bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electro-Conversion of Lignin to Highly Value-Added Products
Authors: Waldvogel Siegfried R 
Published: July 2022

After cellulose and hemicellulose, lignin represent the most abundant part of the plant biomass. Due to the large waste stream originating from pulping processes, only Kraft lignin and lignosulfonates are of technical interest. Using electric current as sustainable reagent for degradation avoids transition metal catalysts and makes this approach very attractive. However, the natural complexity and stability of lignin make the depolymerization to useful organic building blocks a highly challenging task. The state of the art in the selective anodic degradation of Kraft lignin and other lignins will be reported. This contribution exclusively deals with the direct electrolysis and ex-cell approaches. The major focus will be given on the generation and cost efficient isolation of vanillin and related building blocks.

References:
[1] M. Zirbes, S. R. Waldvogel, Curr. Opin. Green Sustainable Chem.
2018, 14, 19–25.
[2] M. Zirbes, D. Schmitt, N. Beiser, D. Pitton, T. Hoffmann, S. R. Waldvogel, ChemElectroChem
2018, 6, 155–161.
[3] M. Zirbes, L. L. Quadri, M. Breiner, A. Stenglein, A. Bomm, W. Schade, S. R. Waldvogel, ACS Sustainable Chem. Eng.
2020
, 8, 7300–7307.
[4] M. Breiner, M. Zirbes, S. R. Waldvogel, Green Chem.
2021, 23, 6449–6455.

Figure 1
Photosynthetic Reaction Centres Assembled on a Gold Electrode and the Photocurrent - Potential Response
Authors: Jun Daniel , Grzedowski Adrian , Beatty J. Thomas , Bizzotto Dan 
Published: July 2022

The photosynthetic reaction centre (RC) from Rhodobacter sphaeroides has been studied for use in biohybrid solar cells. Much of the previous work has focussed on improving photocurrent generation by loading the electrode surface with many copies of the protein resulting in multilayers. The primary disadvantage with this approach is the random orientation of proteins, with some supposedly oriented properly. We used RCs with Cys for covalent attachment to a gold electrode and for proper orientation. Areas of bare electrode surface and RCs bound non-specifically (i.e. not bound via the Cys) were competitively displaced by an insulating, non-redox layer of mercaptohexanol (MCH). The adsorbed monolayer of RCs was imaged using atomic force microscopy to detail the distribution of RCs on the gold surface for surfaces prepared with different RC deposition concentrations. Photocurrents were measured for all RC modified surfaces using a LED modulation method which enabled measurement of photocurrent in the presence of large faradaic currents from the sacrificial reactant (hydroquinone) at a variety of applied potentials.[1] The photocurrents generated from a monolayer composed of RCs and MCH resulted in consistent photocurrent currents. which enabled modeling of the photocurrent generation using the Marcus-Hush-Chidsey theory to extract a reorganization energy for this process. Multilayers of adsorbed RCs were distinctly different and revealed that the local environment in which the RCs are embedded significantly influenced photocurrent generation.
[1] Jun, D.; Beatty, J. T.; Bizzotto, D. Highly Sensitive Method to Isolate Photocurrent Signals From Large Background Redox Currents on Protein‐Modified Electrodes. ChemElectroChem
2019, 6 (11), 2870–2875.
Transport Phenomena in Ion-Exchange Membranes
Authors: Solberg Simon Birger Byremo , Burheim Odne Stokke 
Published: July 2022

Ion-exchange membranes (IEM) are an essential component of electrochemical systems such as reverse electrodialysis (RED) and flow batteries. For RED, the membranes separate alternating concentrate and dilute solutions, creating emf. Stacks of such repeating units in series can be used as flow batteries [1] or to produce hydrogen [2] given appropriate electrode selection. Using non-equilibrium thermodynamics, the coupled solute and solvent transport through IEM may be understood in terms of transport numbers [1]. This work highlights the coupling between salt and water fluxes through membranes in RED, and the implications for the efficiency of various technologies which rely upon IEM in contact with aqueous solutions. In general for a mixture of one solute and solvent, the water transported together with ions across the IEM decreases the permselectivity, and thus the emf, of the membrane.
[1] D. Bedeaux, S. Kjelstrup, Non-Equilibrium Thermodynamics of Heterogeneous Systems, World Scientific, 2008.
[2] K. W. Krakhella, M. Morales, R. Bock, F. Seland, O. S. Burheim, K. E. Einarsrud, Electrodialytic Energy Storage: Permselectivity Stack Measurements and Life-Cycle Analysis, Energies 13, 2020.
Cyano-Anion Intercalated Layered Double Hydroxides for Electrocatalytic Degradation of Acetaldehyde in Gas Phase
Authors: Muthuraman Govindan , Choi Youngyu , Daekeun Kim 
Published: July 2022

Layered double hydroxides (LDHs) are identified as potential material in water splitting or oxygen evolution reaction (OER). Since the water splitting potential is minimized when the use of LDH modified electrode, the application of the LDHs has been still challenged in air pollution control but the water splitting potential should be attempted to extended. Anions or cations intercalation has many applications in electrocatalysis and energy harvesting field. In this approach, the present work aimed to investigate a cyano-anion intercalation on NiCo-LDH and its application to degradation of acetaldehyde in gas phase.
The NiCo-LDH was prepared using coprecipitation method under a low temperature. The prepared NiCo-LDH was intercalated with cyano-anion using KCN. After surface characterization to confirm the intercalation of cyano-anion, the NiCo-CN-LDH was coated on a 3D metal foam electrode using a 5% Nafion solution. Redox behavior of the prepared NiCo-CN-LDH electrode was observed in 1M KOH solution by cyclic voltammetry (CV) technique. Once identified the water splitting potential window, the NiCo-CN-LDH electrode was examined on the acetaldehyde (AA) reduction/oxidation in the 1M KOH solution. To evaluate the NiCo-CN-LDH electrode effect on AA, the potential truncated CV at various potential regions. After solution-phase CV analysis, the NiCo-CN-LDH electrode was fitted into Nafion membrane divided electrolytic flow through cell for the gas-phase degradation analysis either by anodic or cathodic half-cell. The NiCo-CN-LDH electrode’s redox behavior was analyzed and compared with solution phase redox behavior. Then the NiCo-CN-LDH electrode was applied on the AA degradation either by oxidation or reduction by continuous flow of AA gas. The degradation efficiency was monitored by ex-situ GC-MS. The promoted effect of cyano-anion on widening the water splitting potential window and its usage on gas phase AA degradation will be discussed in detail at the conference.
Acknowledgement: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (Grant No.: NRF-2021R1I1A1A01049901) and from the Grant No. NRF-2020R1A6A1A03042742.
Characterizing Recast Nafion® Film Electrode Interface Diffusion and Kinetics in a Non-Aqueous System
Authors: Lehto Danielle , Claire Anna , Zacher Peter , Knoche Gupta Krysti 
Published: July 2022

The effect of recast Nafion® films on platinum working electrodes in acetonitrile will be characterized by cyclic voltammetry and rotating disk voltammetry. Until now, the behavior of recast Nafion® in a non-aqueous system has not been reported in this way. The behavior of recast Nafion® films in acetonitrile has been anecdotally observed to be different from the behavior in aqueous solutions, which have also been comprehensively studied1,2. The reversible redox couple of Tris(2,2′-bipyridine)ruthenium(II) hexafluorophosphate, Ru(bpy)3
2
++, in an acetonitrile electrolyte solution will be compared between a bare platinum working electrode and a recast Nafion® film coated platinum working electrode by cyclic voltammetry. In cyclic voltammetry the convective mass transport of the species is limited only to the diffusion at the stationary electrode interface. In rotating the working electrode (RDE) the limitation on mass transport is extended beyond the stationary diffusion behavior. The current is dependent on and limited by the mass transport of the species to the electrode interface where it can undergo redox, the limiting current of both a bare platinum working electrode system and of a recast Nafion® film coated platinum working electrode will be observed by changing the rotation rate of the RDE. The diffusion interface of the electrode inside an acetonitrile solution of Ru(bpy)3
2
+ and an electrolyte will be determined by rotating disk voltammetry at a bare platinum working electrode and at a recast Nafion® film coated platinum working electrode. The film solution interface thickness will be reported along with the effect on the diffusion of the interface between bare and recast Nafion® coated platinum working electrodes.
1. S. K. Zecevic et al 1997 J. Electrochem. Soc.
144 2973
2. T. A. Zowodzinski, S. Gottesfeld et al 1997 Advances in Electrochemical Sciences and Engineering
Sustained Release of AgNO3 Additive in Carbonate Electrolytes for Stable Lithium Metal Anodes
Authors: Kang Hyeonmuk , Kim Taehee , Hwang GyuSeong , Shin GeunHyeong , Lee Junho , Cho EunAe 
Published: July 2022

With increasing energy storage demand, research on high energy density and stable battery became essential. Among different anode materials for lithium batteries, lithium metal is an ideal anode material as it has low redox potential and high specific capacity. Therefore, for post-lithium ion battery with high energy density cannot avoid using lithium metal as an anode. However, lithium metal anode has stability and safety issues due to dendritic growth. Lithium metal in contact with organic electrolyte reacts with the electrolyte to form solid electrolyte interface (SEI). SEI prevents further electrolyte consumption, however presence of unstable SEI causes uneven lithium ion diffusion through the SEI layer and induces lithium dendrite growth. Therefore, uniform deposition of lithium and stable SEI is important to operate lithium metal anode safely.
The application of nitrate additives in carbonate electrolyte has been very limited due to poor solubility. However, nitrate containing polymer interlayer can release additive constantly enabling nitrate act as an electrolyte additive. Herein, AgNO3 synthesized with PAN nanofibers (AgPAN) is used as an additive to induce uniform lithium deposition and stable SEI formation. In the symmetric cell test, life time of 20 µm thick lithium foil enhanced from 140 hr to 300 hr with AgPAN. Lithium nucleation overpotential disappeared and overall overpotential is reduced. Originally, plane lithium foil had the sparsely deposited dendrite shaped lithium, but with AgPAN lithium was evenly deposited and grow in spherical shape. Ag+ reduces on lithium metal surface acting as a lithium nucleation seed helping uniform lithium deposition and NO3
- reacts with lithium to form stable inorganic SEI layer (Li2O, Li3N, LiNxOy, and etc) resulting in stable cycling of lithium metal anode.
Analysis of Deterioration Mechanism of Al-Pouch Film Used As Packaging Materials for Lithium Ion Batteries
Authors: Park Bo Keun , Kim Yong Min , Kim Ki Jae 
Published: July 2022

Generally, lithium ion batteries (LIBs) can be divided into three different types: cylindrical, prismatic, and pouch-type LiBs with regard to the packaging form. Contrary to cylindrical or prismatic type batteries, pouch-type battery uses a pouch as an exterior material to protect inside of the cell from external influences, and have a metal lead-taps to receive and deliver electricity from external source. To safeguard the inside of the lithium ion battery, the pouch must have high resistance to gas and moisture permeability and excellent corrosion resistance to electrolytes.
However, Al-pouch can be prone to contamination from electrolyte containing lithium salt during the electrolyte injection process, a key part of their manufacturing process. This electrolyte contamination can be fatal to the long-term reliability or durability of pouch-type LiBs. In this study, we investigate deterioration behavior of aluminium pouch film due to the electrolyte contamination. In order to clarify deterioration mechanism of Al-pouch film, we prepared exposure test of Al-pouch film and dummy cell samples which were stained by electrolyte droplet (LiPF6 in EC:EMC=1:2 (v/v) + 2 % VC). The change of micro-structure of the samples was tracked during 20 weeks by storing them under accelerated test conditions (RH 95 %, 60 ℃). As a result, we find out severe defect of the samples of Al-pouch film by damage to outermost nylon film and aluminium layer, and confirmed the effects on the battery after the defects occurred.
To understand such phenomena, the micro-defect of Al-pouch films was observed by characterization techniques (XRD, FT-IR, SEM, EDX). We demonstrate that outermost layer of nylon film is damaged when it reacts with an electrolyte containing LiPF6 salt such as decreasing crystallinity, surface crazing, forming microdefects. The degradation of nylon film leads to severe surface cracking, followed by nylon locally peeling off from the Al-pouch. Peeling of the nylon film causes to expose the underlying thin aluminum film that constitute the middle layer of Al-pouch. Once partially exposed to the atmosphere, severe pitting corrosion of the aluminum film occurs due to atmospheric moisture and acids produced by LiPF6. Finally, a large amount of moisture to easily penetrate pouch-type LiBs through these corroded pits, showing the detrimental effects of electrolyte contamination on pouch-type LiBs’ long-term durability and reliability.

Figure 1
Understanding the Role of Liquid Electrolytes in Performance Improvement of Solid-State Lithium Metal Batteries
Authors: Yan Shuo , Merati Ali , Yim Chae-Ho , Baranova Elena , Weck Arnaud , Abu-Lebdeh Yaser 
Published: July 2022

Abstract

Garnet-type Li7La3Zr2O12 (LLZO) Solid-State Electrolytes (SSEs) enable Solid-State Lithium Metal Batteries (SSLMBs) with high power density due to their superior ionic conductivity over 1 mS cm-1 at room temperature and good chemical stability against Lithium (Li) metal. A major cause of failure in SSLMBs is the large interfacial resistance between LLZO and electrodes. The high resistance at the interfaces is normally associated with insufficient solid-solid surface contact. It is a common practice to introduce a Liquid Electrolyte (LE) in SSLMBs either in combination with SSEs to form quasi-solid electrolytes or as the interface to enhance battery cycling performance. Several studies are conducted on resolving the contact issue between LLZO and the Li-metal anode but very few focused on the LLZO/cathode interface.
In this research, a carbonate-based LE was introduced at the interface of Li6.5La2.9Ba0.1Zr1.4Ta0.6O12 (LLBZTO) | LiNi0.6Mn0.6Co0.2O2 (NMC 622) cathode with the aim of understanding the mechanism which the LE enhances the SSLMBs performance, using the Scanning Transmission X-ray Microscopy (STXM) and X-ray Absorption Scanning (XAS). The assembled Li | LLBZTO SSEs | LE | NMC 622 cell exhibited an initial discharge capacity of 168 mAh g-1 with a capacity retention ratio of ~82 % after 30 cycles. The results from the STXM revealed the reactions of the LE with LLZO and NMC 622. The XAS analysis showed the formation of two new interfaces: Cathode-Electrolyte Interface (CEI) and Solid-Liquid Electrolyte Interface (SLEI). Also, the result indicated that the LE decomposed completely in the cell after 30 cycles and transformed to a dense and robust SLEI. This in turn led to the enhanced interfacial contact with the cathode and an improved Li+ ion transport at the interface. In addition, fluorides (i.e., LiF and LaF3) and carbonates (i.e., Li2CO3) were confirmed as the main components of the SLEI. In this study, two interfaces in SSLMBs (CEI and SLEI) were characterized. Fully understanding the roles of LE as the interface would enhance the practical application of quasi-solid electrolytes in SSLMBs.

Keywords

Solid-state lithium metal batteries; Garnet; Interface; Ceramic electrolyte; STXM
A Theoretical Investigation into pH of Neat Water at the Nanoscopic Scale Via Rexpon Force Field and Stochastic Simulations
Authors: Li Sirui , Kwon Soonho , Yu Ethan , Goddard William , Houle Frances 
Published: July 2022

Design of durable solar CO2 conversion devices requires a mechanistic understanding of molecular-level reactions at the electrode-electrolyte interface that lead to interfacial degradation.[1] This interface often incorporates such features as a porous and rough surface to maximize active area and enhance catalytic performance. However, this roughness may introduce local water pool inclusions, whose size may have an unforeseen, detrimental impact on device durability due to their local pH being very different from the bulk pH. It is well-recognized that for water pools containing less than molecules, the solution pH cannot be defined in the conventional sense because the pools are too small to support stable water ion concentrations near neutral pH. Rather, the water ion concentrations fluctuate to very high values for short periods of time. To better understand pH in small pools, we combine theoretical calculations using QM/MD and stochastic simulations [3]. We combined Ab initio MD and the accurate RexPoN force field [2] simulation to quantify the thermodynamic free energy to create water ion pairs through the reaction as a function of the water pool size. The free energies are used to calculate the equilibrium constants for this reaction and the ion pair generation and recombination rate constants. The rate constants are then used as inputs to the stochastic simulations to gain insights into ion pair generation frequency and lifetime statistics over extended periods of time (hours). Proton and hydroxide diffusion are also incorporated in the stochastic simulation to understand how far water ions may travel from where they are generated. The results show that the combination of Grotthuss and vehicular diffusion mechanisms for H3O+ and OH- can lead to unequal distributions at an adjacent interface. We will discuss how the stochastic generation and recombination of water ions influences buffer chemistry and dissolved CO2 chemistry.
Reference
[1] S. Nitopi, E. Bertheussen, S.B. Scott, X. Liu, A.K. Engstfeld, S. Horch, B. Seger, I.E.L. Stephens, K. Chan, C. Hahn, J.K. Nørskov, T.F. Jaramillo, I. Chorkendorff, Progress and Perspectives of Electrochemical CO2 Reduction on Copper in Aqueous Electrolyte, Chem. Rev. 119 (2019) 7610–7672. https://doi.org/10.1021/acs.chemrev.8b00705.
[2] S. Naserifar, W.A. Goddard, The quantum mechanics-based polarizable force field for water simulations, J. Chem. Phys. 149 (2018). https://doi.org/10.1063/1.5042658.
[3] W.D. Hinsberg, F.A. Houle, Kinetiscope, (n.d.). http://www.hinsberg.net/kinetiscope.
Bipolar Electrochemistry for the Synthesis of Anodic TiO2 Nanotube Layers
Authors: Sopha Hanna , Macak Jan M. 
Published: July 2022

Self-organized TiO2 nanotube (TNT) layers have attracted considerable scientific and technological interest over the past 17 years motivated for their wide range of applications including (photo-) catalysis, hydrogen generation and biomedical uses [1,2]. The synthesis of these TNT layers is carried out by electrochemical anodization of valve Ti metal substrates in various F--containing electrolytes using a conventional 2-electrode set-up with the Ti substrate as anode and a Pt-foil as cathode.
Instead of using a conventional set-up, also bipolar electrochemistry can be employed for the anodization of valve metals [3-7]. In this set-up, the Ti substrate is placed in an electrolyte between two so-called feeder electrodes, which are connected to the potentiostat. Due to the electric field between the feeder electrodes, the Ti substrate is polarized. If the applied potential between the feeder electrodes is high enough, redox reactions can be driven on the Ti substrate. This method opens new doors for the preparation of TNT layers with gradients in dimensions (i.e. diameter and length of the nanotubes) [3-5] as well as for the preparation of TNT layers on Ti substrates, which cannot be directly connected to the potentiostat, e.g. Ti spheres [8].
In this presentation, the preparation of TNT layers on small Ti spheres [8] as well as on 3D printed Ti substrates [9] using bipolar electrochemistry will be shown and discussed. Furthermore, we will also show the possibility of using closed bipolar electrochemical cells, consisting of two closed half-cells with the Ti substrate as obstacle between the cells [10].
References:
[1] J.M. Macak et al., Curr. Opin. Solid State Mater.
2007, 11, 3.
[2] Lee, K. et al., Chem. Rev.
2014, 114, 9385.
[3] G. Loget et al, J. Mater. Chem A
2014, 2, 17740.
[4] G. Loget et al., Langmuir
2014, 30, 15356.
[5] W. Wei et al., Electrochim. Acta
2015, 176, 1393.
[6] H. Asoh et al., RSC Adv.
2016, 6, 90318.
[7] H. Asoh et al., J. Electrochem. Soc.
2018, 165, C295.
[8] H. Sopha et al., Electrochem. Commun.
2020, 111, 106669.
[9] H. Sopha et al., Nano Lett.
2021, 21, 8701.
[10] H. Sopha et al., ChemElectroChem
2021, 8, 3827.
The Role of Viscosity Variations: Analyzing and Modelling Microfluidic Membrane-Free Laminar Flow Batteries
Authors: de las Heras Miguel , Quintero Alberto Emanuel , Ibanez Santiago Enrique , Vera Marcos 
Published: July 2022

Membraneless micro redox flow batteries prevent the advective mixing of catholyte and anolyte by operating at a small Reynolds number with flow rates of order 100µL/min or less [1] [2] [3] [4]. This laminar flow regime allows to remove the ion-exchange membrane used in conventional macro flow batteries. The absence of membrane decreases the internal electric resistance of the reactor, reduces manufacturing costs and potentially increases the performance of the system. However, removing the physical barrier between the electrolytes poses a new challenge: the accurate control of the thin region where both miscible electrolytes enter in contact. Undesired deflections of that mixing region (see Fig. 1) may lead to increased crossover losses and net liquid transfer between the tanks.
In this work we propose a numerical CFD model that sheds light on the behaviour of the mixing region at different flow conditions, considering viscosity changes in the electrolytes resulting from variations in the local state of charge during the operation of the cell. Then, a simplified dynamic model that includes electric current, flow rates and electrolyte properties as input parameters is proposed and validated against the CFD simulations. The present work constitutes the first study of membraneless micro redox flow batteries in non-ideal conditions arising from electrolyte heterogeneities. Our computationally efficient model allows to consider qualitative and long-term trends in a matter of minutes to hours, covering broad operation envelopes, which can be used to guide the design process of these emerging systems.

Figure 1: Undesired deflection of the mixing region

Acknowledgments

This work has been partially funded by the Agencia Estatal de Investigación (PID2019-106740RB-I00/AEI/10.13039/501100011033), and by Grant IND2019/AMB-17273 of the Comunidad de Madrid.

References

[1] Ferrigno et al. “Membraneless Vanadium Redox Fuel Cell Using Laminar Flow”. In: JACS Communications (2002).
[2] Choban et al. “Membraneless Fuel Cell Based on Laminar Flow”. Fuel Cell Science, Engineering and Technology. 2003.
[3] Kjeang et al. “A Microfluidic Fuel Cell with Flow-Through Porous Electrodes”. In: JACS Articles (2008).
[4] William Allan Braff. “Membraneless Hydrogen Bromine Laminar Flow Battery for Large-Scale Energy Storage”. PhD thesis. Massachusetts Institute of Technology, Feb. 2014

Figure 1