This paper focuses on the choice of optimal pore size and effect dispersion, which is important for rational design nanoporous supercapacitors. Optimization carbon electrodes discussed in terms maximal stored energy density. By applying a previously developed theory, supporting it by newly performed experiments, we find that density non-monotonic function monodisperse porous electrodes. The ‘optimal’ provides increases with increasing operating voltage saturates at high voltages. We also...

In recent experiments (Chmiola et al 2006 Science 313 1760; Largeot 2008 J. Am. Chem. Soc. 130 2730) an anomalous increase of the capacitance with a decrease pore size carbon-based porous electric double-layer capacitor has been observed. We explain this effect by image forces which exponentially screen out electrostatic interactions ions in interior pore. Packing same sign becomes easier and is mainly limited steric interactions. call state 'superionic' suggest simple model to describe it....

Recently observed anomalous properties of ionic-liquid-based nanoporous supercapacitors [C. Largot et al., J. Am. Chem. Soc., 2008, 130, 2730-2731] have attracted much attention. Here we present Monte Carlo simulations a model ionic liquid in slit-like metallic nanopores. We show that exponential screening the electrostatic interactions ions inside pore, as well image-charge attraction to pore surface, lead 'anomalous' increase capacitance with decreasing width. The simulation results are...

We discuss the nonlinear effects and efficiency of charge storage in supercapacitors with nanoporous electrodes ionic liquids, demonstrate that to maximize stored energy, it may be beneficial create 'obstacles' or 'difficulties' charging. This can achieved by making thermodynamically unfavourable conditions for ions inside nanopores, more favourable outside. show means Monte Carlo simulations such 'ionophobic' pores store energy efficiently provide equivalent even better capacity. Since...

Nanoporous supercapacitors attract much attention as green energy storage devices with remarkable cyclability and high power densities. However, their use in high-frequency applications is limited by relatively slow charging processes, while accelerating without compromising the still remains a challenging task. Here, we study detail discharging behavior of nanoporous narrow pores, which provide exceptionally capacitances stored We scrutinize dynamic modes charging, revealing, particular,...

Abstract Electrolyte-filled subnanometre pores exhibit exciting physics and play an increasingly important role in science technology. In supercapacitors, for instance, ultranarrow provide excellent capacitive characteristics. However, ions experience difficulties entering leaving such pores, which slows down charging discharging processes. earlier work we showed a simple model that slow voltage sweep charges quicker than abrupt step. A slowly applied avoids ionic clogging co-ion trapping—a...

An improved mean-field model used earlier (J. Phys.: Condens. Matter2011, 23, 022201) to explain the anomalous increase of capacitance in nanoporous supercapacitors is extended study charging dynamics. We find that initially empty (i.e., ionic liquid-phobic) pores proceeds a front-like way, while filled ionophilic) diffusive; both cases, however, accumulated charge grows as square root time. also discuss two-step complementary optimization porous electrodes for supercapacitors. In first...

Charging of a conducting tubular nanopore in nanostructured electrode is treated using an exactly solvable 1D lattice model, including ion correlations screened by ion-image interactions. Analytical expressions are obtained for the accumulated charge and capacitance as function voltage. They show that mechanism storage, qualitative form capacitance-voltage curve, sensitive to how favorable it ions occupy unpolarized pore, pore radius. Qualitative predictions theory corroborated Monte Carlo...

A significant fraction of the cell volume is occupied by various proteins, polysaccharides, nucleic acids, etc., which considerably reduces mobility macromolecules. Theoretical and experimental work so far have mainly focused on dependence volume, while effect a macromolecular shape received less attention. Herein, using fluorescence correlation spectroscopy (FCS) Brownian dynamics (BD) simulations, we report dramatic slowdown tracer diffusion cylindrically shaped double-stranded (ds) DNAs...

Abstract The last decade has seen an exponential expansion of interest in conjugating multiple enzymes cascades close proximity to each other, with the overarching goal being accelerate overall reaction rate. However, some evidence emerged that there is no effect channeling on velocity popular GOx-HRP cascade, particularly presence a competing enzyme (catalase). Herein, we rationalize these experimental results quantitatively. We show that, general, can enhance enzymes, but steady state...

A balanced hierarchical pore ratio enhances the energy storage of biomass-derived activated carbon electrodes while a hybrid electrolyte extends potential window, facilitating fabrication high-energy density next-generation symmetric supercapacitors.

A gap in understanding the link between continuum theories of ion transport ionic liquids and underlying microscopic dynamics has hindered development frameworks for phenomena these concentrated electrolytes. Here, we construct a theory by coarse graining simple exclusion process interacting particles on lattice. The resulting dynamical equations can be written as gradient flow with mobility matrix that vanishes at high densities. This form gives rise to charging behavior is different one...

Large-scale molecular simulations reveal two screening lengths satisfying distinct scaling relations but with unprecedented accuracy no underscreening is detected for concentrated ionic bulk systems.

Abstract The manipulation of microscopic objects requires precise and controllable forces torques. Recent advances have led to the use critical Casimir as a powerful tool, which can be finely tuned through temperature environment chemical properties involved objects. For example, these been used self-organize ensembles particles counteract stiction caused by Casimir-Liftshitz forces. However, until now, potential torques has largely unexplored. Here, we demonstrate that efficiently control...

We present a coarse-grained, continuum kinetic theory for charging supercapacitors with narrow cylindrical nanopores. The reveals that the occupancy of nonpolarized pore and energy barrier ion–ion interdiffusion are key issues controlling different regimes dynamic response. For 'ionophobic' pores, where is empty at no applied voltage, charge density advances into via diffusion-like dynamics. mechanism an 'ionophilic' starkly different: moderate ionophilicities, co-ions expelled from in...

Metabolite or substrate channeling is a direct transfer of metabolites from one enzyme to the next in cascade. Among many potential advantages channeling, acceleration total reaction rate considered as most important and self-evident. However, using simple model, supported by stochastic simulations, we show that it not always case; particularly at long times (i.e. steady state) high concentrations, channeled cannot be faster, can even slower, than original non-channeled cascade reaction. In...

We develop a statistical theory of charging quasi single-file pores with cations and anions different sizes as well solvent molecules or voids. This is done by mapping the onto one-dimensional Blume–Emery–Griffith model variable coupling constants. The results are supported three-dimensional Monte Carlo simulations in which many limitations lifted. explore ways enhancing energy storage depend on competitive adsorption ions into pores, degree ionophilicity voltage regimes accessed. identify...

Colloids immersed in a critical or near-critical binary liquid mixture and close to chemically patterned substrate are subject normal lateral Casimir forces of dominating strength. For single colloid, we calculate these attractive repulsive the corresponding potentials within mean-field theory. Within this approach also discuss quality Derjaguin approximation apply it Monte Carlo simulation data available for system under study. We find that range validity is rather large fails only surface...

We study diffusion of macromolecules in a crowded cytoplasm-like environment, focusing on its dependence composition and crossover to the anomalous subdiffusion. The itself depend both volume fraction relative concentration macromolecules. In accordance with previous theoretical experimental studies, slows down when increases. Contrary expectations, however, is also strongly dependent molecular composition. time decreases smaller start dominate. Interestingly, faster (more polydisperse)...

Nanoporous supercapacitors play an important role in modern energy storage systems, and their modeling is essential to predict optimize the charging behaviour. Two classes of models have been developed that consist finite infinitely long pores. Here, we show although both types qualitatively consistent results, there are differences emerging due pore length. In particular, find ion density inside a not constant but increases linearly from entrance end, where ions form strongly layered...

Nanoporous supercapacitors play a key role in energy storage and thereby attract growing interest from the research community. Development of porous electrodes for is paramount importance, but their characterization still remains challenge. Herein, we analyze two examples popular carbide-derived activated carbon point view interpore connectivity ion permeation. Due to limited percolation, effective porosity, as seen by an ion, decreases with increase size, which can reduce stored density...

Recent experiments have shown that the repulsive force between atomically flat, like-charged surfaces confining room-temperature ionic liquids or concentrated electrolytes exhibits an anomalously large decay length. In our previous publication [J. Zeman, S. Kondrat, and C. Holm, Chem. Commun. 56, 15635 (2020)], we showed by means of extremely large-scale molecular dynamics simulations this so-called underscreening effect might not be a feature bulk electrolytes. Herein, corroborate these...