Potential Electrolysis Research Articles

Examination of fecal electrolyte on pediatric patient with intestinal stoma

Intestinal stomas are increasingly performed in pediatric patients to manage various gastrointestinal conditions, such as congenital malformation of intestinal, necrotizing enterocolitis and intestinal obstruction, which are frequently occured in developing countries with Low-Middle Income Country (LMIC). However, the presence of a stoma has possibility of morbidity such as can significantly affect the body’s fluid and electrolyte balance, particularly in infant and under five years old children. This risk is increased due to the immature renal system in pediatric patients, increased loss of fluids and electrolytes through stoma output, especially small intestinal stoma. In addition to being a challenge in the management of infants and children with stomas and intestinal resections, electrolyte imbalances are one of the factors contributing to morbidity and mortality in these group. Early detection of abnormalities can guide timely interventions such as fluid replacement therapy and dietary modifications, prevent complications like dehydration, metabolic acidosis or electrolyte disturbances. Measuring fecal electrolyte provide valuable insights into the patient’s hydration status and potential electrolyte imbalances. Since the fecal sample measuring is the simplest, harmless and noninvasive than the other electrolyte tests, so it can be considered for pediatric patients.

Electrochemical CO2 Reduction Using a New Ru‐NAD Type Bis Carbonyl Complex

A new ruthenium(II) NAD (NAD = Nicotinamide Adenine Dinucleotide) type bis‐carbonyl complex, [Ru(bpy)(pbn)(CO)2]2+ [pbn = 2‐(pyridin‐2‐yl)benzo[b]‐1,5‐naphthyridine; bpy = 2,2'‐bipyridine] [1]2+, was successfully synthesized and fully characterized by single‐crystal X‐ray structural analysis, ESI‐MS, IR and NMR spectroscopy. Complex [1]2+ together with [Ru(bpy)(pbn)(CO)(COOH)]+ and/or [Ru(bpy)(pbn) (CO)(CO2)]0 complexes exist as equilibrium mixtures in aqueous solutions as evident from spectroscopic study. Chemical reduction of [1]2+ resulted the formation corresponding NADH form i.e., [Ru(bpy)(pbnHH)(CO)2]2+ (pbnHH = 2‐(pyridin‐2‐yl)‐5,10‐dihydrobenzo[b][1,5]naphthyridine) [1.HH]2+ as a two‐electron‐reduced species. The electrochemical behavior of complex [1]2+ in the presence of acid was investigated based on cyclic voltammetry analysis. A control potential electrolysis of [1]2+ afforded formate (HCOO‐) as the major product with a lesser amount of CO and H2, whereas that of [Ru(bpy)2(CO)2]2+ complex produced CO as the main product with a lesser amount of HCOO‐ and H2. The experimental results suggest that the selectivity of HCOO‐ over CO should be due to catalytic hydride transfer from the NADH‐type ligands of [1]2+ to CO2.

Regioselective Electrochemical Construction of Csp2−Csp2 Linkage at C5−C5’ Position of 2‐Oxindoles via an Intermolecular Anodic Dehydrogenative Coupling

AbstractApplying electricity as a reagent in synthetic organic chemistry has attracted particular attention from synthetic chemists worldwide as an environmentally benign and cost‐effective technique. Herein, we report the construction of the Csp2−Csp2 linkage at the C5−C5’ position of 2‐oxindole utilizing electricity as the traceless oxidant in an anodic dehydrogenative homo‐coupling process. A variety of 3,3‐disubstituted‐2‐oxindoles were subjected to dimerization, achieving yields of up to 70 % through controlled potential electrolysis at an applied potential of 1.5 V versus Ag/Ag+ nonaqueous reference electrode. This electro‐synthetic approach facilitates the specific assembly of C5−C5’ (para‐para coupled) dimer of 3,3‐disubstituted‐2‐oxindole without the necessity of any external oxidants or additives and DFT (Density Functional Theory) calculations provided confirmation of this pronounced regioselectivity. Furthermore, validation through control experiments and voltammetric analyses substantiated the manifestation of radical‐radical coupling (or biradical pathway) for the dimerization process.

Deciphering Electrocatalytic Hydrogen Production in Water Through a Bioinspired Water-Stable Copper(II) Complex Adorned with (N2S2)-Donor Sites.

Electrocatalytic hydrogen production stands as a pivotal cornerstone in ushering the revolutionary era of the hydrogen economy. With a keen focus on emulating the significance of hydrogenase-like active sites in sustainable H2 generation, a meticulously designed and water-stable copper(II) complex, [Cl-Cu-LN2S2]ClO4, featuring the N,S-type ligand, LN2S2 (2,2'-((butane-2,3-diylbis(sulfanediyl))bis(methylene))dipyridine), has been crafted and assessed for its prowess in electrocatalytic H2 production in water, leveraging acetic acid as a proton source. The molecular catalyst, adopting a square pyramidal coordination geometry, undergoes -Cl substitution by H2O during electrochemical conditions yielding [H2O-Cu-LN2S2]2+ as the true catalyst, showcases outstanding activity in electrochemical proton reduction in acidic water, achieving an impressive rate of 241.75 s-1 for hydrogen generation. Controlled potential electrolysis at -1.2 V vs. Ag/AgCl for 1.6 h reveals a high turnover number of 73.06 with a commendable Faradic efficiency of 94.2 %. A comprehensive analysis encompassing electrochemical, spectroscopic, and analytical methods reveals an insignificant degradation of the molecular catalyst. However, the post-CPE electrocatalyst, present in the solution domain, signifies the coveted stability and effective activity under the specified electrochemical conditions. The synergy of electrochemical, spectroscopic, and computational studies endorses the proton-electron coupling mediated catalytic pathways, affirming the viability of sustainable hydrogen production.

Oxygen Defect Site Filling Strategy Induced Moderate Enrichment of Reactants for Efficient Electrocatalytic Biomass Upgrading.

The electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) provides a feasible approach for the efficient utilization of biomass. Defect regulation is an effective strategy in the field of biomass upgrading to enhance the adsorption capacity of reactants and thus increase the activity. However, how to select appropriate strategies to regulate the over-enrichment of reactants induced by excessive oxygen vacancy is still a huge challenge. In this work, the defect-filling strategy to design and construct an element-filled oxygen vacancy site layered double hydroxide (S─Ov─LDH) is adopted, which achieves a significant reduction in the electrolysis potential of biomass platform molecule HMF oxidation reaction and a significant increase in current density. Physical characterizations, electrochemical measurements, and theoretical calculations prove that the formation of metal─S bond in the second shell effectively regulates the electronic structure of the material, thus weakening the over-strong adsorption of HMF and OH- induced by excessive oxygen vacancy, promoting the formation of high-valence Co3+ during the reaction, and forming new adsorption sites. This work discusses the catalytic enhancement mechanism of defect filling in detail, fills the gap of defect filling in the field of biomass upgrading, and provides favorable guidance for the further development of defect regulation strategies.

Corrolato(oxo)antimony(V) Dimer with Hydrogen-Bond Donor Groups in Secondary Coordination Sphere as a Catalyst for Hydrogen Evolution Reaction.

The focus is on developing alternative molecular catalysts using main-group elements and implementing strategic improvements for sustainable hydrogen production. For this purpose, a FB corrole with a (2-(2-((4-methylphenyl)sulfonamido)ethoxy)phenyl) group inserted into the meso position (C-10) of the corrole, along with its high-valent (corrolato)(oxo)antimony(V) dimer, was synthesized. In the crystal structure analysis of the FB corrole and the (corrolato)(oxo)antimony(V) dimer complex, it was noted that the sulfonamido group in the ligand periphery sits atop the corrole ring. The electrochemical hydrogen evolution reaction (HER) of the (corrolato)(oxo)antimony(V) dimer was studied and compared with a previously reported (corrolato)(oxo)antimony(V) complex, which lacks hydrogen-bond donor groups in the secondary coordination sphere. The newly designed molecules, featuring hydrogen-bond donor groups in the secondary coordination sphere, demonstrated clear superiority in the electrochemical HER. Controlled potential electrolysis was employed to evaluate the charge accumulation associated with hydrogen generation in a homogeneous three-electrode system in the presence of 50 mM TFA. The produced hydrogen exhibits a Faradaic efficiency of approximately 80.96%, a turnover frequency (TOF) of 0.44 h-1, and a production rate of 52.83 μL h-1, highlighting the effective catalytic activity of the (corrolato)(oxo)antimony(V) dimer in hydrogen evolution.

Probing the Molecular Interactions of Electrochemically Reduced Vitamin B2 with CO2.

The electrochemical reduction of riboflavin (vitamin B2) in a dimethyl sulfoxide solvent was examined under a CO2 atmosphere and compared with results under an argon atmosphere. Variable-scan-rate cyclic voltammetry combined with controlled potential electrolysis (CPE) and analysis by UV-vis and EPR spectroscopies provided insights into the nature of interactions of reduced flavins with dissolved CO2. Reductive exhaustive CPE experiments under CO2 indicated an overall two-electron stoichiometry, compared to one-electron reduction under an argon atmosphere, due to the lowering of the formal one-electron reduction potential of the flavin radical anion to form the dianion, which can be rationalized by riboflavin-CO2 molecular interactions. UV-vis spectroscopic measurements confirmed complete chemical reversibility of the redox transformations over extended time scales. Digital simulation modeling of the voltammetric data enabled extraction of thermodynamic and kinetic parameters for the proposed mechanism, comprising multiple proton-coupled electron transfer steps, diamagnetic anions, radical anions, and neutral radical intermediates enroute to the fully reduced state, as well as evidence of a long-lived solution phase complex of the reduced riboflavin with CO2.

Study on electrochemical anodization initiation and progression of binderless tungsten carbide (WC) through experimentation and simulation

This article explores the electrochemical anodization of binderless tungsten carbide (WC) using computational simulations and experimental methods. It aims to comprehend the complex relationship between anodization time, surface roughness, elemental composition, and current behavior on polished and non-polished substrates. COMSOL Multiphysics models provide the initial findings by meticulously mapping the electrolyte's potential and the current density vectors. These simulations reveal the fundamental electrochemical behaviors anticipated during anodization, particularly emphasizing the regions near the anode expected to undergo anodization. Experimental observations confirm the simulation results, showcasing how non-polished WC surfaces, replete with inherent imperfections, undergo anodization characterized by fluctuating current densities and compositional changes, highlighting the profound influence of surface defects on electrochemical processes. On the other hand, when WC substrates are polished, they show a more consistent and controlled anodization process. This suggests a close connection between the occurrence of anodization and the surface treatment, ultimately influencing the effectiveness of anodization. This comprehensive study, which combines simulation and experimentation, greatly enhances the understanding of the electrochemical anodization of WC. It suggests potential methods for enhancing surface modifications to expand the range of applications for WC, particularly in precision glass molding, aerospace, and medical industries.

A Low-Cost and Green Zinc-Iron Battery Achieved by Ethaline Deep Eutectic Solvent.

Deep eutectic solvents (DESs) were considered as a potential electrolyte because of their low price, harmless to environment and wider electrochemical window potential compared to water. In this work, Fe(III)/Fe(II) and Zn(II)/Zn redox couples were used as the positive and negative active materials, respectively, in a DES system using choline chloride and ethylene glycol in a molar ratio of 1 : 2 (ethaline). The possible working mechanism of the battery was studied by cyclic voltammetry, spectroscopic and simulation methods. The effects of different temperatures, concentrations of zinc ions in the anolyte and current densities on battery performance were evaluated. The results showed that the designed zinc-iron battery should preferably be operated at a current density of 0.5 mA cm-2 and the temperature of 313~323 K, which will improve the energy efficiency and maintain a high coulombic efficiency. The variation of cycle performance test presents a different pattern from the usual batteries, which is due to the effect of RO- group. At 313 K and 0.5 mA cm-2, the coulombic efficiency increases from 14.1 % to 100.2 % after 46 cycles, and then remains at about 100 % during the rest 54 cycles, which demonstrates a good cycle stability of DES-based zinc-iron battery.

A Voltage-Controlled Strategy for Modular Shono-Type Amination.

Shono-type oxidation to generate functionalized heterocycles is a powerful method for late-stage diversification of relevant pharmacophores; however, development beyond oxygen-based nucleophiles remains underdeveloped. The limited scope can often be ascribed to constant current electrolysis resulting in potential drifts that oxidize a desired nucleophilic partner. Herein, we report a voltage-controlled strategy to selectively oxidize a broad scope of substrates, enabling modular C-N bond formation from protected amine nucleophiles. We implement an electroanalytically guided workflow using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) to identify oxidation potentials across a range of heterocyclic substrates. Controlled potential electrolysis (CPE) selectively generates α-functionalized C-N products in moderate to good yields using carbamate-, sulfonamide-, and benzamide-derived nucleophiles. The importance of voltage control is further exemplified through a systematic study comparing our developed CPE method to constant current electrolysis (CCE) protocols. Voltage-guided CCE and traditionally optimized CCE reveal the importance of maintaining voltage control for high yields and selectivity over a broad scope; a case study with a morpholine-derived substrate illustrates the negative impact of potential drifting under CCE. Sulfonamide drugs, which have significant oxidation potential overlap with model substrates, are rendered competent nucleophiles under CPE. Lastly, sequential voltage-controlled C-N and C-O functionalization of a model substrate generates difunctionalized pyrrolidines further broadening the utility of this reaction.

Influence of Surfaces on Ion Transport and Stability in Antiperovskite Solid Electrolytes at the Atomic Scale.

Antiperovskites are generating considerable interest as potential solid electrolyte materials for solid-state batteries because of their promising ionic conductivity, wide electrochemical windows, stability, chemical diversity and tunability, and low cost. Despite this, there is a surprising lack of a systematic study of antiperovskite surfaces and their influence on the performance of these materials in energy storage applications. This is rectified here by providing a comprehensive density functional theory investigation of the surfaces of M3OX (M = Li or Na; X = Cl or Br) antiperovskites. Specifically, we focus on the stability, electronic structure, defect chemistry, and ion transport properties of stable antiperovskite surfaces and how these contribute to the overall performance and suitability of these materials as solid electrolytes. The findings presented here provide critical insights for the design of antiperovskite surfaces that are both stable and promote ion transport in solid-state batteries.

Synthesis of a Hematite‐Geopolymer Composite: Optimization of Formulation Parameters and Application to the Detection of Pb2+ Ions in Aqueous Solution

AbstractThe Composite Centered Experimental Design (CCED) using the response surface methodology was used to optimize the synthesis of a hematite‐geopolymer composite, applied to the preparation of a Pb2+ electrochemical sensor. Two important experimental parameters in the formulation (curing time and hematite content) were considered in the optimization of the synthesis of the composite material. The electrochemical signal of Pb2+ at a carbon paste electrode modified by the synthesized composite was used as a response to identify the best formulation. After applying the generated experimental plan, the optimal composite material was obtained using 17.08% hematite and a curing time of 0.16 days. The characterization of the optimized composite material revealed the presence of a porous structure and a poly(phospho‐ferro‐siloxo) network, but with a fraction of well dispersed and unreacted hematite. Preliminary experiments confirmed that the sensor prepared with the composite showed high stability and reproducibility of the Pb (II) signal, justifying its application for accurate sensing of the metal cation in an aqueous solution. A Pb2+ calibration curve was obtained after optimizing the experimental detection parameters (composition of the carbon paste electrode, pH of the accumulation solution, accumulation time, and electrolysis potential). A detection limit of 0.2 nM (based on a signal‐to‐noise ratio of 3) was obtained for a studied concentration range between 0.04 and 0.48 nM. The designed sensor also showed remarkable selectivity and excellent performance in real media samples (spring, tap, rain, and well water).

NaZr2(PO4)3 - a cubic langbeinite-type sodium-ion solid conductor.

The synthesis of langbeinite-type phosphates with small cations such as Li+ or Na+via a high-temperature solid-state reaction is a challenging task due to the predominant formation of a related NaSICON-type phase. This work reports on the synthesis route, crystal structure, thermal behavior, and Na-conductive properties of the langbeinite-type NaZr2(PO4)3 prepared by a mechanochemically activated ion-exchange reaction between hydrothermally prepared NH4Zr2(PO4)3 and NaNO3. The crystal structure of NaZr2(PO4)3 is refined based on X-ray diffraction data and validated by Fourier-transformed infrared spectroscopy. NaZr2(PO4)3 is found to be stable up to 730 °C, undergoing a transformation into the NaSICON phase with further heating. Notably, in the 25-500 °C range, the material shows negative thermal expansion. The Na+ conductivity within the range of 50-225 °C amounts to 1.7 × 10-8 S cm-1 at 50 °C and 1 × 10-6 S cm-1 at 225 °C with an activation energy of 0.44 eV, accompanied by a sufficiently low (∼10-12 S cm-1) electronic conductivity. The bandgap of 4.44 eV and the electrochemical stability window covering the 1.39-4.18 V vs. Na/Na+ range are calculated using density functional theory. The obtained results open up opportunities for designing langbeinite-structured phosphates as potential solid electrolytes for Na-ion batteries.

Synergistic Electronic and Carbonyl Proximity Effects in Electrochemical Hydrogen Evolution Catalyzed by Tetrakis(ethoxycarbonyl)porphyrin Metal Complexes

Electrocatalytic properties of a series of tetrakis(ethoxycarbonyl)porphyrin (TECP) 3d-metal complexes, and the influence of ester groups on the hydrogen evolution reaction (HER), were investigated using trifluoroacetic acid in a 0.1 M [Bu4N]PF6 DMF solution. [Co(TECP)], [Ni(TECP)], and [Cu(TECP)] exhibited three redox couples, with reversibility decreasing at more negative potentials. The third reduction couple was predominantly ligand-centered. Upon addition of TFA, the second reduction waves became catalytic, increasing proportionally with TFA concentration, indicating that the molecular nature of the [M(TECP)] complexes plays a role in facilitating HER. Electrochemical and catalytic studies revealed that [Cu(TECP)] demonstrated the highest Faradaic efficiency (FE) of 98% and the lowest overpotential (0.7 V) while maintaining strong acid tolerance. [Co(TECP)] became effective at overpotentials exceeding 800 mV, suggesting the predominance of EECC pathway at more negative potential. The roles of the ester groups extended beyond a simple inductive effect, as confirmed by controlled potential electrolysis and spectroelectrochemical analyses. The superior HER activity of [Cu(TECP)] compared to [Cu(TPrP)] and [Cu(TPP)] highlights the contribution of the carbonyl groups to catalytic performance. This work underscores the importance of ester groups placement within the porphyrin framework and suggests that meso-ester groups can influence both the stability and catalytic performance, paving the way for further investigations.

Influence of Mg2+ doping on the oxide ion conductivity of layered ferroelectric SrBi2Ta2O9

Layered perovskites structures are an interesting candidate to explore as a potential electrolyte materials for Solid oxide fuel cell (SOFC) applications. However, achieving a high ionic conductivity (∼0.01 S cm⁻1 below 650 °C) remains a significant challenge to lowering the SOFC operating temperatures. SrBi2Ta2O9 (SBT), an Aurivillius-based layered perovskite, is a well-known ferroelectric material with TC of 320 °C. Site exchange and Bi volatility related defects lead to ionic conductivity in SBT above 700 °C. Here, we aim to control the defect chemistry by doping to promote the oxygen vacancies. We show that Mg doping at the Ta-site in the perovskite block results in 4-fold increase in the bulk conductivity of SBT 3.65 × 10−4 S cm−1 and improvement in the ionic transport number from 0.26 to 0.71. The study provides an opportunity to design new oxide ion conductors in layered ferroelectric oxides.

Anodic Dissolution of Al–Fe and Al-Fe-Si Alloys in Emimcl–AlCl3 Electrolyte

To produce over 99.9% of high-purity Al from Al–Fe alloy containing Al6Fe and Al–Fe–Si alloy containing β-AlFeSi by electrorefining, their anodic dissolution and cathodic electrodeposition characteristics were investigated in an EmImCl–AlCl3 ionic liquid electrolyte at 323 K. Constant potential electrolysis showed that Fe dissolved from Al–Fe anode at 0.7 V vs Al/Al(III) and from Al–Fe–Si anode at 1.4 V, and was co-deposited with Al on the cathode. Notably, anodic dissolution potential of Fe was changed by forming β-AlFeSi, and Si did not dissolve from β-AlFeSi at either potential. A combination of controlled anodic dissolution potential and the use of the Al alloy containing β-AlFeSi further suppressed the dissolution and cathodic co-deposition of Fe, affording high-purity Al on the cathode.

Phosphate Ion-Selective Electrode Based on Electrochemically Modified Iron.

The significance of the detection of phosphate ions is immense in the realms of chemistry, biology, medicine, environment, and industry. The detection of phosphate ions is currently mainly reliant on blue molybdenum colorimetry, which is accurate but requires sample pretreatment, intricate operation, and a high price tag. Consequently, it is essential to create a sensor with superior efficiency, precision, straightforward functioning, and instantaneous online detection. This study has designed and created an electrochemical modification based on an iron metal electrode for this purpose. Cyclic voltammetry was used to initially ascertain the potential (-0.57 V) necessary for constant potential electrolysis. Employing a constant potential electrolysis method, the iron oxide and its phosphate were modified onto the surface of the iron electrode to enable reaction with phosphate ions. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to characterize and analyze the morphology and elemental composition of Fe-PME, elucidating how it responds to phosphate ionation. The two-electrode system was then utilized for the evaluation of the phosphate ion response of Fe-PME at pH 4. Fe-PME's response to phosphate ions is demonstrated by the results, ranging from 10-5 to 0.1 M and with a slope of -52.8 mV dec-1. Fe-PME exhibited satisfactory results when compared to the conventional blue colorimetry of molybdenum.

Heterometallic Transition Metal Oxides Containing Lewis Acids as Molecular Catalysts for the Reduction of Carbon Dioxide to Carbon Monoxide with Bimodal Activity.

Electrocatalytic CO2 reduction (e-CO2RR) to CO is replete with challenges including the need to carry out e-CO2RR at low overpotentials. Previously, a tricopper-substituted polyoxometalate was shown to reduce CO2 to CO with a very high faradaic efficiency albeit at -2.5 V versus Fc/Fc+. It is now demonstrated that introducing a nonredox metal Lewis acid, preferably GaIII, as a binding site for CO2 in the first coordination sphere of the polyoxometalate, forming heterometallic polyoxometalates, e.g., [SiCuIIFeIIIGaIII(H2O)3W9O37]8-, leads to bimodal activity optimal both at -2.5 and -1.5 V versus Fc/Fc+; reactivity at -1.5 V being at an overpotential of ∼150 mV. These results were observed by cyclic voltammetry and quantitative controlled potential electrolysis where high faradaic efficiency and chemoselectivity were obtained at -2.5 and -1.5 V. A reaction with 13CO2 revealed that CO2 disproportionation did not occur at -1.5 V. EPR spectroscopy showed reduction, first of CuII to CuI and FeIII to FeII and then reduction of a tungsten atom (WVI to WV) in the polyoxometalate framework. IR spectroscopy showed that CO2 binds to [SiCuIIFeIIIGaIII(H2O)3W9O37]8- before reduction. In situ electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) with pulsed potential modulated excitation revealed different observable intermediate species at -2.5 and -1.5 V. DFT calculations explained the CV, the formation of possible activated CO2 species at both -2.5 and -1.5 V through series of electron transfer, proton-coupled electron transfer, protonation and CO2 binding steps, the active site for reduction, and the role of protons in facilitating the reactions.

Simultaneous desalination and removal of organic pollutants in a novel bifunctional FCDI system: The enhancement by in-situ reutilization of chloride ions

A new system of flow electrode capacitive deionization coupled with in situ electro-oxidation (FCDI-EO) was constructed to achieve the degradation of organic pollutants while maintaining high desalination efficiency. The effects of different parameters of potential difference, electrolyte, and pH on the chloride removal performance of FCDI-EO and the removal performance of rhodamine B (RhB) were investigated. Under the optimal conditions of potential difference = 4 V, [Cl−] = 500 mg/L, and pH = 4, the removal of chloride ions, RhB and total organic carbon (TOC) was as high as 88.74 %, 99.02 %, and 87.82 %, respectively. The quenching experiments showed that hydroxyl radicals (OH) and reactive chlorine species (RCS) were involved in the FCDI-EO system. The liquid chromatography-mass spectrometry (LC-MS) analysis suggested the possible mineralization pathway of RhB. Furthermore, toxicity assessment analysis showed that the toxicity of the degradation intermediates of RhB decreased during the treatment. Overall, this study provides a promising process that reducing the generation of high-concentration saline water in desalination and in situ utilizing the Cl− gathered from the feed water. The findings of this study could provide useful guidance for the development of flow electrode capacitive deionization technology and organic pollutant control.

Electrocatalytic reduction of protons with bis(N-para-carboxyphenyldithiocarbamato)-(1,10-phenanthroline) cobalt(II) and manganese(II) complexes

In this study, 1,10-phenanthroline adducts of bis(N-para-carboxyphenyldithiocarbamato)-cobalt (II) (1) and manganese (II) (2) possessing CoII/I and MnII/I redox couples at −1.56 and −1.57 V versus Ag/AgCl reference were carefully synthesized. These complexes are active for proton reduction at relatively low overpotentials of 0.12 – 0.32 V. Adduct 1 displayed metal-centered catalytic currents at −1.52, −1.58, −1.65, and −1.79 V at [TFA] of 1–4 mM culminating in an anodic shift of 40 mV and cathodic shifts of 20, 90, and 230 mV while adduct 2 displayed metal-centered catalytic currents at −1.53, −1.61, −1.85, and −1.89 V at [TFA] of 3–5 mM culminating in an anodic shift of 40 mV and cathodic shifts of 40, 280, and 320 mV. Experimental TOFs (kobs) of 2.02–4.54 s−1 were observed for the metal-centred processes while the foot-of-the-wave analysis (FOWA) which was used to examine the kinetics of electrocatalysis yielded theoretical TOFs of 0.45 and 0.92 s−1 that culminated in rate constants kcat of 757 and 1526 M−1s−1 for adducts 1 and 2 respectively. The controlled potential electrolysis produced TONs and Faradaic efficiencies in the range of 2.9–5.5 and 61–88 % respectively. The outstanding performances of the adducts offer promising prospects for the electrocatalytic reduction of protons.