Graphite Layers Research Articles

EVALUATION OF THE GRAPHENE DISPERSIONS FOR KEVLAR FABRICS FUNCTIONALIZATION OBTAINED BY THE LIQUID-EXFOLIATION OF GRAPHITE

The process where pristine graphite is subjected to a solvent treatment seems simple and scalable and has attracted the attention of researchers over many years. However, for successful exfoliation, overcoming the van der Waals attractions between the adjacent layers of graphite is necessary. Over time, several methods have been created to overcome the attraction between layers. Graphene’s liquid phase exfoliation (LPE) occurs due to the strong interactions between the solvent molecules and the basal planes of graphite, overcoming the energetic resistance to exfoliation and subsequent dispersion. Ultra sonication used for exfoliation can produce single or few layered graphene flakes. During sonication the sound waves propagate through liquid medium in alternating high- and low-pressure cycles, strong mechanical and thermal energy released by acoustic cavitation results in splitting up large particles into fine ones and dispersing them. Simultaneous insertion of solvent and/or intercalation molecules in between the graphite layers takes place supporting graphite separation into graphene layers. ; The dispersion capacity of graphene flakes depends on how appropriate the solvent properties are to the corresponding properties of graphene, such as surface tension, Hildebrand, and Hansen solubility parameters. Only certain solvents can disperse graphene well and form a dispersion appropriate for specific future applications. In addition, after exfoliation by ultra sonication graphene flakes aggregation due to the van der Waals attractions must be overcome to prepare in long-term stable dispersions of nanometres-size graphene sheets. ; The research has focused on the preparation of stable dispersion ready for transfer without intermediate processes to the Kevlar fabrics. An experimental comparison of the potentials of the 4 solvents for the application resulted in three corresponding to the intended use, two of them examined in detail, supplementing the composition of the LPE liquid medium with triethanolamine to obtain sufficient performance graphene coverage on Kevlar textile fibres.

Synthesis and electrochemical properties of activated lignite carbons-reduced graphene oxide nanocomposites symmetric supercapacitors

Ultra-fast chargeable or rechargeable symmetric carbon-based supercapacitors (SCSs) with high capacity, inexpensive, and non-flammability have attracted much attention for electronics and energy storage devices. However, improving both high redox reaction and ion transport/diffusion processes by enhancing high energy storage performance and rapid ion/electron transport SCSs electrode materials remains challenging. Herein, we presented a successful preparation of activated lignite carbons-reduced graphene oxide (ALC-rGO) nanocomposite (NCp) with the ALC:rGO ratio of 80:20 wt% by a one-pot hydrothermal for high electrochemical performance. Importantly, the matrix of ALC-rGO NCp was primary amorphous carbon with hexagonal graphitic layers and pore structures of plentiful micropores and mesopores. Remarkably, the ALC-rGO NCp electrode exhibited a maximum specific capacitance (Csc) of 152.12 F/g at 0.5 A/g. Interestingly, the SCSs-ACL-rGO device could illustrate a good performance at a potential voltage of 1.8 V with Csc of 50.90 F/g at 1 A/g and capacity retention of 96.0 % at 5 A/g after 2,000 cycles GCD test.

Towards realistic structural char models: Generation of stacked graphene-like layers using constrained reactive molecular dynamics simulations

For a molecular understanding of coal combustion, realistic coal and char models are pivotal. We propose a novel top-down method for the construction of char models, consisting of stacked graphene-like layers with defects. We start on the mesoscale with corrugated stacked surfaces as a template. Then the carbon atoms are pre-positioned on these surfaces and surrounded by hydrogen atoms. In a constrained reactive MD simulation the carbon atoms are then rearranged into a chemically reasonable state with dangling bonds saturated by hydrogen atoms. Importantly, the initial shape of the template is maintained to a great extent, leading to a substantial amount of defects in the graphitic planes, especially for high curvatures. In a final step, small molecular fragments and unfavorable arrangements are removed and remaining dangling bonds are saturated with hydrogen atoms. The central advantage over other approaches is the ability to choose the shape and size of the templating planes, with the possibility to use experimental input.The method is validated on single sheets with a protrusion and application examples are shown for stacked graphitic layers with up to 100 Å size and more than 20000 atoms. It represents the first step of a longer term project. In the future, heteroatoms and functional groups will be implemented, and by combining several such stacks, the approach will allow the construction of more realistic char models using the data from HRTEM images as an experimental boundary condition. On this basis important questions like the adsorption and diffusion of volatiles under high temperatures can be studied on a molecular level.

Tuning MgCl2 content in BMIMPF6 to optimize mg-ion battery performance

This study aims to explore magnesium chloride salt-ionic liquid as an efficient electrolyte for Magnesium-ion Batteries (MIBs) using graphite as a cathode material. A complete physicochemical and electrochemical characterizations were performed on a number of electrolyte compositions and important properties including ion solvation, specific conductivity, ion transport behaviour, dominant ionic species, and electrochemical stability were tested. Also, the effect of magnesium salt concentration on specific capacity, reversibility, stability, charge retention, and rate capability were examined. Moreover, the effect of graphite electrodes on Solid Electrolyte Interphase (SEI) layer, its practicality, and cyclability of the different electrolyte compositions afforded interesting conclusions by this comprehensive comparison of electrode-electrolyte pairings. This evaluation is further supported by life cycle analysis, which gave an important information on how to keep electrodes structurally intact even after several uses. Though there were differences in the three electrolyte systems with respect to reversibility, stability, cyclicbility, capacity fading, and unexpected failures, the 0.2 M electrolyte showcased a notable feature of a high ionic conductivity (4.6 × 10−3 mS cm−1) at room temperature and strong anodic stability (4.0 V vs. Mg/Mg2+). Thus, endorsing the developed system as promising lead for further exploration. Additionally, magnesium dissolution and deposition on a Pt working electrode in this electrolyte was also thoroughly examined in this study. The process of PF6¯ ion intercalation and de-intercalation into graphite layer structure was examined using Cyclic Voltammetry (CV). Based on the analysis by Field Emission- Scanning Electron Microscopy (FE-SEM), Energy Dispersive Spectroscopy (EDS), and X-ray Photoelectron Spectroscopy (XPS), a change in the active-material morphology was observed and we hypothesize that this might be the reason for the improved performance.

Shear-promoted graphite-to-diamond phase transition at the grain boundary of nanocrystalline graphite

High pressure has traditionally been considered essential for the transformation of graphite into diamond. However, reducing the transition pressure required for this graphite-to-diamond (G2D) conversion holds significant appeal in both scientific research and engineering applications. In this study, we conducted large-scale molecular dynamics (MD) simulations using an environment-dependent interaction potential (EDIP) to examine the shear deformation of nanocrystalline graphite (n-graphite) with a grain size of approximately 6.5 nm. We discovered that the G2D transition pressure in n-graphite can be reduced to 2–3 GPa, significantly lower than the ∼90 GPa uniaxial stress required in crystalline graphite. This reduction is primarily due to concentrated local shear stresses at grain boundaries (GBs), which induce substantial rotations of graphite layers. These rotations facilitate the initial formation of diamond bonds at sites of pre-existing imperfections at the GBs, assisted by shear. Once initiated at the GBs, the G2D transition rapidly propagates within grains aligned parallel to the shear components, resulting in the formation of nanocrystalline diamond. Our findings underscore the critical roles of GBs and shear stress in enabling the G2D transition in n-graphite.

High-efficient acetylene synthesis by selective electrochemical formation of CO2-derived CaC2

Acetylene can be used as feedstock for various chemical products, but its raw material has been a fossil fuel, which poses an environmental challenge. One way to address the challenge is to form CaC2 from CO2, which reacts with water to form acetylene. This study demonstrated the selective formation of CaC2 from CO2 by an electrochemical process in NaCl-KCl-CaCl2-CaO melt at 823 K to produce C2H2 with high current efficiency. The CaC2 was formed through two reactions: the carbon electrodeposition from CO2-derived CO32− (Step 1) and the electrochemical reduction of Ca(II) ion on the carbon (Step 2). These two reactions could be controlled by conducting potentiostatic electrolysis under CO2 and Ar atmospheres, resulting in acetylene synthesis with a maximum current efficiency of 92 %. Each electrochemical reaction agreed with the thermodynamic electrode potential. The electrolysis on carbon electrodes revealed that the higher the crystallinity of carbon, the more selectively CaC2 was formed. The CaC2 formation was induced by the reduction of Ca(II) ions on the basal plane of the graphite layer rather than the edge plane. The unique interfacial phenomenon between high-temperature melt and a carbon electrode surface will contribute to realizing a highly efficient CO2 conversion process to acetylene.

Covalently bridging graphene edges for improving mechanical and electrical properties of fibers

Assembling graphene sheets into macroscopic fibers with graphitic layers uniaxially aligned along the fiber axis is of both fundamental and technological importance. However, the optimal performance of graphene-based fibers has been far lower than what is expected based on the properties of individual graphene. Here we show that both mechanical properties and electrical conductivity of graphene-based fibers can be significantly improved if bridges are created between graphene edges through covalent conjugating aromatic amide bonds. The improved electrical conductivity is likely due to extended electron conjugation over the aromatic amide bridged graphene sheets. The larger sheets also result in improved π-π stacking, which, along with the robust aromatic amide linkage, provides high mechanical strength. In our experiments, graphene edges were bridged using the established wet-spinning technique in the presence of an aromatic amine linker, which selectively reacts to carboxyl groups at the graphene edge sites. This technique is already industrial and can be easily upscaled. Our methodology thus paves the way to the fabrication of high-performance macroscopic graphene fibers under optimal techno-economic and ecological conditions.

Boosting the Electrochemical Performance of Primary and Secondary Lithium Batteries with Mn-Doped All-Fluoride Cathodes.

Transition metal fluorides are potentially high specific energy cathode materials of next-generation lithium batteries, and strategies to address their low conductivity typically involve a large amount of carbon coating, which reduces the specific energy of the electrode. In this study, MnyFe1-yF3@CFx was generated by the all-fluoride strategy, converting most of the carbon in MnyFe1-yF3@C into electrochemical active CFx through a controllable NF3 gas phase fluorination method, while still retaining a tightly bound graphite layer to provide initial conductivity, which greatly improved the energy density of the composite. This synergistic effect of nonfluorinated residual carbon (∼11%) and Mn doping ensures the electrochemical kinetics of the composite. The loading mass of the active substance had been increased to 86%. The theoretical and actual discharge capacity of MnyFe1-yF3@CFx composite was up to 765 mAh g-1 (pure FeF3 is 712 mAh g-1) and 728 mAh g-1, respectively. The discharge capacity at the high-voltage (3.0 V) platform was more than three times higher than that of the non-Mn-doped composite (FeF3@CFx).

Nanometer-scale electron beam shaping with thickness controlled and stacked nanostructured graphite

The generation of small electron probes is the basis for various techniques in which such a probe is scanned across a sample, and special probe shapes like vortices can be desirable, e.g., to gain insight into magnetic properties. Micron-scale phase plates or holographic masks, in combination with demagnifying optics, are usually used for creating such special probe wave functions. Here, we present the fabrication of nanometer-sized phase plates based on thickness-selected and stacked graphite layers as well as an analysis of their performance. First, a spiral phase plate is demonstrated that creates a vortex beam with an orbital angular momentum of 1 and an outer radius of 2.5 nm. Second, a three-level Fresnel lens built from two nanopatterned graphite membranes is presented, which achieves a focal spot with a full width at half maximum of 5.5 nm. Third, an array of electron sieves is demonstrated, each of which creates a focal spot with a radius of 2 nm, and the array is applied as a Shack–Hartmann wavefront detector. These elements allow the generation of few-nanometer sized focused probes or vortices without the need for additional optical elements.

Efficient fabrication of high-quality graphene via alternating-current co-intercalation and microwave-assisted expansion

To facilitate the transformation of inexpensive and abundant graphite resources into two-dimensional graphene materials with promising applications, the development of efficient, cost-effective, and scalable technologies for large-scale production of high-quality graphene is crucial. Here, we propose an effective electrochemical dual-electrode co-intercalation exfoliation strategy. During the process, precise control of the electrochemical intercalation is achieved by adjusting the working bias and alternating current (AC) cycle, while ensuring the ion insertion rate through gradual voltage escalation. Repeated insertion of cations and anions under AC accelerates the graphite exfoliation. Following complete ion inserting, suitable microwave processing was employed to achieve rapid graphite expansion. Ultimately, ultra-sonication in NMP is employed to achieve final exfoliation between graphite layers. The resulting few-layer graphene (2–3 layers) exhibited minimal defects (ID/IG = 0.0405), low oxygen content (C/O = 44.62), high yield (95.3 %), and excellent conductivity (625 S/cm), enabling its potential commercialization and large-scale application. This outcome also serves as a significant reference for the commercial production of environmentally friendly and cost-effective graphene.

P‐54: XAI Models for Efficient Analysis of Temperature and Power Consumption in High‐Brightness Panels and Modules

Predicting temperature and power consumption in panels and modules under high brightness has long been a daunting and time‐intensive task, often requiring over a week of simulation work. Addressing this challenge, our study introduces a novel machine learning framework, bifurcated into panel and module stages, to streamline the data acquisition process. A key innovation in our approach is the use of symbolic regression to overcome the limitations posed by the reliance on real‐world measurements for power consumption and heat generation. Employing SPICE simulations, we estimated the current density within the panel, with subsequent validation through Explainable AI (XAI) analysis. This revealed a significant correlation between current density and panel heat generation. Our research also revisits the traditionally neglected areas outside the panel's center, uncovering their impact on heat generation. The layered complexity in modules, previously a barrier to physical sample creation and measurement, was navigated using simulation. XAI insights demonstrated the crucial roles of graphite and metal layers in heat dissipation, and the drive IC as a primary heat source. This integrated approach of real and computational data in machine learning significantly reduced the analysis timeframe from a week to mere minutes, marking a breakthrough in predictive accuracy and efficiency for high‐brightness scenarios.

Improving electrochemical performance of silicon anode through building “soft-hard” double-layer coating

Silicon is believed to be a critical anode material for approaching the roadmap of lithium-ion batteries due to its high specific capacity. But this aim has been hindered by the quick capacity fading of its electrodes during repeated charge–discharge cycles. In this work, a “soft-hard” double-layer coating has been proposed and carried out on ball-milled silicon particles. It is composed of inside conductive pathway and outside elastic coating, which is achieved by decomposing a conductive graphite layer on the silicon surface and further coating it with a polymer layer. The incorporation of the second elastic coating on the inside carbon coating enables silicon particles strongly interacted with binders, thereby making the electrodes displaying an obviously improved cycling stability. As-obtained double-coated silicon anodes deliver a reversible capacity of 2280 mAh g−1 at the voltage of 0.05–2 V, and maintains over 1763 mAh g−1 after 50 cycles. The double-layer coating does not crack after the repeated cycling, critical for the robust performance of the electrodes. In addition, as-obtained silicon particles are mixed with commercial graphite to make actual anodes for lithium-ion batteries. A capacity of 714 mAh g−1 has been achieved based on the total mass of the electrodes containing 10 wt.% double-coated silicon particles. Compared with traditional carbon coating or polymeric coating, the double-coating electrodes display a much better performance. Therefore, the double-coating strategy can give inspiration for better design and synthesis of silicon anodes, as well as other battery materials.

Ester-based electrolytes for graphite solid electrolyte interface layer stabilization and low-temperature performance in lithium-ion batteries

Ester-based electrolytes for graphite solid electrolyte interface layer stabilization and low-temperature performance in lithium-ion batteries

Graphite foils as potential skin and epithelium dosimeters at therapeutic photon energies

This work builds upon a prior study, examining the dosimetric utility of pencil lead and thin graphitic sheets, focusing upon the measurement of skin doses within the mammographic regime. In recognizing the near soft-tissue equivalence of graphite and the earlier-observed favourable thermoluminescence yield of thin sheets of graphite, this has led to present study of 50 μm thick graphite for parameters typical of external beam fractionated radiotherapy and skin dose evaluations. The graphite layers were annealed and then stacked to form an assembly of 0.5 mm nominal thickness. Using a 6 MV photon beam and delivering doses from 2- to 60 Gy, irradiations were conducted, the assembly first forming a superficial layer to a solid water phantom and subsequently underlying a 1.5 cm bolus, seeking to circumvent the build-up to electronic equilibrium for skin treatments. Investigations were made of several dosimetric properties arising from the thermoluminescence yield of the 50 μm thick graphite slabs, in particular proportionality and sensitivity to dose. The results show excellent sensitivity within the dose range of interest, the thermoluminescence response varying with increasing depth through the stacked graphite layers, obtaining a coefficient of determination of 90%. Acknowledging there to be considerable challenge in accurately matching skin thickness with dose, the graphite sheets have nevertheless shown considerable promise as dosimeters of skin, sensitive in determination of dose from the surface of the graphite through to sub-dermal depth thicknesses.

Flame spray pyrolyzed carbon-encapsulated Au/Fe3O4 nanoaggregates enabled efficient photothermal therapy and magnetic hyperthermia of esophageal cancer cells.

Multifunctional magneto-plasmonic nanoparticles with magnetic hyperthermia and photothermal therapy could kill cancer cells efficiently. Herein, carbon-encapsulated Au/Fe3O4 (Au/Fe3O4@C) was fabricated using an enclosed flame spray pyrolysis. The nanostructures, including an Fe3O4 core (51.9-55.2nm) with a decreasing carbon shell thickness and an Au core (4.68-8.75nm) coated with 2-4 graphite layers, were tailored by tuning the C2H4 content in the reacting gas mixture. Saturation magnetization (33.7-48.2emu/g) and optical absorption were determined. The carbon shell facilitated the dispersion of Au/Fe3O4 and restrained their laser-induced and magnetic field-induced coalescence and growth. Au/Fe3O4@C exhibited excellent magnetic resonance imaging capability (91.4mM-1 s-1) and photothermal performance (65.4°C for 0.8mg/mL Au/Fe3O4@C at a power density of 1.0W/cm2 after 300s near-IR laser irradiation (808nm)). Moreover, the combined application of photothermal and magnetic-heating properties reduced the required intensity of both laser and magnetic field compared to the intensity of separate situations. Our work provides a unique, intriguing approach to preparing multicomponent core/shell nanoaggregates that are promising candidates for esophageal cancer cell therapy.

Improvements in bioactivity, blood compatibility, and wear resistance of thermally sprayed carbon nanotube reinforced hydroxyapatite-based orthopedic implants

Titanium implants often fail due to aseptic loosening and non-hemocompatibility, necessitating costly revision surgeries. This study investigated the wear performance and biocompatibility of high-velocity oxy-fuel (HVOF) sprayed-hydroxyapatite (HA) and HA/alumina-19 wt%/carbon nanotube (CNT)− 1 wt% (HAC1) coatings. The novel heterocoagulation colloidal technique effectively dispersed CNTs, enhancing adhesion strength by ∼120 %, hardness by ∼45 %, and wear resistance by ∼32 % in simulated body fluid (SBF) and 17 % in dry conditions versus HA coatings, attributed to the low coefficient of friction (CoF) (1.16–1.48 times than HA) due to lubrication offered by peeled-off graphite layers from the CNT surface. Additionally, HAC1 implants exhibited superior apatite growth (∼52 % than HA), excellent non-hemolytic behavior (∼0.2 %), and no platelet activation, making it highly promising for orthopedic applications.

Transient Electro‐Graphitization of MOFs Affecting the Crystallization of Ruthenium Nanoclusters for Highly Efficient Hydrogen Evolution

AbstractFine control over the graphitization level of carbonized nanostructures can play a strategic role in tuning the crystallization of supported nanocatalysts, thereby modulating the kinetics of catalysis. However, realizing the synergistic interplay of graphitization‐tunable support and supported catalysts poses a significant challenge. This study proposes a current pulse‐induced ultrafast strategy for developing MOF‐derived graphitic nano‐leaves (GNL) and supported ultrafine ruthenium nanoclusters exhibiting selective crystallization states depending on the tunable graphitization level of GNL. The resulting ultrafine (≈0.7 nm) amorphous‐ruthenium nanoclusters linked with GNL (a‐Ru@GNL500) exhibit state‐of‐the‐art performance in the hydrogen evolution reaction (HER), requiring very low overpotentials of only 23.0 and 285.0 mV to achieve current densities of 10 and 500 mA cm−2, respectively. Furthermore, a‐Ru@GNL500 demonstrates exceptional operational stability for 100 h under high HER currents of 200 and 400 mA cm−2. Density functional theory reveals that the unique electronic structure of a‐Ru and the cooperative effect of cobalt embedded in the graphitic layer lower the occupancy of the antibonding orbital, resulting in an accelerated HER process. Additionally, the unique electronic structure, highly conducting GNL, and efficient bubble release dynamics of super‐aerophobic a‐Ru@GNL500 contribute to reduced overpotentials, particularly at high HER current densities.

Hybrid catalyst‐assisted synthesis of multifunctional carbon derived from Camellia shell for high‐performance sodium‐ion batteries and sodium‐ion hybrid capacitors

AbstractBiomass‐derived carbon as energy storage materials have gradually attracted widespread attention due to their low cost, sustainability, and inherent structural advantages. Herein, hard carbon (H‐1200) and porous carbon (PC‐800) for sodium‐ion batteries (SIBs), sodium‐ion capacitors (SICs) half cells and sodium‐ion hybrid capacitors (SIHCs) have been synthesized from the same biomass precursor of Camellia shells through different treatments. H‐1200 synthesized by directly high‐temperature carbonization possesses a rational graphitic layer structure and plentiful heteroatoms. When applied as anode for SIBs, it exhibits a reversible capacity of 365.5 mAh g–1 at 25 mA g–1 and capacity retention 89.0% after 400 cycles at 200 mA g–1. Additionally, PC‐800 prepared by catalytic carbonization of K2C2O4/CaC2O4 hybrid catalyst has a sophisticated porous structure and a high surface area of 2186.9 m2 g–1. When employed as a cathode for SICs, it delivers a maximum capacity 104.2 mAh g–1 at 100 mA g–1 and 35.0 mAh g–1 at 5 A g–1. Furthermore, the all carbon assembled SIHC (H‐1200||PC‐800) using H‐1200 as anode and PC‐800 as cathode, features a broad output voltage range (0.01 ~ 4.1 V), high energy density of 161.5 Wh kg–1, power density of 12896.1 W kg–1, and superior capacity retention of 90.32% after 10000 cycles at 10 A g–1. This research result provide a new horizon for constructing low‐cost and large‐scale production of biomass derived carbon for energy storage materials.

Leaching kinetics of ash impurities from aphanitic graphite by combining dual-ultrasound and hydrochloric acid–potassium hydrogen fluoride

The hydrochloric acid-fluoride salt is useful for purifying graphite. Ultrasonic-assisted technique can significantly reduce the leaching time and improve the leaching efficiency. Compared with single-frequency, dual-frequency ultrasound has the advantages of high energy efficiency and wide cavitation area. In this study, the combination of a dual-frequency ultrasound-assisted technique and hydrochloric acid–potassium hydrogen fluoride leaching agent was proposed for the leaching of aphanitic graphite to remove impurity minerals. First, the effects of probe-type ultrasonic power, tank-type ultrasonic power, temperature, HCl concentration, ultrasonication time, and KHF2 concentration on the purification efficiency of impurities from aphanitic graphite with the assistance of dual-frequency ultrasound were investigated. It was found that the combination of dual-frequency ultrasound and hydrochloric acid–potassium hydrogen fluoride can reduce the ash content of aphanitic graphite from 13.02 % to 1.02 % with an ash removal rate of 94.17 %. Second, volumetric reaction models and unreacted shrinkage nucleation models were used to fit the kinetics of impurities from aphanitic graphite with dual-frequency ultrasound-assisted HCl-KHF2 leaching. Kinetic analysis shows that the volumetric reaction model with chemical control was better to fit the leaching process. This is consistent with the calculation results of the activation energy of the reaction (Ea = 58.13 kJ/mol). Finally, laser particle size analyzer, X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray fluorescence spectroscopy (XRF), transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDS) were used to analyze the fugacity of impurity minerals during the process of dual-frequency ultrasound-assisted HCl-KHF2 leaching. It was revealed that combining ultrasonic cavitation fragmentation with chloric acid–potassium fluoride generated SiF4 with high solubility, thereby removing silica-bearing impurities more efficiently. The challenges in further reducing ash content from 1.02 % in the leached concentrate of aphanitic graphite could be attributed to the existence of titanium-bearing mineral impurities on the surface of graphite particles and the presence of silica-bearing minerals between graphite carbon layers.

Enhanced electrochemical ozone production via sp2 carbon content optimization in boron doped diamond electrodes using laser micromachining

The role and bonding arrangement of deliberately added sp2 carbon in maximising the current efficiency, output and longevity of boron doped diamond (BDD) electrodes for electrochemical dissolved ozone generation is elucidated. We show, using a zero-gap cell (ZGC) arrangement, how systematically increasing sp2 carbon results in increased ozone concentration and current efficiency. sp2 carbon addition is made using nanosecond pulse laser micromachining which converts BDD to sp2 carbon. Two ZGC geometries are investigated which both incorporate a Nafion membrane sandwiched between two BDD electrodes. Through-holes (perforations) are integrated into either the membrane or the BDD, the latter using laser micromachining which also converts the hole walls to sp2 carbon. Increasing the number of through-holes (or changing hole geometry), in the perforated BDD, increases the sp2 carbon content of the electrode (from 5 to 100 %). For the perforated Nafion membrane in contact with a planar BDD electrode, patterned laser micromachining of the BDD surface is used to control the sp2 carbon content of the electrode (from 4 to 100 %). For both electrodes, sp2 carbon content is significantly higher than is possible using diamond growth. sp2 carbon contents >40 % and >60 % for the planar and perforated BDD electrodes, respectively, are found to be particularly effective, allowing electrode designs to be proposed for optimised ZGC ozone generation. Notably, the sp2 carbon introduced via laser micromachining is shown to be extremely stable over 20 h (anode potential ∼ 10 V) in contrast to glassy carbon, which corrodes within 10 min. Whilst both are 100 % sp2 carbon, the laser-machined surface (after ozonolysis) is amorphous whereas the glassy carbon contains disorganized graphitic layers. This work also highlights the intriguing stability of amorphous sp2 carbon towards high oxidative potentials.