Portugaliae Electrochimica Acta最新文献

{"title":"Synthesis and Characterization of Heparin-Doped Polypyrrole Coatings Using an Electrochemical Quartz Crystal Microbalance (EQCM)","authors":"D. Flamini, M. B. González, S. Saidman","doi":"10.4152/pea.2022400104","DOIUrl":"https://doi.org/10.4152/pea.2022400104","url":null,"abstract":"Polypyrrole (PPy) films were electrochemically synthesized on an Au/TiO 2 coated quartz crystal electrode in solutions with different heparin (Hep) concentrations. The PPy films morphology was determined by tapping a mode atomic force microscopy (AFM). The influence of the dopant concentration on the coating surface roughness was studied. Electrochemical quartz crystal microbalance (EQCM) results suggest that Hep retained in the PPy films was bound to thrombin. The adsorbed thrombin amount increased with a higher coating surface roughness. PPy films doped with Hep are electroactive and show cation exchange properties under oxidation or reduction conditions in a Ringer solution. The pre-oxidized PPy film adsorbed a greater thrombin amount than the freshly one and even more than the pre-reduced film.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isoproturon (IPU) Electrochemical Sensing Based on a Polymethylmethacrylate Ferrite (PMMA/M(FexOy)) Nanocomposite Modified Electrode","authors":"S. Mehtab, M. Zaidi, P. Bhatt, P. Joshi, T. Agarwal","doi":"10.4152/pea.2022400305","DOIUrl":"https://doi.org/10.4152/pea.2022400305","url":null,"abstract":"The use of pesticides has been increased in recent years, to enhance crops productivity, which may lead to a serious global concern of environmental pesticides monitoring. Isoproturon (IPU: 3-(4-isopropylphenyl)-1,1-dimethylurea) is an herbicide widely used in wheat crops. However, when it enters in the ecosystem, it is heavily toxic to humans. Thus, there is an urgent need to develop sensitive and selective IPU detection methods. In the present work, a novel polymethylmethacrylate/ferrite (PMMA/M(FexOy)) polymer nanocomposite (PNC) modified glassy carbon electrode (GCE) was developed for IPU detection. The PNC/GCE surface morphology was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). PNC electrochemical characterization (EC) was performed by cyclic voltammetry (CV) that showed a quasi-reversible redox behavior. PNC/GCE demonstrated an excellent square wave voltammetric (SWV) response towards IPU, with a limit of quantification (LOQ) of 1.98 × 10 M, and a limit of detection (LOD) of 6.5 × 10 M, in 1 M HClO4 (perchloric acid), at pH 2.0. EC investigations reflected a peak current that was linearly related to IPU concentrations, with a high detection sensitivity. It also showed much better CV and SWV IPU responses than those of a bare GCE, and further environmental stability, without a high influence of common interfering ions.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Corrosion Inhibition of Mild Steel in a Phosphoric Acid Solution of a Novel Benzothiazine Derivative","authors":"A. El-khlifi, M. Saadouni, R. Ijoub, A. Oubihi, Y. ElAoufir, S. Boukhriss, M. Ouhssine","doi":"10.4152/pea.2022400103","DOIUrl":"https://doi.org/10.4152/pea.2022400103","url":null,"abstract":"Ethyl 3-hydroxy-2-(p-tolyl)-3,4-dihydro-2H-benzo[b][1,4]thiazine-3-carboxylate (EHBT) inhibition effect and its adsorption onto a mild steel surface in phosphoric acid (2 M H 3 PO 4 ) was investigated, at temperatures varying between 298 and 328 K, by weight loss, EIS and potentiodynamic polarization techniques. The tested compound showed an inhibition efficiency that was superior to 88 % for a concentration equal to 5 × 10 -3 M. Polarization measurements indicated that the examined EHBT acted as a mixed inhibitor. The protection efficiency increased with higher inhibitor concentrations and decreased with an increase in temperature. EHBT adsorption onto the mild steel surface obeyed Langmuir adsorption isotherm. EHBT inhibition action was also evaluated by surface SEM images.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Olive Mill Wastewater Removal by H3PO4 Treated Olive Stones as an Efficient Adsorbent and Electrocoagulation Process","authors":"W. Yassine, S. Akazdam, I. Mechnou, Y. Raji, S. Zyade","doi":"10.4152/pea.2022400601","DOIUrl":"https://doi.org/10.4152/pea.2022400601","url":null,"abstract":"Olive mill wastewater (OMW) is the major problem from olive oil extraction, due to its polluting organic and mineral matter and acid pH. This study aims to electrochemically treat OMW in an Al electrode reactor, to oxidize the organic matter, discolor the margins and neutralize the pH, thus reducing the pollutants. Various low cost adsorbents have been studied for the treatment of different types of effluents. In this study, the potential of activated carbon (C) derived from olive stones (OS) was studied for OMW removal. H 3 PO 4 (phosphoric acid) treated OS (AOS), as a low-cost, natural and eco-friendly biosorbent, was investigated for OMW removal from aqueous solutions. This work found that the increase in electrolysis time and current intensity significantly improved the treatment, while energy consumption and electrodes were observed. The results showed thirty-fold diluted margins for effluents with an acid pH of 5.02 and a conductivity of 14.89. The physicochemical parameters evolution during the electrocoagulation (EC) treatment showed that, under the conditions of an electrolysis time of 3 h and a current intensity of 3 A (= 416 A/m -2 ), the margins discoloration diluted ten times (91%), the mass loss of the electrodes was 0.55 kg.m -3 and the chemical oxygen demand (COD) reduction was 50%. These optimal operational levels allowed a good degradation of the margins. Biosorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The experimental isotherm data were analyzed using Langmuir’s and Freundlich’s isotherms equations. The best fit was obtained by the Langmuir’s model, with maximum OWM monolayer biosorption capacity of 189.83 mg/g. The biosorption was exothermic in nature (entalphy change:  H° = -13.11 kJ/mol). The reaction was accompanied by a decrease in entropy (  S° = -72.91 kJ/mol). The Gibbs energy (  G°) was higher when the temperature was increased from 303 to 318 K, indicating a decrease in the biosorption feasibility at higher temperatures. The results have established good potentiality for EC and ALS to be used for OMW removal.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70921430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevention of Mild Steel Corrosion in Potable Water by an Environmentally Friendly Inhibitor","authors":"N. Suma","doi":"10.4152/pea.2022400204","DOIUrl":"https://doi.org/10.4152/pea.2022400204","url":null,"abstract":"Green corrosion inhibitors find various applications in the field of corrosion engineering and technology. In the present work, powder forms of Pimenta Dioica leaves were added into corrosion media to study their effect. Mild steel coupons corrosion studies showed an increase in the inhibitor efficiency, at higher concentrations, in corrosive media. The coupons electrochemical behavior was studied by OCP measurements. P. Dioica inhibition efficiency, adsorbed layers mechanism and mild steel corrosion rate were analyzed using weight loss measurements.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption Properties and Electrochemical Behavior of Thymus Willdenowii Boiss and Reut Essential Oil as a Green Inhibitor for Mild Steel Corrosion in 1 M HCl","authors":"M. Ouknin, P. Ponthiaux, J. Costa, L. Majidi","doi":"10.4152/pea.2022400101","DOIUrl":"https://doi.org/10.4152/pea.2022400101","url":null,"abstract":"The inhibition effect of Thymus willdenowii Boiss & Reut essential oil (TW) on the mild steel corrosion in 1 M HCl has been investigated using weight loss measurements, surface analysis (SEM-EDX, three-dimensional profilometry and FT-IR), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The TW oil anticorrosion effect was evaluated using polarization potentiodynamic curves obtained after 30, 60 and 90 min of immersion in a 1 M HCl medium. Gravimetric results have shown that TW oil has a significant inhibition efficiency value of 81.42%, which was attained at 3 g/L. The polarization measurements have shown that TW is a mixed type inhibitor, with a significant reduction in cathodic and anodic current densities. Measurements by electrochemical impedance spectroscopy revealed that resistance to the charge transfer has increased with higher TW oil concentrations. From the use of SEM-EDX and three-dimensional profilometry, it is clear that the metal surface has remarkably improved in the TW oil presence, compared to the one exposed to the acid medium without essential oil. From the TW proprieties and the obtained results, it can be concluded that this oil is a new natural substance that can be used against material corrosion in aggressive solutions.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70919307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Graphene Oxide-Aryl Substituted Triazole Thin Hybrid Corrosion Resistant Coating for Copper","authors":"N. Arshad, M. Imran, M. Akram, F. Altaf","doi":"10.4152/pea.2022400304","DOIUrl":"https://doi.org/10.4152/pea.2022400304","url":null,"abstract":"A graphene oxide-triazole hybrid anti-corrosive coating was done by fabricating a triazole derivative – 2-(5-mercapto-4-((3-nitrophenyl)amino)-4H-1,2,4-triazol-3-yl)isoindoline-1,3-dione (4-NBT) on a graphene oxide (GO) coated Cu electrode. The GO-4-NBT hybrid coating effect on the Cu surface corrosion behavior was electrochemically monitored through cyclic voltammetry (CV), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The fabrication of a protective coating was done in two steps. Firstly, GO was electrochemically deposited on the Cu electrode in two different aggressive media (1 M HCl and 0.1 M Na 2 SO 4 ), separately. Secondly, different 4-NBT concentrations were employed to reinforce GO corrosion resistant properties. CV studies revealed that GO-4-NBT effectively suppressed the metal oxidation and oxygen reduction. EIS studies suggested that the electrochemical process on the Cu surface with GO and GO-4-NBT was charge transfer controlled. The corrosion inhibition efficiency (IE) measured by PDP and EIS was enhanced with a related raise in 4-NBT concentration. Electrochemical studies revealed that the GO-4-NBT was a mixed type of inhibitor that predominantly inhibited the anodic reaction, especially in the case of 0.1 M Na 2 SO 4 . Adsorption studies further indicated the involvement of a stable and spontaneous adsorption mechanism, most probably by chemisorption. GO-4-NBT has shown significant corrosion protection activity in 0.1 M Na 2 SO 4. and EIS, and adsorption studies.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Selective PVC Matrix Assisted Potentiometric Sensor for the Determination of Hydroxyzine Hydrochloride (HDH)","authors":"R. N. Prasad, C. Siddaraju","doi":"10.4152/pea.2022400503","DOIUrl":"https://doi.org/10.4152/pea.2022400503","url":null,"abstract":"A membrane sensor using an ion association complex of hydroxyzine hydrochloride (HDH) with Orange II (ORG-II) dye, in a polyvinyl chloride (PVC) matrix, has been developed and used as a selective electrode for HDH quantification in pharmaceuticals. The sensor is suitable to determine 2.2 × 10 -5 - 1.1 × 10 -3 mol L -1 HDH, in the pH range from 2.5 to 5.21, with the Nernstian slope of 57.41±1.04 mV/decade, under optimum conditions. The regression coefficient (RC) value of 0.999 shows a good correlation between HDH concentration and the potential measured using the proposed sensor. The sensor limit of detection (LOD) was 4.5 × 10 -6 M. A standard-addition procedure was followed to study the effect of various interferents. The results revealed no variations caused by foreign ions or species. The regression equation (RE) and relative standard deviation (RSD) values, from 1.67 to 5, and from 1.86 to 4.81%, respectively, indicated the HDH-ORG sensor acceptable accuracy and precision. The RSD values of ≤5.67 and <5% indicated the sensor acceptable robustness and ruggedness, respectively. It has been successfully used to determine HDH in tablets, and excellent results were obtained.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applications of Pyrrole Based Molecularly Imprinted Polymers as Analytical Sensors: a Review","authors":"N. Rajendraprasad","doi":"10.4152/pea.2022400404","DOIUrl":"https://doi.org/10.4152/pea.2022400404","url":null,"abstract":"Molecularly imprinted polymers (MIPs) are an important class of compounds with wider sensing applications for the determination of substances ranging from small molecular masses to macro size. The hyphenation of MIP principle with other likewise conducting polymers yields the devices for sensing purposes. MIPs are robust against environmental conditions, more economical than natural receptors, and their preparation is also adequate for substances without natural receptors. Organic mediated MIPs compounds are of current interest, due to their applicability as quantification tools to determine electroactive substances in a variety of real samples. MIPs are highly selective for target molecules, mechanically strong, resistant to temperature and pressure, inert towards acids, bases, metal ions and organic solvents, highly stable for longer periods, and operative at room-temperature. Therefore, during past years, MIPs have been used as electrochemical and optical sensors, sorbents, solid phase media, and so on. Herein, there is a focus on the use of Pyrrole (Py) as a monomeric molecule to fabricate MIPs. Py or poly-Py (p-Py) based MIPs are synthesized and used in various capacities as chemo electrochemical sensors. A detailed discussion on the application of Py-mediated MIPs for the electrochemical determination of some organic compounds of therapeutic and environmental interest is herein presented as a review.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70920782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the Deterioration of Galvanized Steel in an Acidic Medium using Pinus Oocarpa Seed Extract as Inhibitor","authors":"M. O. Nkiko","doi":"10.4152/pea.2022400202","DOIUrl":"https://doi.org/10.4152/pea.2022400202","url":null,"abstract":"Pinus oocarpa seed extract corrosion inhibition effect on galvanized steel has been studied in 2 M hydrochloric acid, at 303 K and 333 K, by gravimetric methods. The inhibitor efficiency decreased with higher temperatures, which suggests physisorption. Potassium iodide (KI) synergistic action produced an increase in the extract inhibition efficiency, but its parameter decreased with higher inhibitor concentrations. The galvanized steel optical microscopy shows that the metal surface was coated with P. oocarpa seed extract, and that the cracks observed in the inhibitor absence were filled. This observation suggests that the extract can be used as a coating to prevent galvanized steel corrosion.","PeriodicalId":20334,"journal":{"name":"Portugaliae Electrochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70919797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}