SS Electrodes Research Articles

Nitrate reduction on bimetallic (Pd0.09Sn0.91) electrodes: Effects of calcination temperature, electrode support, and quenching

The effects of fabrication process, namely, calcination temperature, electrode support, and quenching, on electrochemical nitrate reduction were investigated, exemplified by Pd0.09Sn0.91 electrode. The electrode was characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, and cyclic voltammetry. Results showed that electrode surface morphology, crystalline formation, and chemical composition, which were influenced by the electrode fabrication process, controlled nitrogen selectivity and nitrate reduction reactivity. The Pd0.09Sn0.91/SS electrodes were calcined at different temperatures (from 100 to 700 °C) for 3 h in air and the results showed that high calcination temperature rendered electrode oxidized, and decreased nitrogen selectivity and nitrate reduction capability. Electrode supports affected nitrate reduction following the order of Ni ≈SS > G > Ti. Quenching electrode in ice water decreased nitrate reduction capability. Porous surface with small oxygen content, less degree of metal oxidation (i.e., higher fraction of Pd0 and Sn0), and Sn crystals favored nitrogen selectivity and nitrate removal.

Heterostructured 3D-Co-MOF@CoO/Ni‖3D-C-Fe4N@NiCu/SS hybrids as high-performance electrode materials for efficient hybrid supercapacitor

Designing of 3D heterostructured hybrid materials are effective step, in the pursuit of attaining higher electrochemical performance compared to their pristine metal/metal oxide counterparts, owing to the enlarged active area of electrode-electrolyte interaction, and fast ion transportation path. In this regard, binder-free heterostructured electrodes, 3D-Co-MOF@CoO/Ni (positive) and 3D-C-Fe4N@NiCu/SS (negative) are fabricated to construct a hybrid supercapacitor (HSC). This core-shell structured positive electrode revealed better electrochemical performance (592.8 mC/cm2 at 2 mA/cm2) than bare CoO/Ni, which is nearly twice as good. Meanwhile, the hierarchical microporous 3D-C-Fe4N@NiCu/SS electrode achieved a broad potential of 0 to − 1 V with a maximum areal capacity of 852 mC/cm2 at 2 mA/cm2 and 72 % stability over 10000 GCD cycles. The 3D heterostructured morphologies of the electrodes endowed the 3D-Co-MOF@CoO/Ni‖3D-C-Fe4N@NiCu/SS HSC with a high volumetric energy value of 2.305 mWh/cm3 with a volumetric power of 325 mW/cm3. The unique architecture and engineering strategies adopted in this research work can pave the way to attain desired electrochemical output in the future.

Applicability of electrocoagulation process for removal of contaminants from debrominated wastewater

Debrominated wastewater (DWW) leftover, after the separation of bromine, from the effluent of various industries like fertilizer, pesticide, pharmaceutical, organic chemicals, etc. contains a large amount of COD, TDS, turbidity and color and cannot be discharged directly to water bodies. The investigation for DWW treatment by electrocoagulation (EC) was performed in a two-liter batch-type reactor using SS electrodes (Fe). With the four-plate configuration, a maximum COD, TDS, color, and turbidity removal of 45.5%, 26%, 86.5%, and 100% were obtained respectively, at their optimum pH 9, current intensity 2 amp, and electrode gap 1.5 cm. The maximum energy consumption of 4.2 Wh/L was observed at pH 5 while the maximum electrode loss (EL) was 1.995 g/L at pH 9. The best settling rate was found at pH 3, and the maximum weight of foam and residue of 7.31 kg/m3 was found at pH 9. Electrolysis time was also observed for all parameters.

High energy density supercapattery empowered by efficient binder-free three-dimensional carbon coated NiCo2O4/Ni battery and Fe3S4@NiCo pseudocapacitive electrodes

Through the progress of science and technology, the findings of supercharged electrodes are provoked to design the electrode material. Herein, a novel electrode made up of binary metallic oxide surrounded by a carbon matrix is designed as the positive electrode material that is substantially more active and efficient than the most reported electrode materials. The as-synthesized 3D-C-NiCo2O4 electrode revealed a specific capacity of 558.3C g−1 at 1 A g−1. Likewise, the 3D-Fe3S4@NiCo/SS electrode is effectively synthesized via the vapour phase growth method that worked as a negative pseudocapacitive material. It provides a gravimetric capacitance of 808.05 F g−1 at 1 A g−1. Moreover, the assembled 3D-C-NiCo2O4//3D-Fe3S4@NiCo/SS reveals a higher gravimetric capacitance of 150 F g−1 at 1 A g−1 with 70 % stability over 10,000 cycles. It offers a maximum energy and power density of 49.8 Wh kg−1 and 8100 W kg−1, respectively. These exceptional outcomes highlight that the as-fabricated 3D-C-NiCo2O4//3D-Fe3S4@NiCo/SS device can be an ultimatum source for high-performance energy findings. The present result demonstrates the combined approach of prepared electrodes, merits of battery type 3D-C-NiCo2O4 electrode, and the faradaic capacitance of 3D-Fe3S4@NiCo electrode.

Fabrication of a new rGO@PPy/SS composite electrode with high energy storage and long cycling life for potential applications in supercapacitors

Electrochemical synthesized PPy/SS and rGO@PPy/SS electrodes are individually characterized from the point of their morphological and structural properties by the SEM, EDX and FTIR techniques. Electrochemical measurements, for instance, CV, EIS, and MS are performed to obtain the supercapacitive behaviour of the electrodes in an aqueous solution of 0.1 M KOH. All the morphological and structural studies confirm the molecular occurrence of PPy and rGO@PPy, and the homogenous distribution of the material onto the SS substrate. The specific capacitances of the electrodes show up as 104.22 F g−1 and 122.53 F g−1 respectively for PPy/SS and rGO@PPy/SS at 10 mV s−1 scan rate. The energy density of rGO@PPy/SS is 212.5 Wh kg−1 at the current density of 6 A g−1 while the energy density of PPy/SS is 116.66 Wh kg−1 at the same scan rate. This considerable increase is also shown for the power densities of the electrodes as from 4516.12 W kg−1 to 6219.51 W kg−1 at 6 A g−1 by insertion of rGO into PPy/SS. Likewise, with this insertion, an impressive improvement in the cyclic stability of the electrode is seen from 59.5% to 97.6%. In the light of these results, rGO@PPy/SS is considered an extremely promising material for supercapacitor investigations.

Batch Electrochemical Treatment of Raw Pulp and Paper Mill Wastewater Using Electrode Combinations

SS and Cu electrodes were used in the electrochemical coagulation to treat pulp and paper mill wastewater using 4SS and 3SS 1Cu electrodes by applying cell voltages 12 – 24 V. Optimal cell voltage 18V showed COD removal of 89.64% for 4SS electrode and 84.74% for 3SS 1Cu electrode with simultaneous color removal of 99% and 90%. Other control factors used for optimal operation are sludge volume index (SVI), filterability, etc. SVI values were <100 mL/g for 4SS electrodes. The filtration characteristics of the ECC-treated sludge were established to determine the specific cake resistance (α) and the resistance of the filter medium (Rm). Lower α and Rm values for 4SS and 3SS-1Cu electrodes were found at 60 min ET. Proximate and ultimate analyses showed that 4SS and 3SS-1Cu sludge could be used as additive as well as adsorbent material for treating low strength wastewater.

Engineering of Thermally Converted 3D-NiO[sbnd]Co3O4/Ni//3D-ϒ-Fe4N[sbnd]C@Ni/SS Porous Electrodes for High-performance Supercapatteries

The designing of higher dimensional multifunctional architecture is an attractive feature to boost the electrochemical performance of the electrodes. Herein, bimetallic 3D-NiOCo3O4/Ni positive electrode is prepared via a facile electrodeposition route followed by a post-annealingmethod. Likewise, the 3D porous ϒ-Fe4NC@Ni/SS negative electrode is successfully developed through vapour phase growth process. The as-prepared 3D-NiOCo3O4/Ni demonstrate a high specific capacity of 98.92 mC cm−2 than 30.92 and 22 mC cm−2 of NiO and Co3O4, respectively. Furthermore, the 3D-ϒ-Fe4NC@Ni/SS electrode is delivered an areal capacitance of 125 mF cm−2. Moreover, enhanced electrochemical performance is observed for the assembled 3D-NiOCo3O4/Ni//3D-ϒ-Fe4NC@Ni/SS supercapattery enactment of individual electrodes. It is demonstrated a maximum energy density of 100.47 mWh cm−3 at a power density of 14.69 W cm−3 and 87% capacitance retention combined with 100% coulombic efficiency after 20,000 operation cycles. The attained results are witnessed the successful fabrication of 3D porous template with bimetallic involvement as well as the 3D-ϒ-Fe4NC nanostructure, easy ion penetration, and shorter diffusion path length. Additionally, the present outcome reveal the binder-free growth of both the battery-type and capacitive electrodes for the next-generation energy storage devices.

Stainless Steel/Hydroxyl Functionalized Graphene Electrode for Electrochemical Oxidation of Methyl Orange

Graphene and its related compounds are among the emerging materials to be studied for many applications, especially for the electrochemical process. We prepared a stainless steel/hydroxyl functionalized graphene (SS/G-OH) electrode by anodic electrodeposition method. The G-OH dispersion is realized with a voltage of 30 V for electrodeposition variation time 1, 3, and 5 min with 316L stainless steel as an anode and cathode. The obtained SS/G-OH electrode was characterized by XRD, SEM-EDX, and FTIR. The G-OH modified SS electrode shows higher electrocatalytic ability than that of the bare SS electrode. The best electrodeposition time is 3 min. The electrochemical degradation of 20 ppm methyl orange (MO) by using the SS/G-OH electrode with an applied current of 1.5 A showed a concentration reduction of >99% after 30 min of reaction. The GC data suggest that MO was mainly degraded to CO2and H2O. This graphene-based electrode could be of choice for the electrochemical degradation of industrial dyes.

Performance analysis of copper-based MWCNT composite coated 316L SS tool in electro discharge machining

The tool material properties are essential key factors for the enhancement of electro discharge machining performance mainly, resistance to the wear of tool, removal of material from workpiece, and machined surface quality. In this study, copper-based multi-wall carbon nanotube (MWCNT) composite coated 316 L stainless steel electrode was fabricated by electrodeposition method and used in EDM operation for investigating machining performance. The agglomeration problem of MWCNTs was a critical issue for fabrication copper matrix composite, which was addressed with a cationic dispersing agent. The copper-based MWCNT composite coated electrode was used for machining of 304 SS workpiece. The experimental results show 57.11% reduction of tool wear rate (TWR) and 99.52% improvement of material removal rate (MRR) for copper-based MWCNT composite coated electrode compared to pure copper coated 316 L SS electrode. The enhancement of surface quality was also observed for the machined surface, which was generated during the machining with copper-based MWCNT composite coated electrode. The micro-crack formation was almost eliminated by using copper-based MWCNT composite coated electrode, which will enhance the strength and fatigue property of machined component. The enhancement of micro-hardness was also observed for the machined surface.

Effect of electrodes on microsecond explosion of thin metal wires in vacuum

An order of magnitude difference was observed in the energy deposition during a microsecond explosion of thin nickel wires in a vacuum, depending on the design of the wire-holding electrodes. In one case, cylindrical polished stainless steel (ss) electrodes with a rounded edge have a small axial hole of 0.3 mm to hold a thin wire. In the second case, these were the same polished electrodes without an axial hole, and the wire was attached to the side of the electrode with a kapton tape. For the electrodes with an axial hole, a voltage breakdown appears when the wire reaches a low temperature of ∼570 K due to the generation of the parasitic plasma discharges from the wire-holder contact. In a long timescale of ∼30 μs, wire resistive heating was interrupted by plasma generations 6 times up to the moment of melting. For the same electrodes without holes, the wire reaches a temperature of ∼1870 K during an ∼2 μs single-stage heating, and the shunting plasma was generated due to the evaporation of impurities from the hot metal surface and avalanche ionization by thermo-emitted electrons from the hot metal surface. We observe similar effects for Cu, Ti, and Pt wires. This effect is important for slow microsecond exploding wires in a vacuum and negligible for fast nanosecond explosions.

Poly(o-aminobenzyl alcohol) Films with and without Organic Compound on AISI 316 Surface; Synthesis and the Corrosion Performances

In this work, it was studied to obtain the anticorrosive properties of polymer films (SS/PABA and SS/PABA-ORG) synthesized on stainless steel surface by adding an organic substance to aniline derived o-aminobenzyl alcohol monomer synthesis medium. Firstly, polymer coating bath was prepared by dissolving 0.15 M o -aminobenzyl alcohol monomer in electrolyte solvent containing acetonitrile and 0.15 M LiClO4. From this bath, poly (o-aminobenzyl alcohol) (PABA) film was synthesized in 30 segments by a cyclic voltammetry (CV) technique at a scanning rate of 50 mV/s at a potential range of -0.20/1.80 V on the AISI 316 (SS) working electrode in contrast to the platinum electrode. For the synthesis of organic structure doped polymer film (PABA-ORG), the same synthesis process was repeated by dissolving C21H27NO2(k) (ORG) at low concentration in the same bath. Corrosion performances of bare SS, SS/PABA and SS/PABA-ORG substrates were investigated using open circuit potential – time, anodic polarization and AC impedance techniques in corrosive solution. As a result of the study, it was observed that the organic additive added to the synthesis medium caused changes in the synthesis behavior of PABA. Corrosion performance tests showed that PABA and PABA-ORG films increased the corrosion protection performance of SS electrode and it was observed to reduce the corrosion rate of SS electrode.

Sterilization of Microorganisms Contaminated Surfaces and its Treatment with Dielectric Barrier Discharge Plasma.

Dielectric barrier discharge (DBD) is a promising method of producing non-thermal plasma, which is widely used in variety of industrial and biological applications including disinfection/sterilization. Plasma sterilization offers a faster, less toxic and versatile alternative to conventional sterilization techniques. 45 kV, 50 kHz high voltage high-frequency power supply was designed for generating DBD plasma. Experimental studies were conducted using DBD plasma on growth control in algae, breakdown of complex phenols for chemical wastewater treatment and generation of UV, ozone and other reactive species using DBD plasma discharges in ambient air. A portable DBD plasma-based sterilization system is developed for fighting the Covid-19 pandemic. Quartz tube is used as a dielectric medium between copper foil—SS electrodes and 17 kV, 30 kHz pulse is applied across it, which produces intense DBD across SS mesh. This system can sterilize and disinfect the microorganism contaminated surfaces, garments and used disposable protective gears with UV, ozone and short-lived molecules of metastable states and excited chemical species of nitrogen and oxygen produced during the DBD plasma discharges in ambient air.

Electrodeposited NiSe on a forest of carbon nanotubes as a free-standing electrode for hybrid supercapacitors and overall water splitting

NiSe nanoparticles are electrodeposited over a forest of carbon nanotubes (CNTs) to form an intertwined and porous network. The assynthesized composite (denoted as CNT@NiSe/SS) is used as a free-standing and multifunctional electrode for bothsupercapacitorsand overallwater splitting applications. For a supercapacitor application, CNT@NiSe/SS exhibits higher specific capacity and improved rate capability compared with individual NiSe and CNTs. A hybrid supercapacitor device consisting of battery-like CNT@NiSe/SS and EDLC-like graphene delivers a maximum energy density of 32.1 Wh kg−1 at a power density of 823 W kg−1 and has excellent stability after a floating test of 50 h. On the other hand, CNT@NiSe/SS also serves as a bifunctional electrocatalyst with high activity for overall water splitting. The CNT@NiSe/SS electrode displays excellent hydrogen and oxygen evolution reaction performance with the lowest overpotential of 174 mV at 10 mA cm−2 and 267 mV at 50 mA cm−2, respectively. The symmetrical two-electrode system requires an operating potential of 1.71 V to achieve a current density of 10 mA cm−2. Furthermore, this electrolyzer shows a negligible increment in potential after 24 hof continuouswater splitting. The outstanding performances of CNT@NiSe/SS can be attributed to the synergistic effect of NiSe and CNTs.

Treatment of phenol formaldehyde production wastewater by electrooxidation-electrofenton successive processes

ABSTRACT Treatments of phenol formaldehyde producing wastewater (PFPW) by electrooxidation (EO) and electro-Fenton (EF) successive processes were carried out in a batch electrolytic reactor using graphite (Gr) and stainless steel (Ss) electrodes. After the completion of the EO process, the wastewater was further treated with EF process. The influence of operating variables such as current density, operating time, initial pHi and H2O2 concentration was evaluated for removals of phenol, TOC and COD in PFPW. Gr/Gr, Gr/Ss or Ss/Ss and Ss/Gr electrode pair were used as anode and cathode. The best removal efficiency in the EO process was obtained with Gr/Gr (93%) as compared to Gr/Ss (82%), Ss/Ss (63%) and Ss/Gr (55%). The removal efficiencies for the EO process using Gr-Gr electrode pair were obtained as 93% for phenol, 61% for COD and 44% for TOC at initial pHi 7,5 g/L of NaCl, 50 mA/cm2 and 5 h. In the EF process, the removal efficiencies at pHi 3,5 mA/cm2 and 30 mM H2O2 and 45 min were 100% for phenol, 76% for COD and 59% for TOC. This study provided that the successive processes are an effective method for the removal of phenolic compounds from the wastewater.

Electrochemical Behavior of Electrode Materials (Nickel and Stainless Steels) for Sudomotor Dysfunction Applications: A Review

AbstractThis is an overview of the electrochemical characterization of nickel and stainless steel (so‐called SS) as electrodes in medical devices for the early diagnosis of small fiber neuropathy that originates from type‐2 diabetes or cystic fibrosis. The electrical current responses obtained during the clinical tests are related to the amount of chloride present on the sweat. SS electrodes are now used to replace nickel because this later not only presents problems with chloride sensitivity but its contact with skin can cause possible allergic reactions for some patients. For the above reasons, several types of SS were studied. It was shown that some of them perform well and have lower costs than Ni electrodes. We discuss the state of the art of the electrochemical studies conducted with nickel and steels under physiological or biomimetic conditions and discuss the advantages of a particular steel over the others depending on the conditions, especially chloride concentration.

Enhanced Anti-corrosive Properties of Electrosynthesized Polyaniline/zeolite Nanocomposite Coatings on Steel

The preparation of polyaniline/zeolite nanocomposite coating on 304 stainless steel (304 SS) surface has studied via the galvanostatic method. The electro-generated coating was characterized by Fourier transform infrared spectroscopy (FT-IR), UV-visible absorption spectroscopy, X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM). The anticorrosion property of polyaniline/zeolite nanocomposite coating was explored in 0.5 M hydrochloric acid solution by Tafel polarization method and electrochemical impedance spectroscopy (EIS). The effect of variable parameters such as the applied current density and deposition time on the corrosion protection of the electro-generated coatings was also considered. The corrosion rate of coated-304 SS was releazied about 36 times lower than bare 304 SS. Potential of corrosion also changed from -0.411 V to -0.279 V versus Ag/AgCl for un-coated and coated-304 SS electrodes, respectively. Electrochemical measurements indicate that polyaniline/zeolite nanocomposite coated on 304 SS has remarkable inhibitive properties with protection effectiveness of ~97% at 2.5 mA cm-2 current density used on 304 SS in acidic medium. The outcomes of this research obviously find out that the polyaniline/zeolite nanocomposite has an outstanding possible to defend 304 SS against corrosion in an acid environment.

Probing mechanisms for microbial extracellular electron transfer (EET) using electrochemical and microscopic characterisations

Microbial fuel cell (MFC) is a bioreactor and a power generator that directly converts chemical energy (i.e. organic-inorganic matters in wastewater) to electrical energy through the metabolic activity of the microorganisms. This not only helps cutting the energy costs but also accomplishes wastewater treatment simultaneously. A MFC system has a high efficiency in wastewater treatment; still, an amount of power generated is extremely low and insufficient to power even a pumping unit in the system. One of the key factors to the power generation is the electrochemically active microorganisms that are effective in electron transfer to a solid anode. However, the exact mechanisms by which electrons are transferred between the electrode surface and the microbial metabolism still remain unclear. This work, therefore, aimed to experimentally define the possible mechanism(s) of microbial extracellular electron transfer (EET) that governs the anodic reaction efficiency through the simultaneous investigations of cell voltage, power generation and %COD removal at different inoculation/immobilisation time (t). Ex situ microbial inoculation was initially performed to investigate the microbial growth rate and growth behaviour under simulated MFC conditions using mixed microbial cultures, obtained from an up-flow anaerobic sludge blanket at Cho-heng rice vermicelli industry, Thailand. This preliminary study directed towards the optimal conditions for in situ microbial inoculation/immobilisation in a mediator- and membrane-less MFC reactor built-in house. The effect of each EET mechanism on the production of electric current was assessed at different growth states by electrochemical characterisations (including cyclic voltammetry and electrochemical impedance spectroscopy (EIS)). The cyclic voltammograms of the microbe suspension with or without the presence of soluble electron shuttle confirmed that the microbes themselves were relatively inactive to respire solid electron acceptors through the direct electron transfer (DET) via the OM cytochromes but required exogenous/endogenous mediators to carry electrons from the microbes by diffusive transport to the electrode surface. That was an explanation why the microbe-free medium exhibited superior electrochemical activity in comparison with other microbial components (including medium-free inoculum and inoculated SS mesh electrode) for the first 80 h of inoculation. The peak current was increased with the presence of extracellular biofilm matrix on the electrode surface at longer t (i.e. t = 7 and 14 days) when the extent of biofilm formation on electrode surface was found to increase in the microscopic level as visualised by environmental scanning electron microscopy (ESEM). The EIS results also suggested that the charge transfer resistance between the electrode surface and microbial metabolisms decreased greatly with the extent of biofilm coverage. Hence, the corresponding MFC performance including maximum power density and %COD removal was maximised to 465 mW cm−3 and 100% respectively at t = 7 days once the EET mechanism was mainly driven by DET via the extracellular biofilm matrix corresponding with the highest current response of inoculated SS electrode in the LSCV measurement. However, the depletion of fresh nutrient under a closed-loop and continuous MFC operation resulted in the reduction of power output dramatically to 186 mW cm−3 at the end of experimental period (t = 12 days). The MFC performance could be maintained at its maximum values under realistic MFC operation with an opened-loop and continuous feeding mode which would be contributed to the development of an economical and commercially viable MFC in the future.

Electrochemical degradation of scarlet red dye from aqueous environment by titanium-based dimensionally stable anodes with SS electrodes

Textile effluents are toxic and carcinogenic materials that exist in the aquatic environment. In this study, the degradation efficiency of commercially available scarlet red dye investigated on TSA-SS Electro Fenton process (EFP) was reported. It is of great interest in the field of environmental engineering to remove dyes from aquatic environment. The influence of operating parameters such as pH (2–9), current density (0.1–0.5 mA/cm2), concentration of dye (0.1–0.5 g/L), H2O2 (0.1–0.5 g/L) concentration and Fe2+ concentration (0.01–0.03 g/L) were analyzed by batch system. The optimum degradation conditions were determined as pH—3, current density—0.4 mA/cm2, concentration of dye—0.4 g/L, H2O2 concentration—0.5 g/L and Fe2+ concentration—0.025 g/L. These results indicated that the degradation efficiency of scarlet red dye by EFP depends on solution pH and Fenton reagent concentration and a low pH value was favorable for the dye degradation. It has been demonstrated that more than 94% dye removal was obtained at 50 min. Electro Fenton process was also investigated by cyclic voltammetry technologies.

Chronoamperometric and chronopotentiometric investigation of Kraft black liquor

Black liquor is an effluent of pulp and paper mills. The electrolysis of Kraft black liquor is drawing high attention, as it leads to lignin recovery by anodic electrodeposition and cathodic production of hydrogen. However, the lignin oxidation process on black liquor is still poorly understood, requiring further fundamental studies to allow its comprehension. Therefore, detailed electrochemical studies are being carried out on the topic, which will allow a deeper insight in the involved electrode processes. The Kraft black liquor is physicochemically characterised, with the determined high values of pH, conductivity and lignin content (12.4, 460 mS cm−1 and 48.8 g dm−3, respectively) demonstrating the suitability of black liquor as an electrolyte medium. Voltammetry, chronoamperometry (CA) and chronopotentiometry (CP) techniques are done in black liquor solutions using Pt, Ni and AISI 304 SS electrodes to investigate the lignin oxidation process. The number of exchanged electrons is determined for each electrode material from CA and CP measurements using classic Cottrell and Sand analyses, respectively, with the faradic efficiency of Ni being close to that of Pt. The low-cost and high efficiency suggest Ni as a promising electrode material for application in black liquor electrolysers.

Electrosynthesis of Poly(ortho-phenetidine) Coatings on Steel and Investigation of Their Corrosion Protection Properties

Poly(ortho-phenetidine) coatings on 304 stainless steel (304 SS) surface have been synthesized by using the galvanostatic technique. The electrosynthesized coatings were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), UV-visible absorption spectrometry and Scanning Electron Microscopy (SEM). The anticorrosion performances of poly(ortho-phenetidine) coatings were examined in 0.1 M HCl medium by the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technique. The corrosion rate of poly(ortho-phenetidine)-coated 304 SS was found ~10 times lower than bare 304 SS and corrosion potential increased from –0.29 V for uncoated 304 SS to –0.19 V versus Ag/AgCl (3 M KCl) for poly(ortho-phenetidine)-coated 304 SS electrode. Electrochemical measurements indicate that poly(ortho-phenetidine) coating has good inhibiting properties with an efficiency of ~93% at 1.5 mA cm–2 applied current density in acidic corrosive media. The results of this study obviously ascertain that the poly(ortho-phenetidine) has an outstanding potential to protect 304 SS against corrosion in an acidic environment.