show that low–carbon steel modified this way is characterized by remarkable anti–corrosive properties, comparable to those of stainless steel.

A functional PbO-lignin electrode hydrid material composite was designed and manufactured. Moreover, its connection efficiency was confirmed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). We noted that the superficial layers of PbO combined with layers of the biopolymer and that oxygen atoms present in both materials had influence on the chemical environment of the neighboring compound. Hence, it can be said that the addition of PbO significantly contributes to the improvement of thermal stability of the final inorganic-organic system. In the framework of the study, the dispersive, morphological and structural characteristics were determined using scanning electron microscopy (SEM) and laser diffraction method. Electrochemical studies indicated that the PbO-lignin material exhibits better electrochemical properties compared to PbO without the addition of kraft lignin (increased capacitance, lower charge transfer resistance), as the specific capacitance after 5000 charge/discharge cycles was still at 95% of the initial value. Such promising operating parameters show that this material can be successfully used as an electrode material for energy management systems.

This study discusses the influence of different composition of negative electrode material on the performance of Ni-MH cells. Two major groups of multicomponent alloys were used during the experiments: AB5 and AB2 types. The best capacity was observed for the AB5-type alloy with the highest content of Co in its structure. The presence of Co in the alloy increased the capacity of the negative electrode most likely as a result of hydriding/dehydriding processes or Faradaic reaction following the dissolution-precipitation mechanism. The influence of different amounts of nickel (0–20 wt%) was determined. The presence of nickel in the electrode materials increased the current density as well as the diffusion of hydrogen into the bulk of alloys. Moreover, the carbon materials have been used as an additive for negative electrode grains in order to increase the conductivity and hydrogen sorption properties.

The overpotential of hydrogen evolution reaction is one of the aspects which results in low efficacy of water electrolysers. There is a constant search for new ways to improve the catalytic activity, especially of nickel-based materials. Addition of lanthanum results in synergism and high activity towards the hydrogen evolution reaction. Due to the application of deep eutectic solvents which are characterized by a wide electrochemical window and good solvent properties for metal ions, it was possible to deposit the lanthanum–nickel alloy coating which was composed of around 40% of La. Hydrogen evolution reaction conducted on this layer resulted in a reduction of overpotential by 129 mV in comparison to pure Ni layer at current density of 1 mA cm−2. Other kinetic parameters, such as Tafel slope and exchange current density, were also significantly improved.

Carbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small number of activated carbons obtained from coffee waste to improve the hydrogen electrosorption properties. The produced activated carbons differed in terms of their physicochemical properties due to the different coffee waste-to-KOH ratio (1 : 1–1 : 4). Pressure measurements confirmed their effectiveness in relation to unconsumed hydrogen release, which initially hindered fuel diffusion. Nevertheless, it has been established that the addition of activated carbons improved the electrocatalytic activity of the anode, especially during cyclic operation (coulombic efficiency increased from 23% to 44% of the theoretical value). Moreover, X-ray photoelectron spectroscopy revealed that borohydride as a known reducing agent caused the reduction of oxygen functional groups on the carbon surface during DBFC operation, which made it possible to eliminate one of the factors influencing the BOR characteristics, and thus a more precise comparison of the analyzed activated carbons.

Carbon felts are flexible and scalable, have high specific areas, and are highly conductive materials that fit the requirements for both anodes and cathodes in advanced electrocatalytic processes. Advanced oxidative modification processes (thermal, chemical, and plasma-chemical) were applied to carbon felt anodes to enhance their efficiency towards electro-oxidation. The modification of the porous anodes results in increased kinetics of acetaminophen degradation in aqueous environments. The utilised oxidation techniques deliver single-step, straightforward, eco-friendly, and stable physiochemical reformation of carbon felt surfaces. The modifications caused minor changes in both the specific surface area and total pore volume corresponding with the surface morphology. A pristine carbon felt electrode was capable of decomposing up to 70% of the acetaminophen in a 240 min electrolysis process, while the oxygen-plasma treated electrode achieved a removal yield of 99.9% estimated utilising HPLC-UV-Vis. Here, the electro-induced incineration kinetics of acetaminophen resulted in a rate constant of 1.54 h−1, with the second-best result of 0.59 h−1 after oxidation in 30% H2O2. The kinetics of acetaminophen removal was synergistically studied by spectroscopic and electrochemical techniques, revealing various reaction pathways attributed to the formation of intermediate compounds such as p-aminophenol and others. The enhancement of the electrochemical oxidation rates towards acetaminophen was attributed to the appearance of surface carbonyl species. Our results indicate that the best-performing plasma-chemical treated CFE follows a heterogeneous mechanism with only approx. 40% removal due to direct electro-oxidation. The degradation mechanism of acetaminophen at the treated carbon felt anodes was proposed based on the detected intermediate products. Estimation of the cost-effectiveness of removal processes, in terms of energy consumption, was also elaborated. Although the study was focussed on acetaminophen, the achieved results could be adapted to also process emerging, hazardous pollutant groups such as anti-inflammatory pharmaceuticals. Electrocatalytic performance of oxygen-activated carbon fibre felt anodes mediating degradation mechanism of acetaminophen in aqueous environments

Designing cost-effective oxygen evolution reaction (OER) electrocatalysts is essential for sustainable water splitting. Recently, amorphous transition metal borides (TMBs) as OER pre-catalysts have acquired growing attention due to their favorable characteristics such as high conductivity, compositional and structural flexibility. Nevertheless, rational design of boride-based OER pre-catalysts remains an ongoing challenge. Herein, an efficient pre-catalyst derived from FeB with accelerated surface reconstruction and regulated intrinsic activity of evolved FeOOH is obtained by W and P co-doping. The obtained catalyst demonstrates an excellent OER activity with a low overpotential of 209 mV at a current density of 10 mA cm−2, and good stability in alkaline electrolyte, which surpasses most of boride-based OER catalysts. Specifically, the anion etching facilitates the surface reconstruction and accelerates the mass/charge transfer. Density functional theory calculations suggest W doping can enhance intrinsic catalytic activity via optimizing the adsorption free energy of reaction intermediates and improving the conductivity. Additionally, the hierarchical structure and amorphous feature also benefit the OER process. This study provides a fundamental insight into the correlation between surface structure and catalytic activity, and a powerful strategy to construct efficient OER pre-catalysts.

Activated carbons have been obtained from the following organic precursors (lignocellulosic waste materials): willow, rapeseed straw, hemp shives, flax shives, switch grass, Virginia mallow and giant miscanthus. The activation process has been performed by using potassium hydroxide at 750 °C. Elemental analysis has been performed in order to determine the presence of heteroatoms in the carbon structure. Boehm titration was used to estimate the functional groups of carbon materials. The surface area was characterized using gas adsorption method. All the obtained samples have been used as electrodes for electrochemical capacitors operated in 1 M H2SO4. The electrochemical characterization was carried out using cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. All measurements proved that carbon materials obtained from different lignocellulosic wastes are suitable for energy storage applications. Moreover, the content of oxygen groups has great influence on the charge storage mechanism. Excessive oxygen content causes the disruption of surface conjugation of the carbon material.

The research and development of new carbon materials of electrochemical capacitors cause a huge interest in chemical power sources causes. The appropriate modification of carbon materials leads to an increase in supercapacitor capacitance. Therefore, activated carbon was modified by ozone treatment. The process of ozonation was carried out for 15, 30, 60, 120 and 240 min. Moreover, activated carbon was also modified by cobalt(II) hydroxide impregnation in order to construct asymmetric electrochemical capacitor. The performance of electrochemical capacitors has been examined by cyclic voltammetry and galvanostatic charge/discharge in 1 M H2SO4, 1 M Na2SO4 and 6 M KOH

A new class of ionogels with a thiol-ene matrix showing a phase-separated morphology was obtained from triallyl isocyanurate and trimethylolpropane tris(3-mercaptopropionate) via a photo-induced polymerization in ionic liquids (ILs). The compatibility between the polymer matrix and ILs decreased with the decrease of the Kamlet-Taft α parameter of the solvent; polymerization was faster in ILs with higher values of the Kamlet-Taft β parameter. The matrix had a “colloidal gel” structure built of interconnected microspheres forming a 3-dimensional network percolating throughout the IL. For the first time, spherical poly(thiol-ene) particles were obtained in ILs; the size of the particles depended on the monomer concentration and the IL ability to stabilize the colloidal microspheres through H bonding. The low solubility of ILs in the matrix along with sufficiently strong interactions matrix/IL resulted in the appearance of anti-plasticization effect. The obtained ionogels had high ionic conductivity (∼2.6 ÷ ∼ 7.0 mS cm−1 at 25 °C) and very high relative conductivity (higher than the highest possible values resulting from the IL content); this allows the majority of the IL conductivity in the ionogel to be retained.

The capacitance of electrochemical capacitors may be improved by providing additional charge originating from faradaic reactions. Faradaic reactions may originate from appropriate modification of the electrode or the electrolyte. The introduction of thiourea to the electrolyte is a novel approach. The tests in 1 mol dm−3 of Na2SO4 aqueous electrolyte (pH = 6.2) with thiourea addition showed a reversible redox process resulting in the increase of capacitance from 131 F g−1 for non-modified electrolyte to 229 F g−1 for those modified with thiourea. Keywords: Supercapacitor, Thiourea, Carbon electrodes, Faradaic reaction

Due to their highly tunable electrical and structural properties, carbon materials are widely used in fuel cells. This study reviews the latest modifications carried out in order to improve the electrochemical properties of carbon-based anodes in Direct Borohydride Fuel Cell (DBFC). However, in this type of fuel cell, various types of carbon (e.g. carbon black, activated carbons, carbon nanotubes, graphene and heteroatom-doped carbons and MOF-derived carbon materials) can provide not only catalyst support, but also hydrogen storage due to the extremely complex process of borohydride electrooxidation. Accurate control of porosity and carbon morphology is therefore necessary for high fuel cell efficiency. Finally, some prospects for the future development of carbon materials for DBFC design are presented. It should be emphasized, that the storage of hydrogen in solid form is a possible breakthrough for the future use of hydrogen as an ecological fuel, which is why scientific research in this topic is so important.

The desirable properties of ionic liquids (ILs) enable their use in various branches of chemistry, through a wide range of applications, e. g. as organic electrolytes. In the present study, an efficient two-step method was developed for the synthesis of long-chain ionic liquids with alkyl derivatives of DABCO as cations and bis(trifluoromethane)sulfonimide as anions. ILs obtained with high yields (≥91 %) were solids with melting points that increased with the rise in the number of carbon atoms of the alkyl substituent in the bicyclic cation. The structure of the compounds was confirmed by spectroscopic methods and elemental analysis. All compounds were soluble in the main solvents except water and hexane. The solubility in organic solvents such as acetonitrile allowed the use of synthesized ILs in electrochemical capacitors. Electrochemical tests revealed that the ILs enhanced the conductivity of organic electrolytes. This phenomenon improved the cyclability and reduced the internal resistance of the electrochemical capacitors.

The earlier obtained organosilicon derivatives of rapeseed oil were used for the production of coatings protecting steel surface against corrosion. Vegetable oils have been hitherto used for temporary protection of metals against corrosion, while thanks to the synthesis of appropriate organosilicon derivatives, it is now possible to create durable protective coatings. Due to the presence of alkoxysilyl groups and the use of the sol-gel process, the coatings obtained were bonded to the steel surface. The effectiveness of the coatings was checked by electrochemical methods and steel surface analysis.

Silica aerogel-based materials exhibit a great potential for application in many industrial applications due to their unique porous structure. In the framework of this study, carbon fiber and nickel coated carbon fiber&ndash, silica aerogel nanocomposites were proposed as effective electromagnetic shielding material. Herein, the initial oxidation of the surface of carbon fibers allowed the deposition of a durable Ni metallic nanolayer. The fibers prepared in this way were then introduced into a silica aerogel structure, which resulted in obtaining two nanocomposites that differed in terms of fiber volume content (10% and 15%). In addition, analogous systems containing fibers without a metallic nanolayer were studied. The conducted research indicated that carbon fibers with a Ni nanolayer present in the silica aerogel structure negatively affected the structural properties of the composite, but were characterized by two-times higher electrical conductivity of the composite. This was because the nickel nanolayer effectively blocked the binding of the fiber surface to the silica skeleton, which resulted in an increase of the density of the composite and a reduction in the specific surface area. The thermal stability of the material also deteriorated. Nevertheless, a very high electromagnetic radiation absorption capacity between 40 and 56 dB in the frequency range from 8 to 18 GHz was obtained.

This study discusses the effect of 3-(1,1,2,2,3,3,4,4-octafluoropentyloxy)propyltriethoxysilane (OFTES) based coatings on the anti-corrosive properties of 304 type stainless steel, which has not been described to date. The coatings were deposited from methanol using the anhydrous deposition method and influence of the sonication on this process has also been investigated. Anti-corrosive properties of modified and unmodified steel surfaces have been characterized by electrochemical and surface analysis methods. Since silicon is an element capable of forming bonds with both organic and inorganic substrates, these features allow to combine organofunctional silanes with metal as well as steel surfaces through metal O Si covalent bonds. A fluorinated alkyl chain, which is attached to the silicon atom, forms an effective barrier against an aggressive aqueous environment.

Composites containing biological materials with nanostructured architecture have become of great interest in modern materials science, yielding both interesting chemical properties and inspiration for biomimetic research. Herein, we describe the preparation of a novel 3D nanostructured MnO2-based composite developed using a carbonized proteinaceous spongin template by an extreme biomimetics approach. The thermal stability of the spongin-based scaffold facilitated the formation of both carbonized material (at 650 °C with exclusion of oxygen) and manganese oxide with a defined nanoscale structure under 150 °C. Remarkably, the unique network of spongin fibers was maintained after pyrolysis and hydrothermal processing, yielding a novel porous support. The MnO2-spongin composite shows a bimodal pore distribution, with macropores originating from the spongin network and mesopores from the nanostructured oxidic coating. Interestingly, the composites also showed improved electrochemical properties compared to those of MnO2. Voltammetry cycling demonstrated the good stability of the material over more than 3,000 charging/discharging cycles. Additionally, electrochemical impedance spectroscopy revealed lower charge transfer resistance in the prepared materials. We demonstrate the potential of extreme biomimetics for developing a new generation of nanostructured materials with 3D centimeter-scale architecture for the storage and conversion of energy generated from renewable natural sources.

Calendar and cycle ageing affects the performance of the lithium-ion batteries from the moment they are manufactured. An important process that occurs as a part of the ageing is corrosion of the current collectors, especially prominent in the case of the aluminium substrate for the positive electrode. Generally, aluminium resists corrosion due to the formation of a non-permeable film of native aluminium oxide. Nevertheless, at certain electrochemical conditions corrosion affects the interface of the current collector. As a consequence of corrosion, the cathode materials lose electrical and mechanical contact with the current collector, leading to capacity and power fading. Therefore, a deeper understanding of this process and effective corrosion inhibition are necessary to prevent the deterioration of the battery performance. This review provides an updated critical overview of the mechanisms of aluminium corrosion, methodologies for analysing this phenomenon, and approaches for its effective mitigation. As the influence of multiple factors on the corrosion process has a central impact, the review discusses how they specifically affect the undergoing processes. Therefore, appropriate examples of important factors like electrolyte composition, thermal conditions and electrochemical parameters are presented to explain the specific mechanism of aluminium corrosion. Since corrosion inhibition is an important technological issue with a tremendous economic impact the review summarises how to achieve this by adjusting the electrochemical system and enhancing the knowledge on the safe operation of the positive electrode.

The influence of selected types of ammonium ionic liquid (AIL) additives on corrosion and functional parameters of lead-acid battery positive electrode was examined. AILs with a bisulfate anion used in the experiments were classified as protic, aprotic, monomeric, and polymeric, based on the structure of their cation. Working electrodes consisted of a lead-calcium-tin alloy utilized in the industry for manufacturing current collectors of positive electrodes in lead-acid batteries (LABs). This alloy was used in the first part of the study for the evaluation of corrosion intensity and stability of electrolyte with AIL additives. In the second part, the grid made of the examined alloy was covered with positive active mass, the composition of which was modified by selected AIL. The selection of an appropriate substance was made based on parameters such as corrosion potential, corrosion current, polarization resistance, and hydrogen and oxygen evolution potentials. Techniques such as linear sweep voltammetry, corrosimetry, and electrochemical impedance spectroscopy were used. The conducted measurements revealed that polymeric AIL additive had an exceptionally positive influence on the inhibition of the corrosion process in LAB and electrochemical window of the electrolyte. The influence of this compound on the specific capacity and resistance of the active mass was also discussed.

This paper discusses the effect of current collector (stainless steel 316L) corrosion on the performance of electrochemical capacitors operated in aqueous electrolytes. This topic seems to be often neglected in scientific research. The studied electrolytes were 1 M H 2 SO 4 , 1 M KI, 1 M Na 2 SO 4 , 1 M KOH and 6 M KOH. The corrosion process was investigated by means of selected direct and alternating current techniques. The surface of the current collectors as well as the corrosion products were characterised using scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy and atomic force microscopy. Stainless steel 316L in alkaline solutions is characterised by the lowest values of corrosion potentials whereas the potentials in acidic media become the most noble. Our studies show that corrosion potentials increase with decreasing pH value. This phenomenon can be explained with the formation of passive oxide films on the stainless steel current collectors. The passive oxide films are usually thicker and more porous in alkaline solutions than that in the other electrolytes. The processes occurring at the electrode/electrolyte interfaces strongly influence the working parameters of electrochemical capacitors such as voltage, working potentials of single electrodes, self-discharge as well as the internal resistance and cycling stability.

Heteroatom doping of carbon nanostructures is a convenient tool to control their physicochemical properties and to make them suitable for various applications. Carbon nano-onions (CNOs) doped with nitrogen (N-CNOs) have been prepared by annealing aminated-nanodiamond particles (AM-NDs) at different temperatures (1150, 1450 and 1650 °C) in an inert He atmosphere. Their physicochemical properties were compared with those of pristine CNOs obtained from non-functionalized NDs under the same experimental conditions. The carbon nanostructures were characterized using transmission (TEM) and scanning (SEM) electron microscopy, X-ray powder diffraction (XRD), Raman and Fourier transform infrared (FTIR) spectroscopy, porosimetry, and differential-thermogravimetric analyses (TGA-DTG). Their physicochemical properties are systematically discussed for undoped and for the nitrogen-doped CNO samples. The results reveal that the surface morphology and the structure of undoped and nitrogen-doped CNOs vary with the annealing temperature. All of these materials were electrochemically tested as electrode materials for enzyme-free catalysis of hydrogen peroxide. The nitrogen-doped carbon nanostructures have a higher catalytic activity than undoped nanostructures obtained under the same experimental conditions.

Praca powstala dzieki wsparciu finansowemu Polskiego Narodowego Centrum Nauki, w ramach grantu nr DEC-2013/09/N/ST5/00910 oraz projektu DS 3787/E-138/S/2017 finansowanego przez Ministerstwo Nauki i Szkolnictwa Wyzszego.

This paper presents a synthesis and characterizes highly amorphous lead dioxide and its use in hybrid electrochemical capacitor C/PbO2. Highly amorphous lead dioxide with a small amount of β-PbO2 was synthesized by galvanostatic deposition from acetate solution. The hybrid supercapacitor was constructed with PbO2 as the positive electrode whereas activated carbon as the negative electrode. The morphology of materials was examined by scanning electron microscopy and their structure was characterized by means of an X-ray diffraction technique. The electrochemical performance of hybrid electrochemical capacitor with synthesized PbO2 was studied by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. To indicate that the amorphous form of lead dioxide was predominant, results were compared to highly crystalline β-PbO2. The hybrid electrochemical capacitor with synthesized material exhibits a much greater specific capacitance, higher specific energy and power than the highly crystalline one. The specific capacitance values obtained for the supercapacitor rose more than twice in favour of amorphous PbO2. Also, long cycling did not influence any of the electrochemical properties of this hybrid electrochemical capacitor, which makes it an interesting energy storage device.

Aluminium anodisation processes were carried out in two different solutions i.e. in oxalic and sulphuric acid. Part of the samples was subjected to hydrothermal sealing in order to seal the pores on the oxide surface. Silane coatings were deposited from two solutions containing triethoxyoctylsilane and tetraethoxysilane. Surface analysis and spectroscopic methods were applied to characterize the pristine and coated samples. Anti-corrosive properties of all samples were assessed using electrochemical methods. It can be concluded that due to the condensation reaction between the anodised aluminium and silane compounds Al-O-Si covalent bonds are created. Fitted equivalent circuit parameters are distinctively different for the investigated systems. Additionally, the size of the particles in colloidal silane solutions was determined. Due to their size the colloidal particles cannot enter into the pores of the oxide layer but form a silane film on top. Thus they create a composite coating containing trapped air in the pores.

The activated carbon was modified by the wet method with a solution of ammonium persulfate at room temperature with different times. Kinetics studies showed that the modification took place mostly during the first 60 min of the process. The physicochemical properties of the obtained carbon were evaluated by thermogravimetric studies, Raman and FTIR spectroscopy, elementary and BET analyses. Furthermore, the fabricated material was applied in symmetric capacitors operated on the three aqueous electrolytes (1 M H2SO4, 6 M KOH and 1 M Na2SO4). Mild conditions of the modification process are optimal to obtain electroactive groups on the carbon surface, which make this material useful in a supercapacitor application. In our studies, we noticed that this type of functional groups mainly appears on the surface of the activated carbon, in the first oxidation stage. With prolonged oxidation, they may transform into undesirable groups. The results show that this kind of modification improves the capacity of all the tested supercapacitors. It was connected mainly with an increase of the carbon material’s wettability and in the case of capacitor operated in acid and base electrolytes due to a redox reaction of oxygen functional groups.