Article
Environmental Sciences
Yaswanth K. Penke, Amit K. Yadav, Iram Malik, Alekha Tyagi, Janakarajan Ramkumar, Kamal K. Kar
Summary: Understanding mechanistic insights in environmental remediation and mitigation systems has garnered increased attention. The study confirms the effectiveness of CAF-rGO hybrid in arsenic adsorption/electrosorption mechanisms, with potential implications for arsenic mitigation applications.
Article
Chemistry, Multidisciplinary
Vaidish Sumaria, Philippe Sautet
Summary: Step and kink sites on Pt surfaces play a crucial role in determining the adsorption structure of CO under ambient conditions. Both the step structure and the arrangement of CO molecules on the step influence the organization of CO molecules on the lower terrace. Different types of steps lead to diverse adsorption configurations of CO on the terrace.
Article
Chemistry, Physical
P. M. Pasinetti, Veronica Paz Zanini, A. J. Ramirez-Pastor, O. A. Pinto
Summary: In this study, deposition phenomena on a modified electrode were investigated within the framework of mean field theory. The effects of impurities and lateral interactions between particles were considered, with analysis based on adsorption isotherms and voltammograms. The potential and limitations of the analytical approximation were discussed by comparing theoretical predictions with Monte Carlo simulations and experimental measurements.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Analytical
Lanting Qian, Abigail van Riesen, Joshua van der Zalm, Richard Manderville, Aicheng Chen
Summary: Investigations on the electrochemical behaviors of merocyanine dyes revealed their strong dependence on the type of electrode used, as well as the presence of substituent functional groups. The inclusion of these functional groups led to reduced fouling and affected electron transfer kinetics. Understanding the influence of substituents allows for the design and synthesis of aptamer-binding merocyanine dyes for highly robust and sensitive electrochemical sensors in medical and environmental applications.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Jonathan A. Mwanda, Angel Cuesta
Summary: This study investigated the electrochemical reduction of Ag+ on a cyanide-modified electrode, revealing the formation of an AgPt surface alloy on the platinum substrate without loss of the cyanide adlayer. The large negative shift of the Ag+/Ag redox couple was attributed to the strong affinity of Ag+ for the CN adlayer. Additionally, electrodeposited Ag could be reoxidized to yield Ag+ coordinated to the CN adlayer, leading to surface roughening and gradual transformation of the cyanide-modified Pt(111) to a cyanide-modified AgPt surface alloy on Pt(111) with successive cycling below 0.90 V.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Meng Li, Matthew T. Curnan, Wissam A. Saidi, Judith C. Yang
Summary: Understanding the influence of defects on oxidation is crucial for the applications of nano-oxides in catalysis, electronics, and corrosion. This study investigates the uneven surface oxidation induced by surface steps on copper materials using atomic-scale in situ environmental transmission electron microscopy experiments. The results provide mechanistic explanations for the observed formation site preferences, which vary with surface orientation and oxygen concentration, based on Ehrlich-Schwobel barrier differences for oxygen diffusion on stepped surfaces.
Article
Chemistry, Multidisciplinary
Anni Yu, Ruben Rizo, Francisco J. Vidal-Iglesias, Rosa M. Aran-Ais, Yan-Xia Chen, Enrique Herrero, Juan M. Feliu
Summary: Information on the chemical adsorption and surface oxidation of Ru under electrochemical conditions is crucial for understanding the structure-activity relationship in Ru-based materials. This study investigates the adsorption of hydrogen and oxygen species on quasi-single-crystalline Ru films on Pt(111) electrodes. The formation of Ru-O and the conversion to RuO2 were observed at specific potentials. These findings provide insights into the electrochemical properties and ligand effects of Ru.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Jagdish C. Bhangoji, Christopher J. Barile, Suresh S. Shendage
Summary: A simple and environmentally-friendly approach was developed to synthesize 2D CuO nanosheets using electrochemical deposition. The formed nanosheets exhibit advantageous properties such as no toxicity, high electrical conductivity, and a p-type semiconducting nature with a band gap of 1.2 eV. These nanosheets were used to construct a sensitive electrochemical sensor for glucose detection, which displayed excellent sensitivity, wide linear range, and low limit of detection. The high electrocatalytic performance of the sensor is attributed to the unique structural morphology and high conductivity of the CuO nanosheets.
Article
Electrochemistry
Qian Song, Hui Li, Junji Liu, Shi Hu
Summary: Cyclic voltammetry (CV) was used to study the electrochemical deposition of selenium (Se) on carbon black-supported Pt nanostructures, showing different behavior on cubic and octahedral Pt nanocrystals supported by carbon.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2021)
Article
Chemistry, Physical
Intissar Kherbach, Victor Climent, Juan M. Feliu
Summary: The rate of CO formation from CO2 reduction on Pt(111) vicinal surfaces with (100) steps was studied using cyclic voltammetry. Selective modification of step sites with bismuth or copper revealed two different mechanistic regimes depending on the potential range. In the high potential region, CO2 is activated on steps and protonated by Solution protons, while in the low potential region, activated CO2 reacts with adsorbed hydrogen. The presence of copper on steps increases the activity in the high potential region but does not affect CO formation in the low potential region.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Zhutian Ding, Annabella Selloni
Summary: In this study, the solvation structure of flat and stepped MgO(001) in neutral liquid water was investigated using ab initio molecular dynamics. Water dissociation fractions were found to be >20% and >30% on the flat and stepped surfaces, respectively. Additionally, metastable OH groups perpendicular to the interface were observed slightly above the first water layer.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Andrey Yasinskiy, Sai Krishna Padamata, Srecko Stopic, Dominic Feldhaus, Dmitriy Varyukhin, Bernd Friedrich, Peter Polyakov
Summary: The study investigated the electrochemical decomposition of spent catalyst in molten salts for the extraction of precious metals, focusing on aluminum electrowinning from xLiF-(1-x)AlF3 melts. The results revealed a diffusion-controlled two-step process with both one-electron and two-electron reductions occurring simultaneously at close potentials. Further research is needed to optimize the process parameters for aluminum reduction during catalyst treatment and primary metal production.
Article
Chemistry, Analytical
Gisele A. B. Mello, Valentin Briega-Martos, Juan M. Feliu
Summary: This study investigates the sensitivity of glucose oxidation reaction on different surface structures of magnesium alloys. The results show that the surface structure has a significant impact on the reaction, and different structures lead to different reaction pathways, thus affecting the catalytic activity of the reaction.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Jessica Jein White, Jack Jon Hinsch, William W. Bennett, Yun Wang
Summary: In this study, the adsorption properties of water on stable stepped Fe(2 1 0) and Fe(2 1 1) surfaces were investigated using density functional theory. The results revealed that water has a stronger interaction on surface Fe atoms with lower coordination numbers, and the stepped surface can facilitate water dissociation by reducing dissociation energy barriers. This study suggests that passivation of the stepped surface can improve the performance of nZVI.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Analytical
Vinicius Del Colle, Gabriel Melle, Bruno A. F. Previdello, Juan M. Feliu, Hamilton Varela, Germano Tremiliosi-Filho
Summary: The influence of (bi)sulfate anion on the electro-oxidation of glycerol on Pt(hkl) surfaces was studied. The results showed that stepped surfaces and Pt(1 1 0) exhibited higher catalytic activity in high concentration sulfuric acid solution, and the presence of (1 1 0) step sites influenced the oscillatory behavior.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Jose M. Gisbert-Gonzalez, William Cheuquepan, Adolfo Ferre-Vilaplana, Enrique Herrero, Juan M. Feliu
Summary: Adsorbed amino acids can modulate the behavior of metal nanoparticles in advanced applications through interactions with surfaces. The adsorption behavior of glutamate on Au(111) surface is influenced by solution pH and surface charge. Glutamate adsorption involves deprotonation of carboxylic groups and bonding in a bidentate configuration. The oxidation of glutamate only occurs on an oxidized surface, involving the transfer of an oxygen group while the main chain remains intact according to FTIR spectra.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Electrochemistry
Rodolfo M. Antoniassi, Heiki Erikson, Jose Solla-Gullon, Roberto M. Torresi, Juan M. Feliu
Summary: By controlling the shape, metal nanoparticles can be significantly improved for electrocatalysis, but overcoming limitations from large particle size is necessary for practical applications, where nanoparticles should be smaller than 5 nm. Researchers synthesized 3-5 nm cubic Pt nanoparticles with about 40% preferential {100} structure on the surface.
Article
Electrochemistry
Jose M. Gisbert-Gonzalez, Maria V. Oliver-Pardo, Valentin Briega-Martos, Juan M. Feliu, Enrique Herrero
Summary: The behavior of adsorbed CTAB on Au(111) electrodes was studied using electrochemical and FTIR experiments in different aqueous solutions. The results showed that the adsorbed layer was stable in acidic solutions. Changes in electrode charge led to changes in electrode capacitance, resulting in characteristic peaks.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Physical
Valentin Briega-Martos, William Cheuquepan, Juan M. Feliu
Summary: In this study, in situ external infrared reflection absorption spectroscopy (IRRAS) was used to detect intermediate species in the ORR mechanism on a flat and well-defined Pt surface. The main ORR-generated intermediate, O-2(-), was identified near the Pt surface in experimental conditions with limited reactivity, allowing for its detection without the use of additional signal enhancement methods.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Review
Chemistry, Physical
Camilo A. Angelucci, Janaina Souza-Garcia, Juan M. Feliu
Summary: The use of single crystal electrodes as model catalysts is widely applied for studying reaction mechanisms. Changes in the surface structure and electronic properties affect adsorption energy, thus impacting catalytic activity. The influence of adsorbed species depends on surface structure, species nature, and the studied reaction.
CURRENT OPINION IN ELECTROCHEMISTRY
(2021)
Article
Electrochemistry
Jose M. Gisbert-Gonzalez, Maria Oliver-Pardo, Francisco J. Sarabia, Victor Climent, Juan M. Feliu, Enrique Herrero
Summary: This study investigated the adsorption behavior of CTAB and CTAOH on gold single crystal electrodes in solutions with different pH values. The stability and composition of the adsorbed adlayer were found to vary with changes in surface charge.
ELECTROCHIMICA ACTA
(2021)
Article
Electrochemistry
R. Martinez-Hincapie, A. Rodes, V Climent, J. M. Feliu
Summary: This study investigates the in-situ spectro-electrochemical behavior of Pt(110) electrodes in contact with acid solutions saturated with CO2, finding potential-dependent signals associated with adsorbed bicarbonate and carbonate anions. The relative intensities of infrared bands at different pH and applied potential values can be used to determine the interfacial pK(a),(2) of CO2. The surface pK(a),(2) value for Pt(110) electrodes is lower than that of Pt(111) electrodes, attributed to differences in surface structure and reactivity.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Physical
Ruben Rizo, Juan M. Feliu, Enrique Herrero
Summary: The HPRR on Pt surfaces was studied at pH = 13, showing that Pt(1 1 1) is the most active surface, but its activity decreases with the introduction of steps. Inhibition of HPRR was observed at low potentials, with the onset potential controlled by OHads and the point of maximum entropy. Experiments with different rotation rates suggested the formation of an HPRR intermediate linked to the inhibition process.
JOURNAL OF CATALYSIS
(2021)
Article
Electrochemistry
Madis Lusi, Heiki Erikson, Kaido Tammeveski, Alexey Treshchalov, Arvo Kikas, Helle-Mai Piirsoo, Vambola Kisand, Aile Tamm, Jaan Aruvali, Jose Solla-Gullon, Juan M. Feliu
Summary: The study evaluated three mesoporous nitrogen-doped carbon support materials for oxygen reduction reaction, compared to Vulcan carbon, in 0.1 M KOH and 0.5 M H2SO4 solutions. Palladium nanoparticles were synthesised using the citrate method and the average particle size was determined. The unique porosities of the ECS were evaluated using the BET method, showing similar microporosity but varying mesopore distribution.
ELECTROCHIMICA ACTA
(2021)
Article
Electrochemistry
Andrea Auer, Francisco J. Sarabia, Christoph Griesser, Victor Climent, Juan M. Feliu, Julia Kunze-Liebhaeuser
Summary: Modifying Cu(111) electrodes with different foreign metals or metal hydroxides can significantly influence the electrocatalytic activity for the hydrogen evolution reaction, with Ni(OH)2 and Co(OH)2 enhancements and Cd decreases observed.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Physical
Luis E. Botello, V. Climent, J. M. Feliu
Summary: This study focuses on the thermodynamic characteristics of the hydrogen underpotential deposition process on Pt(111) in alkaline media, with a specific emphasis on hydrogen adsorption and its impact on hydrogen evolution.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Frederic Stein, Sebastian Kohsakowski, Ricardo Martinez-Hincapie, Sven Reichenberger, Christoph Rehbock, Viktor Colic, Daniel Guay, Stephan Barcikowski
Summary: The catalytic activity and toxicity of mixed-metal nanoparticles depend on their surface composition. This study analyzed the electrochemical properties and redox chemistry of different gold-silver alloy nanoparticles with varying gold content. The results showed that the surface gold content influenced the oxygen reduction reaction and the stability of the particles. XPS analysis revealed the accumulation of the minor constituent on the surface of the alloy nanoparticles. The equimolar Au50Ag50 composition exhibited particularly low reactivity and high chemical stability.
FARADAY DISCUSSIONS
(2023)
Article
Engineering, Chemical
Ricardo Martinez-Hincapie, Viktor Colic
Summary: This review discusses recent advances in the application of complex alloy materials such as high-entropy alloys (HEAs) for the oxygen reduction reaction, and explores the existing experimental challenges in benchmarking the electrocatalytic properties of these materials.
Article
Chemistry, Physical
Ariadna Segundo-Aguilar, Linda V. Gonzalez-Gutierrez, Victor Climent Paya, Juan Feliu, German Buitron, Bibiana Cercado
Summary: The study conducted simultaneous dual production of gaseous biofuels in a two-chamber MEC fed with digester effluents, testing different combinations of biomass content and cell voltage to produce biogas and hydrogen simultaneously. The data generated showed the energy efficiency and economic benefits of this system.
SUSTAINABLE ENERGY & FUELS
(2021)