Anodic Formation Research Articles

Pulsed-Current Operation Enhances H2O2 Production on a Boron-Doped Diamond Mesh Anode in a Zero-Gap PEM Electrolyzer.

A niobium (Nb) mesh electrode was coated with boron-doped diamond (BDD) using chemical vapor deposition in a custom-built hot-filament reactor. The BDD-functionalized mesh was tested in a zero-gap electrolysis configuration and evaluated for the anodic formation of H2O2 by selective oxidation of water, including the analysis of the effects on Faradaic efficiency towards H2O2 (FEH2O2) induced by pulsed electrolysis. A low electrolyte flow rate (V⋅anolyte) was found to result in a relatively high concentration of H2O2 in single-pass electrolysis experiments. Regarding pulsed electrolysis, we show an optimal ratio of on-time to off-time to obtain the highest concentration of H2O2. Off-times that are "too short" result in decreased FEH2O2, whereas "too long" off-times dilute the product in the electrolyte stream. Using our electrolyzer setup with an anodic pulse of 2 s with 4 s intervals, and a V⋅anolyte of 0.75 cm3 min-1, resulted in the best performance. This adjustment increased the FEH2O2 by 70 % compared to constant current electrolysis, at industrially relevant current densities (150 mA cm-2). Fine tuning of BDD morphology, flow patterns, and anolyte composition might further increase the performance of zero-gap electrolyzers in pulsed operation modes.

2D P-doped carbon nitride as an effective artificial solid electrolyte interphase for the protection of Li anodes.

Metallic lithium plays an important role in the development of next-generation lithium metal-based batteries. However, the uncontrolled growth of lithium dendrites limits the use of lithium metal as an anode. In this context, a stable solid electrolyte interphase (SEI) is crucial for regulating dendrite formation, stability, and cyclability of lithium metal anodes. This article proposes an artificial protective layer of P-doped carbon nitride on the lithium anode surface to address these issues. A thin film of P-doped carbon nitride (CNP) was created through a simple drop-casting method using synthesized CNP powder, forming an artificial SEI on the lithium electrode. The resulting symmetric CNP-modified Li/Li cells exhibited remarkable cyclability with low overpotentials of around 40 mV over 500 cycles at a current density of 3 mA cm-2. Anode degradation and SEI composition were thoroughly studied for cycled electrodes to gain insight into the mechanisms underlying this modified surface. Furthermore, these CNP-modified anodes were successfully utilized in a Li-S coin cell battery, achieving high capacity and capacity retention at a high current density (1C). First-principles calculations indicate that P-doping in the carbon nitride structure significantly enhances the surface diffusion of lithium and promotes more homogeneous lithium plating.

Advanced temporal analysis of anode activity during mode transitions in high current vacuum arcs

Abstract Anode activity in high current vacuum arcs leads to the formation of various high current modes and transitions between them. Intense material evaporation during the anode spot mode and formation of a neutral vapour cloud during the anode plume mode modify the arc plasma properties and, hence, can have a crucial impact in applications, like e.g. reduction of interruption performance of switching devices. The influence of anode mode appearance on arc plasma parameters and on anode surface temperature was studied in detail by a novel optical diagnostic technique—intensified video optical emission spectroscopy. Employing advanced diagnostic methods, the ground state density, excitation temperature and pressure profiles close to the anode surface have been determined. For the anode plume mode, higher copper vapour pressure was found in the plume shell compared to its core. The copper ion density distribution shows a maximum outside of the plume shell. Consequently, a higher electrical conductivity in the surrounding area of the plume might be expected, i.e. the arc current flows around the plume rather than through it. Analysis of the temporal evolution of electrical and optical signals reveals that voltage jumps and drops during the mode transitions are accompanied by noticeable changes in the anode surface temperature. Thus, the formation of the anode plume leads to temperature lowering while the transition to the anode spot mode is accompanied by a temperature increase. In general, a clear correlation between electrode surface temperature and arc voltage in the case of constricted anode attachment is found. The results of this study give new insights into anode plume properties and consequences of anode mode transitions. Reversible mode transitions and correlations between arc voltage and anode surface temperature, as well as changes in the current path during anode plume mode, have to be considered as factors for optimization of electrode design and choice of materials for switching applications.

Anodic Porous NiO Film Formation for the Hexavalent Chromium Removal under Ultraviolet Irradiation

Abstract Anodic porous nickel oxide (NiO) was grown by anodization of Ni in ethylene glycol (EG) added to NH4F at 60 V in a two-step anodic process. The first process produced hydrated anodic film which was removed before the foil was subjected to a second anodic process. This led to the formation of porous structure with pore diameters of ∼ 90-180 nm. Formation of porous structure was done as to provide a larger specific surface area that can increase the removal efficiency of the hexavalent chromium. The as-anodized anodic film was then annealed at 300 °C to improve the adhesion of nickel oxides porous to substrates before being used as a photocatalyst to reduce Cr(VI) in a synthetic wastewater under ultraviolet (UV) irradiation. Porous NiO showed a good photocatalyst performance in reducing Cr(VI) to Cr(III) with 60% reduction after 150 min. However, with the addition of ethylenediaminetetraacetic acid (EDTA), 100% reduction was achieved after 120 min indicating that EDTA is required as holes scavengers.

Enhancing Stability in Aqueous Zn Ion Batteries: Insights into Two-Dimensional Nanomaterials Protective Layer

Zinc-ion Batteries (ZIBs) have emerged as promising candidates for next-generation energy storage systems, offering affordability and safety. However, the practical applications of Zn metal as anode is impeded by significant challenges such as side reactions and dendrite growth. We propose a novel approach that employs two-dimensional (2D) nanomaterials protective layer (BN, MoS2, MXene) to mitigate dendrite formation and side reactions (hydrogen evolution, corrosion) of Zn metal anode, facilitating controlled Zn ion flux during charge/discharge cycles. Our findings particularly highlight the MoS2@Zn anode, which demonstrates stable cycling performance for over 1000 hours at a current density of 1 mA/cm² with a capacity of 1 mAh/cm². This anode effectively inhibits dendrite growth and suppresses side reactions such as hydrogen evolution and corrosion. Additionally, when integrated into a full cell configuration with a MnO₂ cathode, the MoS₂@Zn anode exhibits exceptional capacity retention, maintaining nearly 100% of its initial capacity even after 100 cycles. This work contributes to the advancement of metal-based aqueous battery technologies by demonstrating the practical applicability of 2D material protection layers in improving the performance and reliability of ZIBs.AcknowledgementThis work was supported by the Commercialization Promotion Agency for R&D Outcomes(COMPA) grant funded by the Korean Government(Ministery of Science and ICT). (RS-2023-00304768) and the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(No. RS-2023-00217581).

Magnetism-Induced Homogenization of Charge and Ionic Distributions Realized By Cu-Ni Core-Shell Nano-Necklace for Stable Lithium Metal Batteries

One-dimensional nanostructures such as nanowires and nanobelts exhibit unique characteristics. Nano-necklace structures, in particular, have demonstrated superior properties in certain applications compared to nanowire structures due to their enlarged active sites and surface area, ample transport channels as well as, multiscale surficial roughness.Various methods exist for fabricating nano-necklace structures, including chemical synthesis, self-assembly, template assistance, and electrospinning. The method we approached was to modify the chemical reduction method in an economical, facile, and quick way for large scale synthesis. In our synthetic approach, we utilized ethylenediamine as a capping and shape-directing agent in a strong base solution, which enable the mass production of Cu-Ni core-shell nano-necklace (CNNN) with a high yield within 30 minutes. Moreover, by changing the type of basic solution, we successfully obtained Cu-Ni core-shell nanowire (CNNW) as a typical 1D nanostructure.The physiochemical properties of as-obtained CNNN and CNNW were systematically investigated. Microscopic analyses demonstrated that both CNNN and CNNW are constituted by two major components: 1) surficial Ni coating layers with a thickness of about 40 nm and 2) inner Cu clusters as a shell and a core, respectively. Experimental results suggest that CNNN exhibits much stronger ferromagnetic properties with much higher specific surface area compared to CNNN, which hold potentials for various applications.To demonstrate one of the potential applications of CNNN, we employed CNNN as a charge and ionic re-distributor for stable lithium metal batteries (LMB). The electrochemical analyses demonstrated that CNNN enabled uniform charge and ionic distributions when coated on a commercial separator, which suppresses notorious dendrite formation of Li metal anodes, due to its excellent ferromagnetic properties and enlarged active sites with Li ions. Therefore, CNNN enabled the stable operation of LMB with LiFePO4 and LiNi8Co1Mn1O2 cathode. Figure 1

Formation Efficiency of Anodic Alumina in Acidic Electrolyte Containing Amino Acid

Anodic porous alumina films, which are formed by anodization in acidic solution, provide hardness, wear resistance and corrosion resistance for the surface of aluminum used for automobile and aircraft parts. For instance, to increase the hardness of anodic films on aluminum, the anodization is industrially carried out at low temperature to avoid chemical dissolution of the film during anodization. From a perspective of energy conservation and decarbonization, an important objective are to reduce energy costs and improve work efficiency. Our group has reported that the addition of alcohol (e.g., methanol, ethanol, and ethylene glycol) to an electrolyte improves the formation efficiency and hardness of the film at 20 °C 1, 2). In this study, we focused on amino acids that having inhibitability of aluminum corrosion by adsorbing on the surface of aluminum in a mixed acid containing chloride ion 3). The effects of types and concentrations of amino acids on the anodization voltage, formation efficiency (coating ratio) and structure of the porous alumina were investigated. The sulfuric acid and oxalic acid were used as electrolytes, each containing various amino acids (e.g., glycine, α-alanine, and β-alanine). The electrolyte was maintained at a constant temperature of 20 °C using a thermostat and gently stirred at 300 rpm using a magnetic stirrer to accelerate the diffusion of the heat evolved during the anodization.For example, anodization was conducted in 1.5 mol dm–3 sulfuric acid at 100 A m–2. After anodization for 60 min, the final voltage was 15 V. Even when 100 mmol glycine was added to sulfuric acid, the final voltage was almost the same as sulfuric acid alone. For sulfuric acid containing 800 mmol glycine, however, the final voltage (22 V) was higher than that for sulfuric acid alone. When the concentration of amino acid became high, the viscosity of the electrolyte increased, while the conductivity decreased. Even in the oxalic acid-based electrolyte, the tendency of amino acid concentration dependence of voltage was the same as that of sulfuric acid-based electrolyte. These results indicate that the increased final voltage can be attributed to the high solution resistance of the electrolyte used for anodization. The formation efficiency (coating ratio) and hardness of anodic film formed in acidic electrolyte containing amino acids will also be discussed.1) Matsumoto, H. Hashimoto, H. Asoh, J. Electrochem. Soc., 167, 041504 (2020).2) Asoh, T. Sano, J. Electrochem. Soc., 168, 103506 (2021).3) Ashassi-Sorkhabi, Z. Ghasemi, D. Seifzadeh, Appl. Surf. Sci., 249, 408–418 (2005).

Shining Light on New Additives for Lithium Sulfur Batteries through Polysulfide Shuttle Tracking Operando Optical Fluorescence Microscopy

Lithium Sulfur (Li-S) batteries are uniquely poised to provide exciting new opportunities in the field of energy storage, possessing an impressive theoretical gravimetric specific capacity an order of magnitude greater than current lithium-ion batteries (1672 mA h g-1), and energy density over 5 times higher (2567 Wh kg-1), while also using far safer and more sustainable materials.However, their wilder proliferation and commercialisation suffers heavily from the polysulfide shuttle effect, where the lithium polysulfide intermediates generated at the cathode during the conversion mechanism of Li-S operation dissolve into the battery electrolyte and diffuse towards the lithium metal anode. This leads to parasitic reactions between the polysulfides and the anode, causing rapid cell degradation from active material loss, degradation of the anode solid electrolyte interface (SEI), and subsequent rapid dendrite formation. The shuttle effect is a primary mechanism of cell failure, and as such, most research into Li-S focuses on its mitigation. Current methods of characterizing the shuttle effect provide limited detail or are overly time consuming, so more robust characterization methods are required to further understand the distribution, dynamics, and degree of polysulfide transport.Here, the newly established Optical Fluorescence Microscopy (OFM) technique, for visualising the spatial distribution of polysulfides within the Li-S electrolyte and through sufficiently large cathode pores during operando cycling, is utilised for facile assessment of the efficacy of a variety of additives to Li-S batteries in reducing the polysulfide shuttle effect. Using a polysulfide sensitive fluorescent dye, established to be inert to both the components of a Li-S battery and the additives, the intermediate polysulfides formed throughout cycling can be made to fluoresce, and thus directly visualised. The correlation between fluorescence intensity and polysulfide concentration is also linear when below the linear concentration range of the dye, allowing for polysulfide concentration to be spatially quantified through use of a calibration curve. This enables direct observation of the kinetics of sulfur dissolution and the subsequent diffusion towards the anode and dendrite formation, and thus measurement of the efficacy of steps taken to prevent this.The effects of various additives are elucidated using this method – including the standard LiNO3 additive in sacrificially protecting the lithium anode through SEI formation, as well as novel fibroin-based additives trapping polysulfides within the cathode. Further, the total lack of solubilised intermediate polysulfides within the electrolyte potentially granted by a quasi-solid-state Li-S morphology is assessed through OFM. As is the impact of catalytic additives on the kinetics of the Li-S conversion mechanism, through reduction in the time polysulfides spend in the solubilised state. With OFM, one can directly and conveniently assess the real-time spatial distribution, dynamics, and degree of polysulfide transport in a cycling Li-S cell far faster and significantly easier then would be possible with other methods, and with a very robust dataset. OFM is thus an ideal platform for the development of polysulfide shuttle mitigation strategies, allowing rapid iteration of mitigation methods such as new additives or cathode morphologies. It has the potential for a widespread impact in the field of Li-S batteries, in both industry and academia, through collaboration with and usage by other researchers developing shuttle mitigation techniques. Figure 1

Nature of Instability in Electrokinetics-Based Anodic Oxide Pore Formation

The anodization process of aluminium in acidic electrolytes facilitates the formation of nano-porous aluminium oxide. A simplified model for anodization is formulated, incorporating essential physics such as high field conduction, Butler-Volmer electrokinetics for oxide formation and dissolution at the oxide-electrolyte interface, effect of Laplace pressure on the activation energy of oxide-electrolyte interfacial reactions. A linear stability analysis suggests that the oxide film is rendered unstable to perturbations of well-defined wavelength for specific range of parameters such as anodizing efficiency, applied voltage and electrolyte pH. The analysis is then extended to the weakly nonlinear regime to determine the nature of instability, i.e., whether it is subcritical or supercritical instability beyond the stability threshold. Our findings indicate that the solutions arising from neutral stability exhibit a subcritical nature (cf. Figure 1), in agreement with experimental observations of pore formation. Figure 1

Impact of Formation Cycle Current Density on the Cycling Stability of Zero-Excess Li-Metal Batteries

Zero-excess Li-metal batteries (ZELMBs) are promising candidates for next-generation batteries with high energy densities and improved safety during cell manufacturing. However, the loss of Li that occurs during the initial anode formation hinders the practical application of this system and considerably affects the cycling stability. In this study, we optimize the initial formation of the anode using a formation protocol designed by controlling the charging current density and investigating its effect on cycling stability. This study provides insight into the behavior of ZELMBs and highlights the necessity for a tailored initial formation protocol for each electrolyte.

Understanding and Controlling Stack Pressure Inhomogeneity in Anode-Free Solid-State Batteries

Lithium (Li) metal anodes are widely studied as replacements for current graphite anodes as they have projected higher energy density. However, Li-metal batteries face issues with dendrite propagation and the eventual formation of dead Li. Solid-state batteries (SSBs) are a promising pathway to realize Li-metal batteries, which is attributed to their ability to improve safety and stability through the use of solid-state electrolytes. In particular, “anode-free” SSBs can enable high energy densities by forming a Li metal anode in situ. The initial Li nucleation, plating, and stripping behaviors in anode-free SSBs is influenced not only by the interfacial electrochemistry, but also by the mechanical stresses present along the current collector interface. Mechanical stress also plays a key role in Li metal anode deformation, where creep is the dominant deformation mechanism. However, to date, stack pressure is typically reported as a singular value, rather than considering the temporal and spatial variations in interfacial stress as the battery cycles.This work investigates the role of inhomogeneous stack pressure on Li anode formation and dissolution against a sulfide solid electrolyte. To compensate for this inhomogeneous stack pressure, elastomeric interlayers are used to increase the uniformity of stress along the interface, and thus improve electrochemical cyclability. To analyze the impact of elastomeric interlayers on areal Li plating coverage, post-mortem optical microscopy images of the current collector are captured, showing an improvement in areal coverage from 49% to 70%. The reversible capacity also increases from 89% to 94% with inclusion of an elastomer layer. To confirm the trends in an elastomer layer on increasing stack pressure homogeneity, the mechanical stress at the anode-free interface is modeled using finite-element simulations under different stack pressure geometries. System-level simulations illustrate tradeoffs with respect to the uniformity of mechanical stress and energy density. This work demonstrates the importance of studying external auxiliary components and packaging in SSBs to optimize anode-free SSB performance.

Bi-Functional Interfacial Modification Enables Highly-Exposed Zn(002) Crystal Facet Towards Durable Zn Metal Batteries.

Zn-ion batteries (ZIBs) have garnered growing interest in large-scale energy storage devices for the high safety, high theoretical capacity and low electrochemical potential. Nevertheless, their widespread applications are significantly impeded by dendrite formation, hydrogen evolution and corrosion reactions of Zn anodes. Herein, a bi-functional polyacrylic acid (PAA) modified-Zn anode (Zn-PAA) is designed to concurrently inhibit Zn dendrite formation and alleviate side reactions for durable ZIBs. The bi-functional PAA coating not only selectively acid-etches the active Zn crystal facets to guide the planar deposition along the highly-exposed Zn(002) crystal facet, but also facilitate uniform Zn deposition through coordination between the polymer functional groups and Zn2+. Meanwhile, the electrically-insulated PAA protective layer effectively separates Zn anodes from the electrolyte and modulates the solvation structure of Zn2+.6H2O, significantly suppressing side reactions. Consequently, the assembled Zn-PAA//Zn-PAA symmetrical cell delivers an outstanding cycling stability of 1600 h at 1 mA cm-2 and 1 mAh cm-2. The assembled KVO//Zn-PAA full cell shows exceptional cycling stability over 1500 cycles at 2.0 A g-1 with a high Coulombic efficiency approaching 100 %. The facile bi-functional surface modification strategy, which enables to finely tune the crystal facet texture and ion distribution manner, opens up a groundbreaking path towards safe and durable ZIBs.

Copper Oxides on Brasses of Different Phase Composition: Anode Formation and Photoelectrocatalytic Activity

Copper Oxides on Brasses of Different Phase Composition: Anode Formation and Photoelectrocatalytic Activity

Electrokinetics-Driven Anodic Oxide Pore Formation: Linear and Weakly Nonlinear Analysis

Anodization of aluminum in an acidic medium facilitates the formation of well-ordered nanoporous anodic oxide films. The mechanism of pore formation is investigated as a morphological instability using a simplified model. The model accounts for the high field conduction law and field-assisted reactions (oxide formation/dissolution) only at the oxide-solution interface. The role of Butler-Volmer electrokinetics, electrolyte pH, anodic efficiency, and interface curvature on reaction kinetics are taken into account. Linear stability analysis suggests that the oxide film is unstable to well-defined wavelengths in specific ranges of parameters such as anodizing efficiency, applied voltage and electrolyte pH. Subsequently, a weakly nonlinear analysis is carried out to determine the nature of bifurcation beyond the stability threshold. Our findings indicate that the instability exhibits a subcritical nature, well in agreement with experimental observations.

Enhancement of Lithium-Mediated Nitrogen Reduction by Modifying Center Atom of Tetraalkyl-Type Ionic Liquids.

The lithium-mediated nitrogen reduction reaction (Li-NRR) offers a viable alternative to the Haber-Bosch process for ammonia production. However, ethanol, a common proton carrier in Li-NRR, exhibits electrochemical instability, leading to oxidation at the anode or byproduct formation at the cathode. This study replaces alcoholic proton carriers with ionic liquids (ILs), specifically tetrabutylphosphonium chloride (TBPCl) and tetrabutylammonium chloride (TBACl), to examine how the electronegativity differences between the central atom and adjacent carbon of the cation affect catalytic performance. The results show that switching the central atom in tetraalkyl-type ILs markedly enhances performance, specifically resulting in a 1.45-fold increase in Faradaic efficiency (FE) with the transition from phosphonium to ammonium cation of ILs. Additionally, optimal IL concentrations in the electrolyte are identified to maximize ammonia yield. TBACl, in particular, demonstrates enhanced ammonia production and operational stability, achieving an ammonia yield rate of 13.60 nmol/cm2/s, an FE of 39.5 %, and operational stability for over 12 h under conditions of 10 mA/cm2 and 10 atm. This research underscores the potential of precise IL modifications for more efficient and sustainable Li-NRR.

Enhancement of Lithium‐Mediated Nitrogen Reduction by Modifying Center Atom of Tetraalkyl‐Type Ionic Liquids

AbstractThe lithium‐mediated nitrogen reduction reaction (Li‐NRR) offers a viable alternative to the Haber–Bosch process for ammonia production. However, ethanol, a common proton carrier in Li‐NRR, exhibits electrochemical instability, leading to oxidation at the anode or byproduct formation at the cathode. This study replaces alcoholic proton carriers with ionic liquids (ILs), specifically tetrabutylphosphonium chloride (TBPCl) and tetrabutylammonium chloride (TBACl), to examine how the electronegativity differences between the central atom and adjacent carbon of the cation affect catalytic performance. The results show that switching the central atom in tetraalkyl‐type ILs markedly enhances performance, specifically resulting in a 1.45‐fold increase in Faradaic efficiency (FE) with the transition from phosphonium to ammonium cation of ILs. Additionally, optimal IL concentrations in the electrolyte are identified to maximize ammonia yield. TBACl, in particular, demonstrates enhanced ammonia production and operational stability, achieving an ammonia yield rate of 13.60 nmol/cm2/s, an FE of 39.5 %, and operational stability for over 12 h under conditions of 10 mA/cm2 and 10 atm. This research underscores the potential of precise IL modifications for more efficient and sustainable Li‐NRR.

Mechanistic Analysis of Anodic Oxidation of Gold in KOH (0.1 M) Solution Using the Point Defect Model

The potentiostatic, anodic formation of gold oxide at potentials of 0.55 to 0.80 V versus SHE in aqueous KOH (0.1 M) was studied using an impedance-based Point Defect Model (PDM). The film thickness and refractive indices at each formation potential were estimated using spectroscopic ellipsometry. The thickness of the oxide increases linearly with increasing applied voltage within this range. Mott-Schottky (MS) analysis showed that gold oxide formed in KOH (0.1 M) is an n-type semiconductor, and the dominant defect (Aui3+) density is calculated to be in the order of 1021–1022 (1/cm3). The steady-state current density of the oxide formation was independent of voltage, also in agreement with an n-type oxide. Reasonable agreement between PDM predictions and experimental observations of dominant defect density, steady-state current density, and thickness, demonstrates the value of the PDM in this system.

Formation of incipient anodes in localized mortar repairs with the addition of rice husk silica

The objective of this work was to investigate how incipient anodes can be detected and monitored in localized repair areas using mortars with added rice husk silica. Three repair conditions were tested on prismatic specimens: without repair, with repair without rice husk silica addition, and with rice husk silica addition in the mortar. Corrosion potential and electrical resistivity tests were conducted. The corrosion potential test showed no variation along the bar, while the electrical resistivity test showed varied values depending on the repaired and non-repaired zones. It was concluded that adding rice husk silica to the mortar made the corrosion potential more electronegative due to the greater difference in electrical resistivity compared to the substrate, contributing to the formation of incipient anodes.

(Invited) Development of Mildly Acidic Aqueous Zinc Batteries: Anode, Cathode, and Electrolyte

Aqueous zinc batteries use earth abundant materials and has stable supply chains, making them one of the promising battery technologies for grid-scale energy storage applications. However, the limited cycle life because of the dendrite formation of zinc anodes, poor reversibility of cathodes, and consumption of electrolyte has greatly hampered its practical application. Recently, extensive research effort has been made on the development of rechargeable alkaline batteries and mildly acidic zinc ion batteries. Novel structured zinc anodes, intercalation cathode materials and new electrolytes have been developed to improve the performance. Here, we would like to present our effort towards aqueous zinc batteries under practical conditions. Zinc alloy anodes, organic cathode materials, and the use of new binders and electrolyte additives will be discussed.

Characterization of a radially emitting spray jet in a cylindrical inertial electrostatic confinement plasma source based on particle in cell simulation

This paper investigates the outflow mechanism of a cylindrical inertial electrostatic confinement plasma source using Particle in Cell plasma simulations. Various phenomena such as ion-wall interactions, impact ionization, excitation, and secondary electron generation are considered. Together with a fine time and cell resolution to reveal relevant phenomena. The results indicate a high electron and ion density in front of the cathode at the widest grid opening, which suggests the formation of a cascade-like charge carrier emission, commonly referred to as the “spray jet”. Initially, a virtual anode is formed within the cathode grid and is shifted toward the grid opening as time elapsed. Ions are accelerated in the plasma sheath around the cathode and collide with the cathode grids or oscillate through the grid opening. Electrons are accelerated and ionize the background gas at the plasma sheath edge. While the electron flow is disordered within the cathode it forms a cascade-like quasi-neutral plasma at the outlet of the plasma source. Through the formation of a virtual anode the discharge becomes self-sustained. With this simulation results the working principle of the inertial electrostatic confinement plasma source can be derived.