Opposite Charge Research Articles

Pyrrolic-N/C = O cooperative assisted in hollow porous carbon with ultra-high electrochemical performance for Zn-ion hybrid supercapacitors

The development of high-energy–density advanced Zinc-ion hybrid supercapacitors (ZIHSs) shows significant potential, yet it remains a complex undertaking due to its heavy reliance on physical Zn2+ adsorption and the limitations imposed by insufficient cathodes. This study employs a rich in C = O and pyrrolic-N functional groups hollow porous carbon derived from cattail leaves as a cathode material for high-energy-power ZIHSs. The proposed charge storage mechanism involves the assimilation of opposite charge carriers, coupled with a multi-electron redox response, which was investigated by Ex-situ experiments and density functional theory (DFT) simulations. This process entails the alternating binding of Zn2+ and SO42− at designated active sites, along with strong relationships between Zn2+ and electronegative C = O/pyrrolic-N motifs, leading to the creation of C-O-Zn-N-C bonds. Consequently, the aqueous ZIHSs constructed with this hollow porous carbon cathode exhibit outstanding performance metrics. These include an impressive energy density of 128 Wh kg−1, a discharge specific capacity of 149 mAh/g at 10 A/g, a superb power density of 1188 W kg−1, and an extraordinary long-term lifespan, retaining 95 % of its initial capacity after 10,000 cycles. Importantly, the strategy of augmenting energy storage through chemical adsorption capability modulation can be applied to other carbon materials.

Generation of neutral droplets via waveform optimization for stable electrohydrodynamic drop-on-demand printing

Electrohydrodynamic (EHD) drop-on-demand (DOD) printing is a highly promising additive manufacturing technology, particularly for micro- and nanoscale applications, owing to its exceptional printing resolution. However, a significant challenge for EHD DOD to achieve stable printing is the accumulation of residual charge, particularly on highly insulated substrates where the charge cannot be discharged. A novel voltage-driven waveform is proposed to generate neutral droplets in EHD DOD printing, aiming to completely solve the problem of residual charge accumulation. The proposed voltage-driven waveform consists of two waveforms with opposite polarity and equal amplitude. The waveforms of opposite polarity generate two droplets with opposite charges. Overlapping these two droplets causes the charges to be neutralized, therefore generating neutral droplets. The correctness of the proposed method is verified through simulations and experiments, and the printing parameters were optimized accordingly. Notably, silver nanowires with a line width of 5.3 μm were successfully printed on insulating substrates using this technique, and large-area on-demand patterns were stably printed. This outcome underscores the capability of the proposed high-voltage driving waveform to generate charge-neutral droplets, thereby significantly enhancing the stability of EHD DOD printing and facilitating its implementation in high-resolution manufacturing processes.

Energy-Scaled Debye-Hückel Theory for the Electrostatic Solvation Free Energy in Size-Asymmetric Electrolyte Solutions.

In this report, an energy-scaled Debye-Hückel theory is developed for fast and accurate evaluation of the electrostatic solvation free energy in size-asymmetric electrolyte solutions. A size-asymmetric electrolyte solution is mapped to a dielectric continuum medium with Debye-Hückel-like response. Based on the scaling relation of the electrostatic energy of a spherical ion in the small and large size limits, a Padé polynomial is used to interpolate the electrostatic energy at finite size. The Padé polynomial is further interpreted as the electrostatic energy of an effective Debye-Hückel mean field model, depicted by a modified Debye parameter and a surface charge density due to the size asymmetry of the solvent ions. This theory can distinguish the electrostatic energies and the electrostatic solvation free energies of solutes with the same size but opposite charges. Application to charged hard and charged soft spheres demonstrates the accuracy of our approach.

Excess heat production of the pair annihilation of ionic vacancies in a copper redox reaction using a double bipolar MHD electrode.

Through a copper double bipolar magnetohydrodynamic (MHD) electrode (MHDE) producing twice the amounts of ionic vacancies than a conventional single MHDE, the molar excess heat of the pair annihilation of ionic vacancies, 702kJmol-1 at 10T on average was obtained in a copper redox reaction. It was about twice as large as that of a single MHDE, 387kJmol-1 at the same magnetic field. This result strongly suggests that a multi-channel bipolar MHDE will produce much greater excess heat. To conserve the linear momentum and electric charge during electron transfer in an electrode reaction, ionic vacancies are created, storing the solvation energy in the polarized core of the order of 0.1nm, and the pair annihilation of the vacancies with opposite charges liberates the energy as excess heat. The promoted excess heat by the double bipolar MHDE with a diffuser at 10T was 710 ± 144kJmol-1, whereas as mentioned above, 702 ± 426kJmol-1 was obtained by the same electrode without such a diffuser. From the theoretical excess heat of 1140kJmol-1, the collision efficiencies in pair annihilation were 0.623 ± 0.126 and 0.616 ± 0.374, respectively. From these results, the reproducibility of the thermal measurement was experimentally validated. At the same time, it was concluded that at magnetic fields beyond 10T, the concentration of ionic vacancy and the collision efficiency take constant uppermost values.

Nano-encapsulation of EGCG in dextran 70-stabilized chitosan/SDS nanoparticles: Characterization, permeability behavior and oral bioavailability

Epigallocatechin gallate (EGCG) declares massive health benefits, while poor oral absorption and susceptibility to oxidation and degradation constrained clinical applications. EGCG-encapsulated chitosan/SDS nanoparticles coated with dextran 70（EDCSNs）were here prepared by ionic interaction. The nano-formulations stabilized by dextran 70 presented sizes less than <200 nm, > 30 mV zeta potential, excellent dispersion action and higher encapsulation efficiency, which outdistanced pluronic F-68 as stabilizer. Interaction mechanism of EGCG, chitosan, dextran 70 and SDS in EDCSNs were through hydrogen bond, ion–dipole and electrostatic of opposite charge. Compared with EGCG, EDCSNs demonstrated a superior stability and retention ability with the pH-responsive protection EGCG against degradation under the simulated gastrointestinal fluids. Furthermore, EDCSNs emanated remarkably antioxidant activity and permeability through the intestinal epithelial barrier. Oral administration of nano-formulations in rats evidently increased the plasma Cmax and area under-the-curve 1.95-fold than naked EGCG. Results evidenced that EDCSNs, as a new delivery system, has great potential improvement the stability of EGCG and enhancement the oral absorption and bioavailability.

Heavy-flavor transport and hadronization in pp collisions

Recent experimental results on the Λc+/D0 ratio in proton-proton (pp) collisions have revealed a significant enhancement compared to expectations based on universal fragmentation fractions/functions across different colliding systems, from e+e− to pp. This unexpected enhancement has sparked speculation about the potential effects of a deconfined medium impacting hadronization, previously considered exclusive to heavy-ion collisions. In this study, we propose a novel approach that assumes the formation of a small, deconfined, and expanding fireball even in pp collisions, where charm quarks can undergo rescattering and hadronization. We make use of the same in-medium hadronization mechanism developed for heavy-ion collisions, which involves local color-neutralization through recombination of charm quarks with nearby opposite color charges from the background fireball. Our model incorporates the presence of diquark excitations in the hot medium, which promotes the formation of charmed baryons. Moreover, the recombination process, involving closely aligned partons from the same fluid cell, effectively transfers the collective flow of the system to the final charmed hadrons. We show that this framework can qualitatively reproduce the observed experimental findings in heavy-flavor particle-yield ratios, pT-spectra and elliptic-flow coefficients. Our results provide new, complementary supporting evidence that the collective phenomena observed in small systems naturally have the same origin as those observed in heavy-ion collisions. Published by the American Physical Society 2024

Dual-Sensitive Carbohydrate-Based Nanosystem for Targeted Drug Delivery to Potentiate the Therapeutic Efficacy of Ulcerative Colitis.

Conventional oral formulations for inflammatory bowel disease (IBD) treatment are less than satisfactory, due to the poor controllability of drug release and lack of specificity to the inflammation sites in the gastrointestinal (GI) tract. To overcome these limitations, we developed a multiple carbohydrate-based nanosystem with pH/ROS dual responsibility and charge-mediated targeting ability for IBD-specific drug delivery. In view of the overproduction of ROS and overexpression of cationic proteins in the inflammatory colon, the designed nanosystem was composed of oxidation-sensitive cyclodextrin (OX-CD), chitosan (CS) and pectin (AHP). OX-CD was utilized to load dexamethasone (DM) by the solvent evaporation method. CS and AHP with opposite charges were sequentially coated onto OX-CD to generate the nanosystems by the electrostatic self-assembly method. The physicochemical properties, stability, dual-sensitive drug release behavior, cytotoxicity, cellular uptake and anti-inflammatory activity were investigated in vitro. In vivo bio-distribution and therapeutic efficacy of the nanosystem were further evaluated in the ulcerative colitis (UC) mice. The obtained AHP/CS/OX-CD-DM nanosystem (ACOC-DM) could maintain stability under the GI pH environments, and release drug in the inflammatory colon with pH/ROS sensitivity. Dual polysaccharide-coated ACOC-DM exhibited higher cellular uptake and anti-inflammatory efficacy in macrophages than single polysaccharide-coated CS/OX-CD-DM nanosystem (COC-DM). Orally administrated ACOC-DM could enhance inflammation targeting ability and therapeutic efficacy of DM in the UC mice. This carbohydrate-based nanosystem with pH/ROS dual sensitivity and inflammation targeting capacity may serve as a safe and versatile nanoplatform for IBD therapy.

Relativistic dissipative magnetohydrodynamics from the Boltzmann equation for 2-particle species gas

We derive the equations of motion of relativistic magnetohydrodynamics from the Boltzmann equation using the method of moments. We consider a locally electrically neutral system composed of two particle species with opposite charges, with vanishing dipole moment or spin, so that the fluid has vanishing magnetization and polarization. We find that the dynamics of this fluid changes dramatically in the presence of a magnetic field. The shear stress tensor no longer adheres to a single differential equation; instead, it splits into three non-degenerate components, each evolving according to distinct dynamical equations. Exploring these equations in a Bjorken flow scenario, we find that for large magnetic fields, our theory predicts oscillatory behavior beyond the scope of an Israel-Stewart-like theory.

Charged aggregation‐induced emission luminogens for bioimaging and phototherapy

AbstractAggregation‐induced emission luminogens (AIEgens) have received sustained attention in almost all fields of luminescent materials such as selective biochemical sensors, liquid crystals, and anti‐counterfeiting identification. However, the application of neutral AIEgens in the biomedical field is often greatly limited due to their low water solubility. By introducing charges into AIEgens, AIEgens are endowed with good water solubility as well as specific binding ability to bioorganic molecules or special materials with opposite charges, thus expanding the application range of AIEgens. In this review, we focus on the design strategy of charged AIEgens and then summarize the wide applications of charged AIEgens in light‐guided treatments integrating simultaneous phototherapy and real‐time monitoring of therapeutic efficacy. Finally, we conclude with the challenges and application prospects of charged AIEgens. We hope that this review will provide valuable guidance for further expanding the application of charged AIEgens in the field of biological imaging and phototherapy.

Intermolecular interactions in mixed dye systems and the effects on dye wastewater treatment processes.

Dye wastewater discharge is a critical concern across textiles, paper, cosmetics, and other industries. This study explores the impact of dye-dye interactions on chemical coagulation and ultrafiltration process. Using basic and reactive dyes, representing cationic and anionic compounds, the intricate interplay between these dyes was examined through spectroscopic analysis. Remarkably, interactions between dyes of opposite charges exhibited significant effects on both techniques. Electrostatic attractions played a key role. Positive coagulant hydrolysates selectively attracted negative dyes, while negatively charged membranes effectively captured positive dyes. Combining dyes with opposite charges resulted in enhanced removal efficiency, addressing challenging dyes collectively. This discovery offers a novel approach to improving dye removal, utilizing opposite-charged dye mixtures can tackle stubborn dyes unmanageable by conventional methods.

Конформационная структура полиамфолитов на поверхности сферической металлической наночастицы при одновременном воздействии статического и переменного электрических полей

The simultaneous effect of external static and alternating electric fields on the composite nanosystem "gold spherical nanoparticle-polyampholyte" was studied. Radial and angular dependences of the polymer density were constructed, including in a narrow surface layer of the nanoparticle. In the case where the amplitude of the alternating dipole moment of the nanoparticle significantly exceeded the value of the static dipole moment, a ring-shaped fringe was formed in the equatorial region of the spherical gold nanoparticle. With an increase in the amplitude of the alternating electric field, the shape of the polyampholyte fringe changed from elongated in the direction of static polarization to swollen in the equatorial region of the nanoparticle. Oppositely charged links were located on those halves of the spherical nanoparticle relative to the equator, where opposite charges were induced due to the effect of the static electric field.

Supralinear scaling behavior of ionic transport in membrane nanochannels regulated by outer-surface charges.

The peculiarity of ion transport at the nanoscale is revealed through electrophysiological studies of two biological ion channels: the cation-selective bacterial porin-OmpF and the mitochondrial voltage-dependent anion channel (VDAC). We provide evidence of an unprecedented scaling behavior in the power-law relationship between conductivity and concentration G ∼ c α with α > 1 when functional groups attached to the pore inner wall have opposite charges to those located in the nanochannel's outer surface. Indeed, we find α ∼ 1.4 both for OmpF in positively charged membranes and for VDAC in negatively charged ones. The experiments are analyzed using different levels of theoretical models, starting with an equivalent circuit where total electrical current is described as the sum of ionic currents. Subsequently, we show that electrical circuits incorporating simplifying assumptions such as local electroneutrality and Donnan equilibrium consistently account for the measured G-c relationships yielding extremely similar results to the numerical results of structure-based Poisson-Nernst-Planck equations computed without these assumptions. We demonstrate that unexpected scaling exponents do not correspond to deviations from these classical equilibrium/electroneutrality assumptions, but rather to the structural features of the pore that are not included in oversimplified models in terms of shape and/or charge distribution. In contrast to the predictions of widely accepted models, we demonstrate both experimentally and theoretically that the conductance of ion-selective nanochannels can be drastically reduced in dilute solutions through a mechanism in which membrane charges and pore charges do not compensate for each other but act as interacting sites of opposite charge. Our insights into the critical role of external surface charges aim to open new conceptual avenues for developing nanofluidic devices with enhanced capabilities for energy conversion and sensing properties.

Monte Carlo simulation of the ionization and uptake behavior of cationic oligomers into pH-responsive polyelectrolyte microgels of opposite charge - a model for oligopeptide uptake and release.

External stimuli can tune the uptake and release of guest molecules in microgels. Especially their pH responsiveness makes microgels exciting candidates for drug delivery systems. When both microgel and guest molecules are pH-responsive, predicting the electrostatically driven uptake can be complex since the ionization depends on many parameters. In this work, we performed Metropolis Monte Carlo simulations while systematically varying the pK of the monomers, the concentrations of microgel and guest molecules to obtain a better understanding of the uptake of weak cationic oligomers as a model for oligopeptides into a weak anionic polyelectrolyte microgel. Further, we varied the chain length of the oligomers. The polyelectrolyte networks can take up oligomers when both the network and the oligomers are charged. The presence of both species in the system leads to a mutual enhancement of their ionization. The uptake induces a release of counterions and results in complex formation between the oligomers and the network, leading to the collapse of the networks. Longer oligomers enhance the ionization of the network and, therefore, the complexation. A higher microgel concentration increases the uptake only around the isoelectric point but prevents the uptake due to lower entropy gain at counterion release at higher pH. The results give an insight into the uptake of cationic oligomers into oppositely charged polyelectrolyte microgels and provide hints for the design of anionic microgels as carriers for guest molecules e.g. antimicrobial peptides.

Durable silver nanowire transparent electrodes enabled by biorenewable nanocoating using chitin and cellulose nanofibers for flexible electronics.

The protection of silver nanowire (AgNW) networks is crucial for enhancing their durability and applicability to flexible electronics. In this study, we present a sustainable and efficient strategy to protect AgNW-based flexible transparent electrodes (FTEs) using a layer-by-layer (LBL) assembly of biorenewable chitin and cellulose nanofibers (Chi and Cell). These uniform LBL-assembled thin films were successfully fabricated on AgNW FTEs due to their opposite surface charges. The resulting (Chi/Cell)n bilayers, where n is the number of bilayers, did not degrade the optoelectrical properties of AgNW FTEs and significantly enhanced their stability under various harsh conditions. The optimized (Chi/Cell)10@Al-AgNW FTEs exhibited comprehensive stability against UV/O3 treatment for 40 min, thermal treatment at 250 °C for 350 min, Na2S (1%), HCl (10%), and NH3 (30%) treatments for 3, 30, and 105 min, respectively, sonication for 300 min, and 10 000 cycles of bending test. Therefore, the (Chi/Cell)10@Al-AgNW FTEs were successfully applied to transparent heaters (TH) and pressure sensors with remarkably improved applicability, durability, and performance compared to pristine AgNW FTEs, providing a reassuring solution to the stability issues of AgNW-based FTEs.

Acoustic vortex filter based on tunable metasurfaces

In this paper, we present an acoustic vortex filter (AVF) based on tunable metasurfaces, which can selectively filter the incident multiplexed vortices that carry different orbital angular momentum (OAM). Our metasurface-based AVF is composed of an upper acoustic metasurface (UAM) and a lower acoustic metasurface, of which the intrinsic topological charge (ITC) can be tuned by mechanically rotating the UAM along its central axis. Due to the critical order of the propagating vortex modes in waveguide, controlling the ITC of the AVF allows for the selective filtering of incoming multiplexed acoustic vortex beams based on the sound vortex diffraction in phase-gradient metasurface, which endows the vortex filter the capability that let the incident vortex of specific OAM pass through it. In the following demonstration, both in theory and experiment, we design the AVF and effectively filter the acoustic vortices with two opposite topological charges by simply altering the orientation angle of the UAM. Based on this, we further demonstrate its application in asymmetric acoustic wave transmission. Our work offers an approach to selectively filter the incident acoustic vortex, which improves the capability to control the acoustic OAM via metasurfaces.

A new material built with alternating Cu sulfide and (Al,Mg) hydroxide molecular sheets: hydrothermal synthesis and selected characteristics.

Two-dimensional materials with new physical phenomena are gaining popularity due to their unique properties. In recent years, a new family of layered compounds inspired by the minerals valleriite and tochilinite which are composed of alternating quasi-atomic sheets of transition metal chalcogenides (sulfides and selenides of Fe, Fe-Cu and other metals) and hydroxides of Mg, Al, Fe, Li, etc., assembled via electrostatic interaction, has arisen as a new synthetic platform for 2D materials. In this work, we synthesized a new promising material composed of alternating quasi two-dimensional sulfide Cu4-xS2 (x = 1-1.5) and hydroxide (Mg1-yAly)(OH)2 (y ∼ 0.25) sheets as multilayer flakes with a lateral size of 1-2 μm and a thickness of several tens of nm. The reliable formation of the material was ensured by an excess of aqueous sodium sulfide along with some quantity of Al salt, which was necessary for the self-assembly of the sulfide and hydroxide sheets driven by their opposite electric charges. A series of samples with varying Al/Mg ratios were examined using TEM, EDS, SAED, XRD, XPS, Raman and UV-vis-NIR spectroscopy. Using the Rietveld refinement procedure, the crystal lattice was determined to resemble the space group P3̄m1 with cell parameters a = b = 3.89 Å and a = b = 3.03 Å for sulfide and hydroxide parts, respectively, and the common parameter c = 12.03 Å. XPS and Raman spectra agree with the chalcocite-like sulfide layers containing Cu+ cations, monosulfide anions and few, if any, S-S bonds. UV-vis-NIR spectra show indirect transitions of 0.8 eV and considerable absorption in the near-infrared region. Thermogravimetry and differential scanning calorimetry studies under an Ar atmosphere suggest a slightly endothermic process and a phase transition at 90 °C accompanied, as suggested by conductivity measurements, by a metal-semiconductor transition; the main destruction with a loss up to 15 wt% occurs at ∼510 °C, due to decomposition of hydroxide layers similar to layered valleriite and tochilinite. The (thermo)electrical data show that, contrary to valleriite, which is an n-type semiconductor with mediocre thermoelectric performance, the proposed material is a heavily doped p-type semiconductor exhibiting good thermoelectric efficiency. The new member of the valleriite family of heterolayered quasi-2D materials demonstrates therefore essentially novel promising properties.

Heavy-flavor transport and hadronization in a small fireball

We study heavy-flavor hadron production in high-energy pp collisions, assuming the formation of a small, deconfined and expanding fireball where charm quarks can undergo rescattering and hadronization. We adopt the same in-medium hadronization mechanism developed for heavy-ion collisions, which involves Local Color-Neutralization (LCN) through recombination of charm quarks with nearby opposite color charges from the background fireball. Diquark excitations in the hot medium favor the formation of charmed baryons. The recombination process, involving closely aligned partons from the same fluid cell, effectively transfers the collective flow of the system to the final charmed hadrons. This framework can qualitatively reproduce the observed experimental findings in heavy-flavor particle-yield ratios, pT -spectra and ellipticflow coefficients. Our results provide new, complementary support to the idea that the collective phenomena observed in small systems have the same origin as those observed in heavy-ion collisions.

Electric field-modulated evaporative thin film deposition of bio-particles for piezoelectric applications.

Bio-based functional materials can be used to replace or limit the use of synthetic materials sourced from unsustainable sources. However, the potential of such materials remains largely unexplored. In this study, we demonstrate the use of weak AC electric fields to deposit ultra-thin piezoelectric films from cellulose nanocrystals (CNC). This is the first time electric fields are used to realize <50 nm thick uniform bio-based piezoelectric films wherein the bioparticles exhibit unidirectional arrangement. Interestingly, we found that the use of weak AC electric fields of suitable frequencies completely mitigates the coffee ring effect (CRE), which results in defect-free uniform ultra-thin films. Additionally, the electric fields appear to help in realizing unidirectional alignment of particles in the films, which enhances their piezoelectric properties. The method was also tested for chitin nanocrystals (ChNC), which have a similar aspect ratio but bear opposite polarity surface charges, and the influence of the field on coffee ring formation and particle orientation in CNC thin film deposition was validated. The phenomena can be attributed to the constant spatio-temporal curvature of the evaporating liquid film, the transient state between the three-phase contact (TPC) line, the electric field-dependent contact angle, and the permanent and field-induced dipole moments. These factors lead to particle polarization and alignment. The films have an optimum electrical frequency of deposition at which they are continuous and uniformly thin, have unidirectional alignment of particles, and function as a single dipole.

Monometallic ‘zinc oxide and copper oxide’ nanoparticles by ecofriendly synthesis for suppression of mastitis-causing bacteria via ξ potential

Background Metallic nanoparticles (MNPs) are extensively employed in biology and medicine because they may freely pass through organisms’ barriers. Monometallic zinc oxide (MM ZnO) and copper oxide nanoparticles (CuO NPs) by ecofriendly synthesis are safe, economical, and promising future alternatives as antimicrobial agents. Objective This study focused on the functioning zeta (ξ) potential (ZP) of (MM ZnO) and (CuO NPs) for suppression of mastitis-causing bacteria. Materials and methods Monometallic nanoparticles (MMNPs) were biosynthesized by Bacillus megaterium and characterized by UV-Vis spectra, SEM-EDS, TEM, particle size distribution, ZP, and particle concentrations calculated by ICP-AES. Then, the biocidal activity of MM ZnO and CuO NPs against some mastitis causing bacteria isolates was studied. Results and conclusion The obtained data reveal that the resulting cationic ZnO and anionic CuO are zero-dimensional (0-D) oval and spherical NPs with 5–17 and 10–34 nm in size, respectively. The IC50 of the biosynthesized ZnO and CuO NPs was 1717±33.7 μg/ml and 1493±42.52 μg/ml, respectively. The obtained results showed no cytotoxic effect of the MMNPs on somatic cells. Data suggested that a high dose of 100 μg/ml of cationic ZnO represents a highly significant effect (P&lt;0.05) over anionic CuO for suppressing mastitis bacteria. The terminus point was in evaluating the toxicity of MMNPs by comet assay; the effects of the variation were based on the ZP and interactivity of layers carrying opposite charges. These findings elucidate that cationic ZnO NPs have advantages in targeting pathogenic bacteria because of enhanced delivery to the cells, which causes water dehydration and decreases the moisture required for bacterial viability and plasmolysis via ionic interactions.

Multifunctional droplet handling on surface-charge-graphic-decorated porous papers.

Developing a fluidic platform that combines high-throughput with reconfigurability is essential for a wide range of cutting-edge applications, but achieving both capabilities simultaneously remains a significant challenge. Herein, we propose a novel and unique method for droplet manipulation via drawing surface charge graphics on electrode-free papers in a contactless way. We find that opposite charge graphics can be written and retained on the surface layer of porous insulating paper by a controlled charge depositing method. The retained charge graphics result in high-resolution patterning of electrostatic potential wells (EPWs) on the hydrophobic porous surface, allowing for digital and high-throughput droplet handling. Since the charge graphics can be written/projected dynamically and simultaneously in large areas, allowing for on-demand and real-time reconfiguration of EPWs, we are able to develop a charge-graphic fluidic platform with both high reconfigurability and high throughput. The advantages and application potential of the platform have been demonstrated in chemical detection and dynamically controllable fluidic networks.