bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ionic Distribution at the Ionic Liquid/Water Interface: An x-Ray Reflectometry Study
Authors: Nishi Naoya , Katakura Seiji , Sakka Tetsuo , Bu Wei , Lin Binhua , Schlossman Mark L 
Published: July 2021

Electrochemistry at ITIES, which has been extensively studied for the oil (O)/water(W) interface, has been extended to the liquid/liquid interfaces of ionic liquids (ILs), namely, to the IL/W interface [1] and even to the IL/O interface [2,3]. One of several characteristics of ILs, compared with conventional molecular liquids like W and O, is the formation of ionic multilayers [4-6] at the interfaces due to the excluded volume and local electrostatic interactions between ions. Although such a multilayering behavior of ILs had been expected to appear in the electric double layer (EDL) at the IL/W interface, it had been challenging to detect the ionic distribution at the IL/W interface.
In the present paper, we will introduce our recent study on the ionic distribution at the IL/W interface, revealed by x-ray reflectometry (XR) using the liquid surface reflectometer at NSF’s ChemMatCARS Sector 15-ID at Advanced Photon Source in Chicago [7]. We designed an ionic liquid that has both high hydrophobicity and high electron-density contrast between the cation and anion, which enabled us to widely polarize the IL/W interface and sensitively probe the cation-rich and anion-rich layers by XR, respectively. We observed the growth of alternately charged cation-rich and anion-rich layers along with a polarity reversal of the layers as the potential changed sign. We quantitatively compared the XR results with the BSK model [8], a phenomenological EDL model in ILs that takes into account both excluded volume and overscreening effects, by combining it with the Gouy-Chapman-Stern model for EDL on the W side of the IL/W interface. Our XR data reveal that the excess charge beyond the first ionic layer decays more rapidly than the model prediction, suggesting that the BSK model needs an improvement with which the layering periodicity and decay length are separately evaluated.
References

T. Kakiuchi and N. Nishi, Electrochemistry, 74 (2006) 942.

N.E.R. Cousens and A.R. Kucernak, Electrochem. Commun., 31 (2013) 63.

Y. Kuroyama, N. Nishi, T. Sakka, submitted.

N. Nishi, Y. Yasui, T. Uruga, H. Tanida, T. Yamada, S. Nakayama, H. Matsuoka, T. Kakiuchi, J. Chem. Phys., 132 (2010) 164705.

N. Nishi, T. Uruga, H. Tanida, T. Kakiuchi, Langmuir, 27 (2011) 7531.

N. Nishi, T. Uruga, H. Tanida, J. Electroanal. Chem., 759 (2015) 129.

S. Katakura, K. Amano, T. Sakka, W. Bu, B. Lin, M.L. Schlossman, N. Nishi, J. Phys. Chem. B, 124 (2020) 6412.

M.Z. Bazant, B.D. Storey, A.A. Kornyshev, Phys. Rev. Lett., 106 (2011) 046102.
Modulating the Pro-Apoptotic Activity of Cytochrome C at a Biomimetic Electrified Liquid|Liquid Interface
Authors: Gamero Daniel , Bhattacharya Shayon , Cazade Pierre-André , Molina-Osorio Andrés F. , Beecher Cillian , Djeghader Ahmed , Soulimane Tewfik , Dossot Manuel , Thompson Damien , Herzog Gregoire , Scanlon Micheal D. 
Published: July 2021

Programmed cell death via apoptosis is a natural defence against excessive cell division, crucial at all stages of life from foetal development to maintenance of homeostasis and elimination of precancerous and senescent cells.
In this presentation, an electrified liquid|liquid bio-interface is demonstrated that replicates the molecular machinery of the inner mitochondrial membrane at the onset of apoptosis. By mimicking in vivo cytochrome c (Cyt c) interactions with cell membranes, our platform allows us to modulate the conformational plasticity of the protein by simply varying the electrochemical environment at an aqueous|organic interface. Our experimental findings supported by molecular modelling show that adsorption, orientation, restructuring, and pro-apoptotic peroxidase activity of Cyt c can all be precisely manipulated. Remarkably, we observe interfacial electron transfer between an organic electron donor decamethylferrocene and O2, electrocatalysed by Cyt c. This interfacial reaction requires partial Cyt c unfolding, mimicking Cyt c
in vivo peroxidase activity.
Our electrified liquid|liquid bio-interface motivates development of biomimetic electrochemical platforms to identify drug molecules that can potentially downregulate Cyt c and protect against uncontrolled neuronal cell death in Alzheimer’s and other neurodegenerative diseases. As proof-of-concept, we demonstrate that bifonazole, predicted to target the heme pocket, inhibits the electrocatalytic activity of Cyt c and switches off O2 reduction.

Figure 1
Modification and Electrochemical Study of Dimensionally Stable Anodes for the Oxygen Evolution Reaction
Authors: Salverda Allison , Dondapati Jesse S. , Chen Aicheng 
Published: July 2021

In order to sustain and support the current level of economic growth, while addressing climate change issues, the development of clean and sustainable resources has become of the utmost importance in recent years. Potential resources such as oxygen and hydrogen can be produced from water electrolysis. There is a great interest in the development of advanced electrocatalysts for efficient water splitting [1,2]. Two-dimensional (2D) nanomaterials like graphene and graphene oxide (GO) can form thin layers on a supporting material for the transformation of properties and, as a result, can be exploited for efficient oxygen evolution reaction (OER) catalysts [3]. Previous research shows that noble metals tend to have a good catalytic activity for the OER; while another metal is added to further improve the electrochemical stability of the catalytic layer. By incorporation of a 2D graphene-based nanomaterial into an established OER electrocatalyst, there is significant potential to improve the OER catalytic activity and stability.
A tantalum iridium oxide (Ta2O5-IrO2) coating is considered to be one of the best electrocatalysts for the OER in acidic media. In the present study, novel Ta2O5-IrO2-rGO coatings with varying loads of reduced graphene oxide (rGO) were designed to investigate the effects of rGO on the catalytic activity and stability of the Ta2O5-IrO2 coating for the OER. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopy (EDS) were employed to characterize the morphology and composition of the prepared Ta2O5-IrO2-rGO coatings. Longevity tests revealed that the incorporation of rGO into the oxide layer strongly affected the stability of the Ta2O5-IrO2-rGO electrodes. The electrochemical activities of the prepared Ta2O5-IrO2-rGO electrodes were characterized by cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS). The effect of graphene-based nanomaterials on a Ta2O5-IrO2-rGO coating is compared and discussed.
[1] B. Sidhureddy, J. S. Dondapati, and A. Chen, Chem. Commun., 55, 3626 (2019).
[2] J. Cirone, S. R. Ahmed, P. C. Wood, and A. Chen, J. Phys. Chem. C, 123, 9183 (2019).
[3] A. Salverda, J.S. Dondapati, A. R. Thiruppathi, and A. Chen, J. Electrochem. Soc.,
167, 146506 (2020).
Dealloying Ni-Co-Se Electrocatalysts for Efficient and Stable Oxygen Evolution at High Current Densities
Authors: Abed Jehad , Thorpe Steven , Sargent Edward 
Published: July 2021

Stable and affordable electrocatalysts are urgently needed to accelerate the transition from conventional fossil fuels to sustainable energy resources such as solar and wind. Over the last two decades, the electrocatalytic splitting of water, and carbon dioxide reduction to hydrocarbons have received great attention, however approximately 90% of the electricity input is consumed at the anodic oxygen evolution reaction (OER) due to poor reaction kinetics. Precious metal-based electrocatalysts (Pt, Ir, Ru) have been commonly used as OER catalysts, but proven uneconomic for large scale industrial deployment. First-row transition metal elements (Ni, Co, Fe) offer a great earth abundant and low-cost alternative for OER.
In this work, we used a two-step novel milling process to produce Ni,Co-based nanocrystalline electrocatalysts. Cryo-milling (mechanical milling of precursors at cryogenic temperatures to achieve alloying) followed by surfactant-assisted ball milling (SABM), to reduce particles to nanoparticle, create stable disordered phases with high surface areas and coordinatively unsaturated active sites for the reaction of OER intermediates.
Two Ni-Co-Se alloys were milled under various conditions and the structural evolution of the systems was monitored using X-ray diffraction (XRD) and electron microscopy. Our results confirmed the production of two fully alloyed ternary systems (NiCo)3Se4 and (NiCo)Se after 6 hours of milling time. The electrocatalytic activity and stability of the catalysts were evaluated by Tafel measurements obtained from linear sweep voltammetry (LSV) and cyclic voltammetry (CV) experiments. We found that Se in NiCo-based alloys stabilized the disordered structure by forming non-transitional clusters and significantly facilitated the production of nanoparticles. In situ X-ray Absorption Spectroscopy (XAS) and electron microscopy revealed that Se was dealloyed during the OER reaction activating the electrocatalysts by facilitating the formation of active Ni-Co oxyhydroxides. On a glassy carbon electrode at 10 mA.cm-2, activated (NiCo)3Se4 demonstrated a stable performance for 500 hours at 268 mV overpotential with a Tafel slope of 42 mV.dec-1. Moreover, the the catalyst was stable for 100 hours while delivering 500 mA.cm-2 at 320 mV of overpotential. This work suggests that milling can potentially be used to produce OER catalysts for industrial application.
Modelling of Patterned Cathode-Membrane Interfaces with Random Roughness for PEMFCs
Authors: Eardley Sam , Andrews James , Du Shangfeng 
Published: July 2021

Proton Exchange Membrane fuel cells (PEMFCs) are becoming an increasingly promising piece of power generation technology that can fit into the changing economy as we strive towards a sustainable energy-based future. However, PEMFCs struggle to meet the energy demands of the world, falling short of the capability of other energy sources such as fossil fuels, mainly due to price and energy output compared to the already establish combustion engines. Looking internally into the PEMFC itself, one of the main issues is the limitations of the electrode-membrane interface leading to low ion transfer performance from the catalyst layer to polymer electrolyte membrane. If we can improve the cathode-membrane interface facilitating the oxygen reduction reaction (ORR) rate at the cathode, the rate limiting step, we can increase the overall performance of the fuel cell.
It is believed that by increasing the interfacial area of the cathode-membrane interface, such as applying a prismatic pattern to the morphology, we can increase the active surface area for the membrane electrode assembly (MEA). By varying the prism frequency and relative height, the interfacial area can be tuned to improve the overall power performance of PEMFCs.
In this work, with a LiveLink connection between Matlab and multiphysics software COMSOL, we model the electrode-membrane interface to investigate its influence on the ion-transfer performance of PEMFCs. By varying the number and size of prism peaks applied to the interface, it is shown that we can influence the fuel cell performance whilst maintaining a constant membrane and catalyst loading. The results showed, at an optimal peak frequency and relative height, an improvement of up to 25% was achieved in the power density.
Although research into the prismatic morphology looks promising, there are many other potential options when looking for which morphology could yield the best overall power performance out of a PEMFC. As such, looking not only into prismatic patterning, but also a pyramidal morphology could prove beneficial. We're also looking into how the application of the roughness to the interface, created using a combination of Gaussian and Uniform wave functions, will impact any previous results observed, and allow us to simulate a model that fits better with the real-world findings.

Figure 1
(Invited) Hybrid Electrocatalysts for Bioelectrooxidation of Small Alcohols: Ethanol and Ethylene Glycol
Authors: Honorio Franco Jefferson , Rodrigues Antônio Jesimiel G. Rodrigues , Minteer Shelley , Almeida Paula Z , Polizeli Maria Lourdes T. Moraes , De Andrade Adalgisa Rodrigues 
Published: July 2021

Over the last decades researchers have focused to enhance the electrocatalytic activity of the biosystems, increasing the energy generation and electronic conductivity into the biofilms. The use of enzymes immobilized onto the surface of electrodes as the main catalyst in biological fuel cells has been extensively reported. A biofuel cell provides a means to obtain clean, renewable energy and have great potential to be used as alternative energy source for low power devices. There still a lot of important issues in the development of these device, one of them, is to obtain the maximum energy from the fuel. In order to enhance the power density of enzymatic biofuel cell (EBFC) it is necessary to increase the degree of oxidation of the fuel, so that all the electrons from the fuel can be harvested. One approach is the immobilization of a group of enzymes to perform a cascade in order to maximize the fuel oxidation. Recently, we have concentrated our goal to the develop hybrid biofilms employing MWCNT in order to immobilize efficiently the enzymes. In this context we added organic catalyst (TEMPO (2,2,6,6- tetramethylpiperidin-1-yl) oxyl) or metallic nanoparticles (MWCNT/Pt, MWCNT/PtSn and MWCNT/Au) to the biofilms to create a hybrid catalytic system able to catalyze the complete electrooxidation of ethanol (ET) and ethylene glycol (EG) into CO2. In the case of ethanol extraction of 12 electrons per molecule at a single hybrid anode has been obtained with success. This simple methodology can replace the use of enzymatic cascade (7-8 enzymes) and may improve the application in biofuel cells. The electrochemical response of the enzyme system (MWCNT-COOH/LPEI/OxOx) at increasing concentrations of ethanol confirms the excellent activity of these hybrid bioanodes. Product analysis by HPLC techniques allowed us to correlate the increase in current with the formation of CO2or other more oxidable compounds as main product. In the case of EG the metallic catalyst was shifting the onset oxidation potential to lower potentials (200 mV) compared with TEMPO. The maximum power densities reached values around 351 µW cm-2 in the case of MWCNT/PtSn-OxOx for EG and 315 µW cm-2 for MWCNT-COOH/Pyrene-TEMPO/OxDc bioanode. Fig 1 show the products formed for EG. The modification of nanomaterials to obtain a large energy output form an enzymatic system will be highlighted. Therefore, the system open a new alternative of high performance hybrid-EBFC-based enabling the development of efficient EBFC based on alcohols.
Acknowledge: FAPESP (grants # 2017/20431-7 and 2014/50945-4 ), CNPq (grant (465571/2014-0) and CAPES 001. Army Research Office MURI (W911NF-14-1-0263).

Figure 1
(Invited) Hybridization of Molecular and Metallic/Semiconductor Materials for CO2 Catalytic Reduction
Authors: Robert Marc 
Published: July 2021

Reduction of carbon dioxide has as main objective the production of useful organic compounds and fuels - renewable fuels - in which solar energy would be stored. Molecular catalysts can be employed to reach this goal. They may in particular provide excellent selectivity thanks to easy tuning of the electronic properties at the metal and of the ligand second and third coordination sphere. Hybridization of these catalysts with conductive or semi-conductive materials may lead to enhance stability and new catalytic properties. This approach bridges between homogeneous and heterogeneous, and it raises new fundamental questions that may further lead to breakthrough in CO2 reduction chemistry.
Our recent results in this area will be discussed. [1-5]
References

M. Wang, L. Chen, T-C. Lau, M. Robert, Angew. Chem. Int. Ed.
2018, 57, 7769-7773.

S. Ren, D. Joulie, D. Salvatore, K. Torbensen, M. Wang, M. Robert, C. Berlinguette, Science
2019, 365, 367-369.

E. Boutin, M. Wang, J. C. Lin, M. Mesnage, D. Mendoza, B. Lassalle-Kaiser, C. Hahn, T. F. Jaramillo, M. Robert, Angew. Chem. Int. Ed.
2019, 58, 16172-16176.

B. Ma, G. Chen, C. Fave, L. Chen, R. Kuriki, K. Maeda, O. Ishitani, T-C. Lau, J. Bonin, M. Robert, J. Am.
Chem. Soc.
2020, 142, 6188-6195

P. B. Pati, E. Boutin, R. Wang, S. Diring, S. Jobic, N. Barreau, F. Odobel, M. Robert, Nat. Commun.
2020, 11:3499.
(Invited) Innovative Olivine Cathodes for High-Voltage and High-Rate Lithium Batteries
Authors: Vezzu Keti , Pagot Gioele , Negro Enrico , Di Noto Vito 
Published: July 2021

Lithium batteries (LiBs) are among the most promising systems that could address today’s strongly increasing needs for an efficient, compact and reversible electrochemical storage of energy [1]. Indeed, LiBs are characterized by a high specific capacity, a high efficiency, and a long lifespan [2]. Unfortunately, improvements in the working potential, in the specific energy, and in the rate capability properties of the cathodes are still needed to comply with the specifications required by practical applications.
This work describes the synthesis and the characterization of a new family of high-voltage and high-rate cathodes for LiBs. A high-performing olivine material of the type LiMPO4 (M = Fe, Ni, and Co) [3] has been modified by inserting into the structure high-valence transition metal ions (e.g., V(V), Nb(IV), and Ta(IV)) [4]. The effects of the insertion of the different ions on the structural, morphological, electrical and electrochemical properties of the materials have been thoroughly studied. The stoichiometry is evaluated by means of Inductively-Coupled Plasma Atomic Emission Spectroscopy (ICP-AES); the morphology and size distribution of the grains are characterized by Scanning Electron Microscopy (SEM) and High-Resolution Transmission Electron Microscopy (HR-TEM); the structure is examined by powder X-Ray Diffraction (XRD) as well as a variety of IR spectroscopy techniques. The electrochemical characterization is carried out by Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS), and charge/discharge tests at different current rates. Finally, the conductivity mechanism is studied by Broadband Electrical Spectroscopy (BES). The cathode materials described in this report exhibit a high performance in terms of working potential (4.0 ÷ 5.0 V vs. Li/Li+), specific capacity (149 mAh∙g-1), and specific energy (656 mWh∙g-1). Moreover, the insertion of high-valence transition metals results in an improvement of the rate capability of the cathodes, allowing for fast charge and discharge processes.

References

[1] V. Di Noto, T. A. Zawodzinski, A. M. Herring, G. A. Giffin, E. Negro, S. Lavina, Int. J. Hydrogen Energy 37 (2012) 6120-6131.
[2] B. Scrosati, J. Garche, J. Power Sources 195 (2010) 2419-2430.
[3] G. Pagot, F. Bertasi, G. Nawn, E. Negro, G. Carraro, D. Barreca, C. Maccato, S. Polizzi, V. Di Noto, Adv. Funct. Mater. 25 (2015) 4032-4037.
[4] G. Pagot, M. Bandiera, K. Vezzù, A. Migliori, R. Bertoncello, E. Negro, V. Morandi, V. Di Noto, Journal of Materials Chemistry A, doi: 10.1039/D0TA06865A
Photo-Induced Signal Chains at Enzyme Electrodes
Authors: Riedel Marc , Lisdat Fred 
Published: July 2021

During the last decade photoelectrochemical devices which couple biochemical reactions to light-sensitive electrodes have gained increasing research interest. These kind of light-triggered systems have the inherent advantage that an additional tool - the light - can be used to control the reactions at a sensing electrode. This allows a light-directed read-out, but can also be used to change the energetic situation on the surface resulting in advantageous potential behavior [1].
Enzymes as biocatalysts provide the advantage of a catalytic analyte conversion and specificity in this reaction. In order to couple them to light-sensitive electrodes different approaches have used.
Besides the use of co-substrates or products [2], we have been focusing on the use of mediators for this interaction [3] or the establishment of a direct electron transfer of the enzyme to the light- sensitive entity [4]. Here we report on the use of two different types of polymers for establishing the electrical contact.
In order to exploit the advantages of a high surface area we have constructed 3D electrodes which can be rather easily prepared by a template approach combined with spin coating as deposition method..Thus, the thickness of the electrode structure can be adjusted in a defined way [5,6].
In a first approach 3D TiO2 of inverse opal character has been sensitized by a conducting polymer – sulfonated polyaniline. The polymer has here two functions: It ensures the light sensitivity in the visible range and also provides an interface at which the enzyme can exchange electrons. Advantageously the current signal can be gained at rather low potential. Furthermore, the response can be tuned by the dimensions of the 3D electrode demonstrating the scalability of the approach.
As a further advancement we have used a redox polymer in order to couple FAD-dependent glucose dehydrogenase to the electrode. Here PbS QDs have been generated directly onto a 3D TiO2 electrode and characterized by TEM and photoelectrochemistry. The system allows the generation of a defined anodic photocurrent, which can be significantly enhanced by the biocatalytic conversion of glucose. Here the substrate dependent current signal starts at about -054V vs Ag/AgCl.
Such electrode systems can find application in light-triggered sensing, but also for bioenergetics since the photocatalytic process can be “feeded” by electrons from the biocatalytic conversion.
References
[1] F. Lisdat, D. Schäfer, A. Kapp, Anal. Bioanal. Chem. 405, 3739 (2013).
[2] J. Tanne, D. Schäfer, W. Khalid, W. J. Parak, F. Lisdat, Analytical Chemistry 83 (20) (2011) 7778–7785
[3] M. Riedel, N. Sabir, F. W. Scheller, W. J. Parak, F. Lisdat, Nanoscale 9, 2814 (2017).
[4] Ch. Stoll, S. Kudera, W.J. Parak, F. Lisdat,”,SMALL 2 (6) (2006) 741-743).
[5] M. Riedel, F. Lisdat, ACS Applied Materials & Interfaces, (2018), Vol. 10 (1), p. 267-277
[6] M. Riedel, W. Parak, A. Ruff, W. Schuhmann, F. Lisdat, ACS Catalysis, (2018), Vol. 8, 5212-5220