Increase In Capacitance Research Articles

Accurate Evaluation of Electro-Thermal Performance in Silicon Nanosheet Field-Effect Transistors with Schemes for Controlling Parasitic Bottom Transistors.

The electro-thermal performance of silicon nanosheet field-effect transistors (NSFETs) with various parasitic bottom transistor (trpbt)-controlling schemes is evaluated. Conventional punch-through stopper, trench inner-spacer (TIS), and bottom oxide (BOX) schemes were investigated from single-device to circuit-level evaluations to avoid overestimating heat's impact on performance. For single-device evaluations, the TIS scheme maintains the device temperature 59.6 and 50.4 K lower than the BOX scheme for n/pFETs, respectively, due to the low thermal conductivity of BOX. However, when the over-etched S/D recess depth (TSD) exceeds 2 nm in the TIS scheme, the RC delay becomes larger than that of the BOX scheme due to increased gate capacitance (Cgg) as the TSD increases. A higher TIS height prevents the Cgg increase and exhibits the best electro-thermal performance at single-device operation. Circuit-level evaluations are conducted with ring oscillators using 3D mixed-mode simulation. Although TIS and BOX schemes have similar oscillation frequencies, the TIS scheme has a slightly lower device temperature. This thermal superiority of the TIS scheme becomes more pronounced as the load capacitance (CL) increases. As CL increases from 1 to 10 fF, the temperature difference between TIS and BOX schemes widens from 1.5 to 4.8 K. Therefore, the TIS scheme is most suitable for controlling trpbt and improving electro-thermal performance in sub-3 nm node NSFETs.

Using anodic oxidation for boosting supercapacitive performance of thermally-oxidized cobalt coatings with various morphologies

Metal oxide electrodes for supercapacitors are commonly synthesized through the hydrothermal method. Despite the simplicity and cost-effectiveness of electrodeposition for producing electrode materials, there is a scarcity of literature on electrodeposited electrodes. Previous studies have utilized nitrate-based solutions and subsequent heat-treatment to fabricate these materials without additional treatments to enhance their performance. This research explores the creation of cobalt coatings with varying morphologies (pyramidal, ridge-shaped, powdery, and rough nodular) using electrodeposition from sulfate-based solutions by adjusting deposition parameters. The cobalt coatings were then heat-treated at 550˚C for 3 h to convert them to cobalt oxide, a promising material for supercapacitor electrodes. The study investigates the impact of initial morphology on the structure, phases formed, and supercapacitive properties of the heat-treated coatings. Analysis of XRD and FTIR data indicated that the primary phase post-heat treatment was Co3O4, alongside some CoO. Cyclic voltammetry (CV) measurements in 1 M KOH solution revealed that the powdery coating exhibited the highest specific capacitance of 796±21 mF cm−2 (∼110 F g−1) at a scanning rate of 2 mV s−1, surpassing the heat-treated pyramidal coating by approximately tenfold. These CV findings were corroborated by galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) analyses. Furthermore, the heat-treated coatings underwent anodic oxidation in a 3 M KCl solution for 5 minutes to assess the impact of this lesser-known process on their capacitive behavior. Following anodic oxidation, the ridge-shaped and pyramidal coatings displayed significantly enhanced specific capacitance due to the formation of fine pores and surface modifications. Specifically, the specific capacitance of the ridge-shaped coating surged from 103±4 mF cm−2 (∼11 F g−1) to 1832±64 mF cm−2 (∼201 F g−1) at a scanning rate of 2 mV s−1 after anodic oxidation. Although the rough nodular coating also experienced an increase in specific capacitance, the morphology and electrochemical characteristics of the powdery coating remained relatively stable throughout the study.

Capacitance-based structural self-sensing of stress: effect of water/cement

The compressive stress self-sensing properties of mortars with different water-cement ratios are investigated without the need for any conductive additives. Mortar specimens are cyclically loaded and the corresponding capacitance and resistance are measured. The aluminum foil that is used as the electrode is wrapped around the prismatic sample. A coplanar configuration of electrodes is used. Capacitance and resistance increase with increasing water/cement (W/C) ratio. Stress causes decrease in capacitance and increase in resistance. The relationship between stress and fractional capacitance-resistance (except for the sample with 0.30 W C−1 ratio) change is reasonably consistent. The effectiveness of stress sensing (the fractional change in capacitance-resistance per unit of stress) decreases monotonically as the maximum stress increases, regardless of the W/C ratio. It is found that the dependence of the effectiveness of the stress sensing on the W/C ratio decreases with an increase in the maximum stress.

Enhanced Spectroscopic Insight into Acceptor-Modified Barium Strontium Titanate Thin Films Deposited via the Sol-Gel Method.

In the present paper, composite thin films of barium strontium titanate (BaxSr1-xTiO3) with an acceptor modifier (magnesium oxide-MgO) were deposited on metal substrates (stainless steel type) using the sol-gel method. The composite thin films feature BaxSr1-xTiO3 ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment at 650 °C, the films were analyzed for their impedance response. Experimental impedance spectra were modeled using the Kohlrausch-Williams-Watts function, revealing stretching parameters (β) in the range of approximately 0.78 to 0.89 and 0.56 to 0.90 for impedance and electric modulus formalisms, respectively. Notably, films modified with 3 mol% MgO exhibited the least stretched relaxation function. Employing the electric equivalent circuit method for data analysis, the "circle fit" analysis demonstrated an increase in capacitance from 2.97 × 10-12 F to 5.78 × 10-10 F with the incorporation of 3 mol% MgO into BST-based thin films. Further analysis based on Voigt, Maxwell, and ladder circuits revealed trends in resistance and capacitance components with varying MgO contents, suggesting non-Debye-type relaxation phenomena across all tested samples.

Enhancing electrochemical hydrogen evolution efficiency via UV ozone treatment: 3D electrode carbon cloths with defect-enriched MoS2

Electrochemical water splitting, a key process for extracting hydrogen energy from water, is recognized as a promising eco-friendly technology. Molybdenum disulfide (MoS2), especially when possessing abundant defects, emerges as a cost-effective and efficient catalyst for hydrogen evolution reaction (HER), presenting a viable alternative to noble metals such as platinum (Pt). However, the impact of UV-Ozone (UVO) in generating defects in bulk 2H-MoS2 remains underexplored. Here, we successfully synthesized 2H-MoS2 using the hydrothermal method on a 3D conductive carbon cloth. Subsequently, the sample underwent UVO treatment for three different durations of 10, 30, and 50 min. Our results demonstrate that a 50-minute exposure to UVO yields the most effective HER performance, with a significant decrease in the onset potential from 189 mV to 116 mV and a low Tafel slope of 64 mV/decade. This enhancement is attributed to increased surface activity, evident in a more than fourfold increase in double-layer capacitance (Cdl). Importantly, the 50-minute UVO treatment not only significantly improves the purity of MoS2 and increases the number of edge sites, but also lead to an increase in sulfur vacancies and the formation of amorphous oxygen-incorporated MoSx. These edge sites, along with sulfur vacancies and oxygens incorporation, are considered ideal for hydrogen binding, enhancing electron transport, and improving HER activity.

Construction of Monolayer Ti3C2Tx MXene on Nickel Foam under High Electrostatic Fields for High-Performance Supercapacitors

Ti3C2Tx MXene, as a common two-dimensional material, has a wide range of applications in electrochemical energy storage. However, the surface forces of few-layer or monolayer Ti3C2Tx MXene lead to easy agglomeration, which hinders the demonstration of its performance due to the characteristics of layered materials. Herein, we report a facile method for preparing monolayer Ti3C2Tx MXene on nickel foam to achieve a self-supporting structure for supercapacitor electrodes under high electrostatic fields. Moreover, the specific capacitance varies with the deposition of different-concentration monolayer Ti3C2Tx MXene on nickel foam. As a result, Ti3C2Tx/NF has a high specific capacitance of 319 mF cm−2 at 2 mA cm−2 and an excellent long-term cycling stability of 94.4% after 7000 cycles. It was observed that the areal specific capacitance increases, whereas the mass specific capacitance decreases with the increasing loading mass. Attributable to the effect of the high electrostatic field, the self-supporting structure of the Ti3C2Tx/NF becomes denser as the concentration of the monolayer Ti3C2Tx MXene ink increases, ultimately affecting its electrochemical performance. This work provides a simple way to overcome the agglomeration problem of few-layer or monolayer MXene, then form a self-supporting electrode exhibiting excellent electrochemical performance.

Preparation of composite based on MXene-Ti3C2 and coconutshell-derived activated carbon for desalination of brackish water

Abstract MXenes is a new two-dimensional material which is gaining more attention in recent years for applications in catalysis, energy storage, and environmental remediation. In this study, MXene-Ti3C2 is synthesized from precursor MAX-Ti3AlC2 via etching method and then combined with coconutshell-derived activated carbon to provide a highly conductive and porous composite. The composite will be later employed as electrode materials in capacitive deionization for water desalination. The results have shown an increase in specific capacitance by 3.7 times in the composite (0.5 wt% MXene-Ti3C2) when compared with pure activated carbon. These promising results have proved the possibility to use MXenes-based composites for desalination and other treatment techniques for salted water.

Enhanced Supercapacitive Performance in Catalyst‐Free Binary Composite SnO2–RuO2 Nanostructured Thin Films for Symmetric Supercapacitor Device

In the present work, thin film electrodes of ruthenium oxide (RuO2), tin oxide (SnO2), and their composite SnO2–RuO2 are deposited on 304 stainless steel substrates using pulsed laser deposition (PLD). These nanostructured electrodes are then evaluated for their suitability in electrochemical energy storage applications. A symmetric supercapacitor device (SSD) is constructed using the SnO2–RuO2 composite electrodes. Compared to individual SnO2 and RuO2 electrodes, the composite electrodes exhibit enhanced specific capacitance and cycle life. This improvement is attributed to modifications in surface morphology and electronic properties. This modified surface morphology of the composite electrode, creates favourable conditions for electrolyte interaction and ion transport, ultimately contributing to the observed increase in specific capacitance. Specifically, the composite electrode demonstrates a specific capacitance of 170.2 Fg−1 at a current density of 0.1 mA cm−2, outperforming SnO2 (37.4 Fg−1). The SnO2–RuO2//SnO2–RuO2 SSD exhibites a specific capacitance of 70.0 Fg−1 at a current density of 0.1 mA cm−2, coupled with energy density and power density values of 19.05 Wh kg−1 and 645 W kg−1, respectively, within a voltage window of 1.4 V. The SSD displays an impressive capacitive retention of 81.27% over 10 000 cycles, indicating its potential for practical energy storage applications.

Electrosorption approach removing PFOA from wastewater using a MXene-polyaniline film

Perfluorooctanoic acid (PFOA) is a persistent organic pollutant found in various industrial effluents, posing significant environmental and health risks. Electrosorption of PFOA on MXene-polyaniline film from water was studied. The results of electrosorption kinetics showed that the functionalized MXene film with polyaniline resulting in an approximately 100 % increase in electrosorption capacitance for PFOA due to increasing of the MXene film's volumetric capacitance and modifying of surface chemistry of MXene. The maximum adsorption of PFOA on MXene and MXene-polyaniline films were 358.5 mg/g and 966.1 mg/g, respectively, at an initial concentration of 100 mg/L upon application of +1.0 V. Moreover, humic acid (HA) competing with the adsorption sites, sodium chloride through the double-layer compression effect, and pH affecting the amine or amide functional groups on MXene-polyaniline which inhibited PFOA adsorption onto MXene-polyaniline film were thoroughly examined. Lastly, the reversible adsorption–desorption cycles show that the MXene–polyaniline film possesses the potential to be used continuously. To address PFAS pollution in water sources, we think our approach can help build effective and long-lasting technology.

Green Plasma Enhanced Synthesis of Multi-Phase NiMnO3 Cathode for Aqueous Zn-Ion Batteries

Rechargeable Zn-ion batteries have the potential to address the need for cheap and widely accessible energy storage. Metal-doped manganese oxide cathodes are a common and effective choice for Zn-ion batteries. Zn-ion battery development can be advanced by overcoming the poor cycle life that many metal-doped Mn-oxide cathodes suffer from. Plasma-treated water (PAW) is created using low input power of 0.145 kWh per liter of PAW and is used to accelerate the reduction and precipitation of MnO4 − and nickel acetate (Ni(Ac)) to form a multiphase NiMnO3 electrode with Ni2+ and Ni3+ doped into the MnO6 octahedra, which exhibits capacitance dominated charge storage mechanisms. The electrode shows initial specific capacitance of 60.1 F g−1 and a capacitance retention of 100.8% after 10,000 cycles and 92.2% after 12,000 cycles. The beneficial layer of nanoflake morphology is formed during cycling, which causes a rapid increase in specific capacitance due to the larger electrochemically active surface area and the associated surface adsorption-based (pseudo-capacitive) type charge storage. We also demonstrate the capability of our multiphase NiMnO3 electrode to be coupled with a Zn metal anode in a battery cell which exhibits 330 mAh g−1 peak specific capacity and capacity retention of 63.8% after 380 cycles.

NON-INVASIVE ASSESSMENT OF HEMODYNAMIC FORCES AND PRESSURE-VOLUME RELATION ANALYSIS IN TWIN PREGNANCY

Objective: This aim of the study was to prospectively investigate pattern of intraventricular Hemo-Dynamic Forces (HDF) associated with Left Ventricular (LV) function and remodeling in women with uncomplicated twin pregnancy. Design and method: Prospective, cohort study. Transthoracic echocardiography was performed on 35 women (aged 35.9±4.7 years) during gestation (<14 w, T1; 14–27 w, T2; >28 w, T3), and 6–7 months after delivery (T0). LV HDF were computed from echocardiography long axis data sets using a novel technique based on endocardial boundary tracking, both in apex-base (A-B) and latero-septal (L-S) directions. HDF distribution was evaluated by L-S over A-B HDF ratio (L-S/A-B HDF ratio). Results: At T1, L-S/A-B HDF ratio was higher than in T0 (p<0.05) indicating HDF misalignment. At T2, a slight impairment of cardiac function was then recorded with a reduction of Global Longitudinal Strain (GLS) and left ventricular End-Systolic Elastance (Ees) at pressure-volume relationship analysis versus T1 (both p<0.05). Finally, at T3, when HDF misalignment and LV contractility reduction (GLS and Ees) were all restored, a rightward shift of the End Diastolic Pressure-Volume Relationship (EDPVR) with an increase of ventricular capacitance were documented. Conclusions: In twin pregnancy, HDF misalignment in the first trimester precedes the slight temporary decrease in left ventricular systolic function in the second trimester; at the third trimester a rightward shift of the EDPVR was associated with a realignment of HDF and normalization of ventricular contractility indexes. These coordinated changes that occur in the maternal heart during twin pregnancy suggests the role of HDF in cardiac remodelling.

Enhancing the specific capacitance of α-MnO2 through quenching-induced changes in the crystal phase structure

The development of materials with high electrochemical performance as response to the energy demand leads to the development of methods for enhancing the specific capacity of energy storage devices, such as heat treatment, which is used to modify the structure and electrochemical performance of materials. This paper reports the enhancement of specific capacitance of α-MnO2 through the high-volume cell (HVC) induced by the quenching technique. Analysis of the transformation and structure of HVC was carried out by a combination of thermal gravimetric analysis and differential scanning calorimetry (TGA–DSC) in addition to X-ray diffraction (XRD), while the characterization of morphology, crystal structure, and capacitance were performed through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and cyclic voltammetry (CV). The α-MnO2 quenched at 437 °C promotes a structural modification that enables an increase in cell volume of 10.6% and an increase in specific capacitance of 20%. The quenching technique would be an attractive methodology to improve the electrochemical performance of materials for energy storage.

Analyzing and mitigating parasitic capacitances in planar transformers for high-frequency operation

Planar magnetic components are compact and less susceptible to skin effect due to their thin copper layers. However, the increase in parasitic capacitance has been a challenge in high-frequency operation of planar transformers (PTs). Parasitic capacitances resonate with inductance and may damage switch devices. Thicker printed circuit board (PCB) and reconfigured windings are suggested in this paper to mitigate the parasitic capacitances. A detailed analysis of the parasitic capacitances is performed with a prototype PT. The resonant frequency increased from 1.27 to 1.63 MHz with a 0.4 mm thicker PCB. The reconfigured PT was 1.38 MHz, 0.3 MHz higher than the original PT.

A unique choline nitrate-based organo-aqueous electrolyte enables carbon/carbon supercapacitor operation in a wide temperature window (-40°C to 60°C).

Some drawbacks of aqueous electrolytes, such as freezing at low temperatures and extensive evaporation at high temperatures, restrict their industrial viability. This article introduces a stabilized neutral aqueous choline nitrate electrolyte with a 10 vol.% methanol additive that improves the temperature stability of the electrolyte via enhanced hydrogen bonding with the choline cation and water and maintains the good state of health of the supercapacitor cells under extreme operating conditions. The symmetric carbon/carbon supercapacitor in 5mol/kg choline nitrate + 10 vol.% methanol (σ = 76ms/cm at 25°C) exhibits 103F/g at room temperature during galvanostatic charge/discharge up to 1.5V, which decreases to 78F/g at -40°C due to the suppressed Faradaic reactions occurring at the carbon electrode. However, under similar charge/discharge conditions, the capacitance increases to 112F/g when the supercapacitor operates at 60°C. This capacitance increase at high temperatures is due to the Faradaic reactions related to enhanced hydrogen adsorption and desorption. The most remarkable aspect of the proposed supercapacitor is its ability to maintain capacitance and power performance during high voltage floating at 1.5V at three tested temperatures (-40°C, 24°C, and 60°C).

Impact of typology and density of point defects on capacitance of graphene-based electrodes

The influence of defects on graphene quantum capacitance has been widely studied using various modeling approaches and in particular the fixed-band approximation (FBA). However, computational models do not yield results in agreement with experiments and can rarely account for the effect of the metallic substrate. They typically predict capacitance values an order of magnitude higher than experiment. In this paper we assess the capacity of the recently developed interfacial capacitance model (ICM) based on density functional theory (DFT) calculations, to investigate the impact of three point-like defects on graphene capacitance. The modeled defects are single-vacancy, double-vacancy, and Stone-Wales; all defective graphene structures are modeled on Cu(111) substrate. The impact of the density of single-vacancy defects on the capacitance was carefully analyzed. The computations demonstrate that the ICM can predict capacitance of graphene on a metallic substrate in agreement with experiment even in the case of the existence of defect. This suggests that ICM can be generalized for assessing graphene capacitance and interfacial capacitance regardless of morphology of the surface. The results ranged from 1.692 μF cm−2 to 1.872 μF cm−2 for defective models, compared with 1.73 μF cm−2 of pristine model which is in agreement with experiment. Various defective cases were analyzed using density of states, projected density of states, electrons isosurfaces, and structural parameters. The charge separation triggered by defects can be correlated with the increase in capacitance as long as no chemical bonding is triggered by the defect between copper and graphene.

Near‐Infrared Active Tri‐nanohybrid for Enhanced Energy Harvesting

AbstractEfficient energy harvesting through full solar spectrum utilization has been considered a promising solution to world energy and environmental issues. In this direction, lead sulphide (PbS) quantum dot (QD) based hybrid materials find greater application due to their near‐infrared (NIR) active photo response. Slower charge injection and inefficient charge separation limit photoactive response of such NIR active low band gap semiconductor like PbS QDs. Moreover, constructing dual charge transfer pathways in a PbS QDs based nanocomposite through the formation of hybrids with suitable materials can be advantageous in suppressing the charge recombination. In this work, we have synthesized a nanocomposite after decorating the PbS‐QDs with semiconducting TiO2 nanoparticles modified with multiwall carbon nanotubes (MWCNT) and thus forming the tri‐hybrid (PbS‐TiO2‐MWCNT) nanocomposites. The enhanced photo‐activities of the tri‐hybrid, as compared to di‐hybrids like PbS‐TiO2, PbS‐MWCNT were confirmed by the steady state, time‐resolved photoluminescence (TRPL) measurements and reactive oxygen species (ROS) generation measurements. Higher ROS generation in the tri‐hybrid has been correlated with a faster interfacial electron transfer due to the dual charge injection pathway of PbS QD to TiO2 and MWCNT. The enhanced activity of the trio‐hybrid has also been analyzed from the first principal calculations in light of an efficient interfacial electron transfer as a result of the dual charge injection pathway. The photoelectrochemical water‐spilling response of the photoanodes in terms of photocurrent density, electrochemical impedance, and Mott–Schottky measurements on PbS‐TiO2 and PbS‐TiO2‐MWCNT photoanodes reveal that a combination of MWCNT and TiO2 exhibits an increase in electrical double layer capacitance, decrease in series resistance and enhancement of carrier density with NIR illumination at the heterojunction. Overall, all the dynamical studies at the interface of the trihybrid‐based photoanodes demonstrate its potential of utilization as a futuristic NIR‐ active photoelectrochemical water‐splitting material.

Pencil drawn interdigitated capacitive sensors on wood substrate

This research presents the fabrication and characterization of an interdigitated capacitive (IDC) sensor on a wooden substrate using pencil traces. The resistance of the pencil traces decreased from 100 kΩ to 5 kΩ as the pencil grade shifted from HB to 8B. Concurrently, capacitance measurements revealed an increase from approximately 5 pF for a 5-finger IDC made with HB pencil to around 32 pF for an 8B pencil counterpart. Increasing the number of pencil traces from 10 to 50 resulted in a significant decrease in resistance and a proportional increase in capacitance. Application of the IDC sensor demonstrated notable changes in capacitance upon proximity and touch, with a significant decrease upon removal. The interdigitated capacitance sensor exhibits good proximity effects and contact sensitivity in touch, with capacitance increasing exponentially from 0.3 pF (7 cm) to 1.2 pF (direct contact), highlighting its ability to detect objects with high precision. Additionally, environmental factors such as temperature and humidity influence capacitance values. These findings underscore the potential of pencil-drawn IDC sensors for responsive and adaptable applications in various fields.

Effect of Ultra‐Thin AlGaN Regrown Layer on the Electrical Properties of ZrO2/AlGaN/GaN Structures

Effects of the ultrathin 1 nm thick AlGaN regrown layer before gate insulator deposition on the performance of ZrO2/AlGaN/GaN metal‐insulator‐semiconductor (MIS) structures are investigated. In comparison with the reference ZrO2/AlGaN/GaN MIS high‐electron‐mobility transistors (MIS‐HEMTs), MIS‐HEMTs with AlGaN regrown layer exhibit increased maximum drain current (>1050 mA mm−1) and broader full‐width at half maximum (FWHM) of transconductance profile (11 V). Moreover, the gate leakage current in the forward direction is reduced by about four orders of magnitude while the hysteresis of the transfer curves is cut‐down to more than 40%. Compared with the control MIS‐capacitors (MIS‐caps), MIS‐caps with regrowth show highly evident sudden increase in capacitance known as “spill‐over” in the capacitance–voltage (C–V) profiles, suggesting improved ZrO2/AlGaN interfaces. Extracted electron states from the C–V profiles, reveal 6 times to 14 times reduction of interface states density within 0.2 to 0.8 eV from the AlGaN conduction band edge. Using photo‐assisted C–V measurements, the near mid‐gap electron states density of MIS‐caps is extracted with regrowth to be at least three times less than those of reference MIS‐caps. Findings in this work are very similar to those recently reported Al2O3/regrown‐AlGaN interfaces, suggesting that the regrowth technique could be universal in reducing electron states along insulator/AlGaN interfaces.

Machining behavior of Al7075-B4C-MoS2 composites with different flushing medium

ABSTRACT Using hydrocarbon oils as a flushing medium causes lots of issues to machinists such as cancer. In this study, the behavior of green flushing medium (SF biodiesel and deionized water) during µED milling of hybrid metal matrix composites (HMMC) under various parametric settings of reinforcement wt%, capacitance and feed rate is analyzed. Metal erosion rate (MER) decreases with rise in capacitance due to longer interval between sparks. Higher MER is attained with lower order wt % reinforcement whereas the surface roughness increases increment in wt % reinforcement. S vk and Sk rise exponentially with increase in capacitance for considered green flushing medium. Kerosene offered higher MER compared to deionized water and Sunflower BD at considered machining condition. RLT appears to be more with DI water compared Sunflower BD due to deposition of debris on the surface. S vk and Sk is found be minimum with SF biodiesel at considered parametric settings.

Large-Area Fabrication of Porous Graphene Networks on Carbon Fabric via Millisecond Photothermal Processing of Polyaniline for Supercapacitors.

Supercapacitors demonstrate promising potential for flexible, multi-functional energy storage devices; however, their widespread adoption is confronted by fabrication challenges. To access a combination of desirable device qualities such as flexibility, lightweight, structural stability, and enhanced electrochemical performance, carbon fiber (CF) can be utilized as a current collector, alongside graphene as an electrochemically active material. Yet achieving a cost-effective, large-scale graphene production, particularly on CF, remains challenging. Here, a rapid (<1min) photothermal approach is developed for the large-scale production of graphene directly onto CF, utilizing polyaniline (PANI) as a polymer precursor. The in situ electropolymerization of PANI on CF facilitates its rapid synthesis on large areas, followed by conversion into graphene networks, enabling the binder-free fabrication of supercapacitor devices. These devices exhibit an areal capacitance of 180mFcm-2 (at 2mAcm-2 in 1mH2SO4), an order of magnitude higher than other fabric-based devices. Moreover, the devised photothermal strategy allows for one-step preparation of supercapacitor devices on areas exceeding 100cm-2, yielding an absolute areal capacitance of 4.5F. The proportional increase in capacitance with device area facilitates scaling and indicates the commercial viability of this approach for low-cost, energy-efficient, and high-throughput production of lightweight, high-performance graphene-based multi-functional supercapacitor devices.