42 research outputs found
New Mn Electrochemistry for Rechargeable Aqueous Batteries: Promising Directions Based on Preliminary Results
No full textAqueous batteries with metal anodes exhibit robust anodic capacities, but their energy densities are low because of the limited potential stabilities of aqueous electrolyte solutions. Current metal options, such as Zn and Al, pose a dilemma: Zn lacks a sufficiently low redox potential, whereas Al tends to be strongly oxidized in aqueous environments. Our investigation introduces a novel rechargeable aqueous battery system based on Mn as the anode. We examine the effects of anions, electrolyte concentration, and diverse cathode chemistries. Notably, the ClO4-based electrolyte solution exhibits improved deposition and dissolution efficiencies. Although stainless steel (SS 316 L) and Ni are stable current collectors for cathodes, they display limitations as anodes. However, using Ti as the anode resulted in increased Mn deposition and dissolution efficiencies. Moreover, we evaluate this system using various cathode materials, including Mn-intercalation-based inorganic (Ag0.33V2O5) and organic (perylenetetracarboxylic dianhydride) cathodes and an anion-intercalation-chemistry (coronene)-based cathode. These configurations yield markedly higher output potentials compared to those of Zn metal batteries, highlighting the potential for an augmented energy density when using an Mn anode. This study outlines a systematic approach for use in optimizing metal anodes in Mn metal batteries, unlocking novel prospects for Mn-based batteries with diverse cathode chemistries. © 2024 The Author(s). Energy & Environmental Materials published by John Wiley & Sons Australia, Ltd on behalf of Zhengzhou University.TRUEsciescopu
Laser exfoliated 2D MXene for supercapacitor applications
No full textMXenes-based compounds, particularly Ti3C2Tx, have been studied intensively as electrodes for supercapacitors due to their layered structure and high conductivity, enabling facile ion diffusion and charge transfer. However, tight restacking of the 2D layers in these materials limits their practical, accessible surface area, thereby impeding their capacity and rate capability performance. To mitigate this phenomenon, we present a new approach using a processing method based on laser beam irradiation to modify Ti3C2Tx films. We found that the laser treatment induces chemical and morphological changes, ultimately optimizing the stacking arrangement of the MXene electrodes and consequently enhancing their capacity in both neutral and acidic electrolytes. Furthermore, the laser-modified MXene electrodes demonstrate excellent rate capabilities, showing 84 % retention at extreme rates of 0.5 V compared to only 33 % of the original Ti3C2Tx electrodes. Finally, we discuss the chemical and physical changes induced by the laser treatments and their influence on the electrochemical behavior of the lasered MXene. The principles of laser exfoliation discovered in this study can be implemented in broader 2D materials for various applications
In Situ Porous Structure Characterization of Electrodes for Energy Storage and Conversion by EQCM-D: a Review
No full textπ-Electron-Assisted Charge Storage in Fused-Ring Aromatic Carbonyl Electrodes for Aqueous Manganese-Ion Batteries
No full textRechargeable manganese batteries hold promise for large-scale energy storage due to the abundance and eco-friendly nature of manganese. A key challenge is developing cathode materials capable of reversibly inserting Mn ions with a high specific capacity. Here, we demonstrate that perylene-3,4,9,10-tetracarboxylic dianhydride electrodes efficiently and reversibly insert Mn2+ ions in 3 M MnCl2 aqueous electrolyte solutions. Leveraging the carbonyl groups and the π-electron configuration, such compounds can serve as robust redox centers, facilitating reversible interactions with divalent ions such as Mn2+. Through comprehensive studies involving electrochemistry, elemental analyses, spectroscopy, and structural analysis, we explored these systems and found them as promising anode materials for Mn batteries. Demonstrating excellent Mn storage capabilities, such molecules could attain a reversible capacity of approximately >185 mAh g-1 at a current density of 100 mA g-1, maintaining an average voltage of approximately 0.8 V vs Mn/Mn2+, while exhibiting notable capacity retention. © 2024 American Chemical Society.FALSEsciescopu
In Situ Real-Time Mechanical and Morphological Characterization of Electrodes for Electrochemical Energy Storage and Conversion by Electrochemical Quartz Crystal Microbalance with Dissipation Monitoring
No full textIn situ real-time gravimetric and viscoelastic probing of surface films formation on lithium batteries electrodes
No full textAbstractIt is generally accepted that solid–electrolyte interphase formed on the surface of lithium-battery electrodes play a key role in controlling their cycling performance. Although a large variety of surface-sensitive spectroscopies and microscopies were used for their characterization, the focus was on surface species nature rather than on the mechanical properties of the surface films. Here we report a highly sensitive method of gravimetric and viscoelastic probing of the formation of surface films on composite Li4Ti5O12 electrode coupled with lithium ions intercalation into this electrode. Electrochemical quartz-crystal microbalance with dissipation monitoring measurements were performed with LiTFSI, LiPF6, and LiPF6 + 2% vinylene carbonate solutions from which structural parameters of the surface films were returned by fitting to a multilayer viscoelastic model. Only a few fast cycles are required to qualify surface films on Li4Ti5O12 anode improving in the sequence LiPF6 < LiPF6 + 2% vinylene carbonate << LiTFSI.</jats:p
Direct Assessment of Nanoconfined Water in 2D Ti<sub>3</sub>C<sub>2</sub> Electrode Interspaces by a Surface Acoustic Technique
No full textAlthough significant progress has
been achieved in understanding
of ion-exchange mechanisms in the new family of 2D transition metal
carbides and nitrides known as MXenes, direct gravimetric assessment
of water insertion into the MXene interlayer spaces and mesopores
has not been reported so far. Concurrently, the latest research on
MXene and Birnessite electrodes shows that nanoconfined water dramatically
improves their gravimetric capacity and rate capability. Hence, quantification
of the amount of confined water in solvated electrodes is becoming
an important goal of energy-related research. Using the recently developed
and highly sensitive method of in situ hydrodynamic spectroscopy (based
on surface-acoustic probing of solvated interfaces), we provide clear
evidence that typical cosmotropic cations (Li+, Mg2+, and Al3+) are inserted into the MXene interspaces
in their partially hydrated form, in contrast to the insertion of
chaotropic cations (Cs+ and TEA+), which effectively
dehydrate the MXene. These new findings provide important information
about the charge-storage mechanisms in layered materials by direct
quantification and efficient control (management) over the amount
of confined fluid in a variety of solvated battery/supercapacitor
electrodes. We believe that the proposed monitoring of water content
as a function of the nature of ions can be equally applied to solvated
biointerfaces, such as the ion channels of membrane proteins
In Situ Multilength-Scale Tracking of Dimensional and Viscoelastic Changes in Composite Battery Electrodes
No full textElectrochemical Quartz Crystal Microbalance with Dissipation Real-Time Hydrodynamic Spectroscopy of Porous Solids in Contact with Liquids
No full textUsing multiharmonic
electrochemical quartz crystal microbalance
with dissipation (EQCM-D) monitoring, a new method of characterization
of porous solids in contact with liquids has been developed. The dynamic
gravimetric information on the growing, dissolving, or stationary
stored solid deposits is supplemented by their precise in-operando
porous structure characterization on a mesoscopic scale. We present
a very powerful method of quartz-crystal admittance modeling of hydrodynamic
solid–liquid interactions in order to extract the porous structure
parameters of solids during their formation in real time, using different
deposition modes. The unique hydrodynamic spectroscopic characterization
of electrolytic and rf-sputtered solid Cu coatings that we use for
our “proof of concept” provides a new strategy for probing
various electrochemically active thin and thick solid deposits, thereby
offering inexpensive, noninvasive, and highly efficient quantitative
control over their properties. A broad spectrum of applications of
our method is proposed, from various metal electroplating and finishing
technologies to deeper insight into dynamic build-up and subsequent
development of solid-electrolyte interfaces in the operation of Li-battery
electrodes, as well as monitoring hydrodynamic consequences of metal
corrosion, and growth of biomass coatings (biofouling) on different
solid surfaces in seawater
