Effect of Electrode/Electrolyte Coupling on Birnessite (δ-MnO) Mechanical Response and Degradation.

Understanding the deformation of energy storage electrodes at a local scale and its correlation to electrochemical performance is crucial for designing effective electrode architectures. In this work, the effect of electrolyte cation and electrode morphology on birnessite (δ-MnO) deformation during charge storage in aqueous electrolytes was investigated using a mechanical cyclic voltammetry approach via atomic force microscopy (AFM) and molecular dynamics (MD) simulation. In both KSO and LiSO electrolytes, the δ-MnO host electrode underwent expansion during cation intercalation, but with different potential dependencies.

Importance of Nuclear Quantum Effects on Aqueous Electrolyte Transport under Confinement in TiC MXenes.

Protons display a high chemical activity and strongly affect the charge storage capability in confined interlayer spaces of two-dimensional (2D) materials. As such, an accurate representation of proton dynamics under confinement is important for understanding and predicting charge storage dynamics in these materials. While often ignored in atomistic-scale simulations, nuclear quantum effects (NQEs), e.

Effects of interlayer confinement and hydration on capacitive charge storage in birnessite.

Nanostructured birnessite exhibits high specific capacitance and nearly ideal capacitive behaviour in aqueous electrolytes, rendering it an important electrode material for low-cost, high-power energy storage devices. The mechanism of electrochemical capacitance in birnessite has been described as both Faradaic (involving redox) and non-Faradaic (involving only electrostatic interactions). To clarify the capacitive mechanism, we characterized birnessite's response to applied potential using ex situ X-ray diffraction, electrochemical quartz crystal microbalance, in situ Raman spectroscopy and operando atomic force microscope dilatometry to provide a holistic understanding of its structural, gravimetric and mechanical responses.

Atomistic-scale insight into the polyethylene electrical breakdown: An eReaxFF molecular dynamics study.

Cross-linked polyethylene (XLPE) has been recognized as an outstanding insulator for high-voltage power cables due to its favorable structural integrity at high temperature, low moisture sensitivity, chemical resistance, and low rates of failure due to aging. However, the roles of by-products and amorphous regions generated during the XLPE production are not clearly known at the atomistic scale. In this study, we present an eReaxFF-based molecular dynamics simulation framework with an explicit electron description verified against density functional theory data to investigate the roles of XLPE by-products and processing variables such as density and voids on the time to dielectric breakdown (TDDB) of polyethylene (PE).

Wafer-Scale Lateral Self-Assembly of Mosaic TiCT MXene Monolayer Films.

Bottom-up assembly of two-dimensional (2D) materials into macroscale morphologies with emergent properties requires control of the material surroundings, so that energetically favorable conditions direct the assembly process. MXenes, a class of recently developed 2D materials, have found new applications in areas such as electrochemical energy storage, nanoscale electronics, sensors, and biosensors. In this paper, we present a lateral self-assembly method for wafer-scale deposition of a mosaic-type 2D MXene flake monolayer that spontaneously orders at the interface between two immiscible solvents.

Structure and Dynamics of Aqueous Electrolytes Confined in 2D-TiO/TiCT MXene Heterostructures.

The synthesis of heterostructures of different two-dimensional (2D) materials offers an approach to combine advantages of different materials constituting the heterostructure and ultimately enhance their performance for applications such as electrochemical energy storage, achieving high energy, and high-power densities. Understanding the behavior of ions and solvents in confinement between these dissimilar layers is critical to understand their performance and control. Considering aqueous electrolytes, we explore the heterostructure of 2D lepidocrocite-type TiO (2D-TiO) and hydroxylated or O-terminated TiC MXene using ReaxFF molecular dynamics simulations and elastic/quasielastic neutron scattering techniques.

Evaluation of postoperative analgesic efficacy and perioperative hemodynamic changes with low dose intravenous dexmedetomidine infusion in patients undergoing laparoscopic cholecystectomy - A randomised, double-blinded, placebo-controlled trial.

Background And Aim: Dexmedetomidine is a α2-agonist with sedative, sympatholytic and analgesic properties and hence, it can be a very useful adjuvant in anesthesia as stress response buster, sedative and analgesic. We aimed to evaluate the effects of low dose dexmedetomidine infusion (0.5 mcg/kg/h) on postoperative analgesic efficacy along with the perioperative hemodynamic changes in patients undergoing laparoscopic cholecystectomy.