Quick Charging Research Articles

Visible-light-responsive mesoporous PtO/2D YVO4 composite material for fostered photocatalytic hydrogen generation

Hydrogen (H2) is a significant alternative energy supply due to its outstanding and potentially useful properties, promoting sustainable development. Photocatalytic H2 generation from H2O employing inexhaustible and naturally abundant solar power on semiconducting photocatalysts is a promising and sustainable approach. Yet, particle aggregation/agglomeration, insufficient solar-light absorbance capacity, and quick photo-excited charge carriers’ recombination are the main deficiencies in most current photocatalytic systems. This investigation intends to fabricate mesoporous YVO4 nanosheets through a facile hydrothermal process, employing polyvinyl alcohol polymer as a structural directing agent to prevent agglomeration. Moreover, for the first time, varied tiny contents of platinum oxide (PtO) ranging from 0.3 to 1.2 wt%, were decorated on YVO4, constructing p-n PtO-YVO4 heterojunctions. The fabricated catalysts were characterized via advanced instruments and applied to H2 production using visible light energy. It was found that the physicochemical characteristics of the designed catalysts revealed the influence of loading PtO on the surface, structure, light absorbance features, charge separation, and efficacy. The loading of 0.9 wt% PtO on YVO4 has barely lowered the surface area (SA) from 187 to 176 m2/g. In contrast, the visible wavelength uptake is notably extended owing to the substantial energy bandgap narrowing from 3.40 to 2.11 eV. The visible-light-evolved hydrogen on 0.9 wt% PtO-YVO4 amounted to 34.76 mmol g−1. Moreover, this novel sample demonstrated a 99.88% recycling capacity after five cycles. This efficacious photocatalytic H2 generation is due to extensive light sensitivity and the rapid charge separation and migration between PtO and YVO4 following the p-n heterojunction mechanism.

High‐performance symmetric supercapacitor using cost‐efficient iron oxide (Fe3O4) nanoparticles

AbstractWe investigated Fe3O4 nanoparticles (NPs) for a symmetric supercapacitor (SSC) under ambient conditions from synthesizing material to device fabrication. The prepared Fe3O4 NPs are characterized using different characterization, X‐ray diffraction, Raman and FTIR spectroscopy. The electrochemical performance of supercapacitor (SC) is measured in two electrode systems using coin‐cell assembly at various scan rates varying from 10–100 mV s−1, and cyclic voltammetry measurements are investigated from −0.8 to 0.6 V window. The Fe3O4 NPs based SSC shows an energy density of 24.99 Wh kg−1 with the high specific capacitance of 91.82 F g−1 at 10 mV s−1 scan rate. At a current rate of 4 A g−1, the power density reaches 2000 W kg−1. The Fe3O4 NPs based SSC exhibits a quick charge and discharge mechanism at various current rates and is stable over 500 galvanostatic chargingdischarging cycles at a current rate of 4 A g−1. The fabricated SSC showed >60% capacitance retention even after operating for 1000 cyclic voltammetry cycles at a scan rate of 100 mV s−1. A reasonable choice for SSC electrodes with high power density, and the outstanding resilience of electrodes is further shown by cyclic stability and impedance study exhibiting a negligible change in the different impedance elements. The potential of the fabricated SSC is demonstrated by lightening a light emitting diode (LED) light as a practical aspect for future applications.

Advancement in Supercapacitors for IoT Applications by Using Machine Learning: Current Trends and Future Technology

Supercapacitors (SCs) are gaining attention for Internet of Things (IoT) devices because of their impressive characteristics, including their high power and energy density, extended lifespan, significant cycling stability, and quick charge–discharge cycles. Hence, it is essential to make precise predictions about the capacitance and lifespan of supercapacitors to choose the appropriate materials and develop plans for replacement. Carbon-based supercapacitor electrodes are crucial for the advancement of contemporary technology, serving as a key component among numerous types of electrode materials. Moreover, accurately forecasting the lifespan of energy storage devices may greatly improve the efficient handling of system malfunctions. Researchers worldwide have increasingly shown interest in using machine learning (ML) approaches for predicting the performance of energy storage materials. The interest in machine learning is driven by its noteworthy benefits, such as improved accuracy in predictions, time efficiency, and cost-effectiveness. This paper reviews different charge storage processes, categorizes SCs, and investigates frequently employed carbon electrode components. The performance of supercapacitors, which is crucial for Internet of Things (IoT) applications, is affected by a number of their characteristics, including their power density, charge storage capacity, and cycle longevity. Additionally, we provide an in-depth review of several recently developed ML-driven models used for predicting energy substance properties and optimizing supercapacitor effectiveness. The purpose of these proposed ML algorithms is to validate their anticipated accuracies, aid in the selection of models, and highlight future research topics in the field of scientific computing. Overall, this research highlights the possibility of using ML techniques to make significant advancements in the field of energy-storing device development.

Low‐voltage ride‐through control strategy for flywheel energy storage system

AbstractDue to its high energy storage density, high instantaneous power, quick charging and discharging speeds, and high energy conversion efficiency, flywheel energy storage technology has emerged as a new player in the field of novel energy storage. With the wide application of flywheel energy storage system (FESS) in power systems, especially under changing grid conditions, the low‐voltage ride‐through (LVRT) problem has become an important challenge limiting their performance. In this paper, we propose a machine‐grid side coordinated control strategy based on model predictive current control (MPCC) for the insufficient LVRT capability of traditional FESS during grid faults. Excellent dynamic properties are demonstrated by the technique, which allows the grid‐side converter output current to swiftly follow the reference current instruction. The FESS's LVRT capability is increased when the grid‐side converter uses the MPCC current inner loop rather than the proportional–integral current inner loop during grid voltage dips. This greatly increases the reactive power response speed and efficiently supports the quick recovery of grid voltage. According to simulation verification carried out by Matlab/Simulink, the suggested control approach can assure the long‐term dependable operation of the FESS during voltage dips. This study can also be used as a reference for improving the FESS's LVRT capabilities in the future.

Building composite of layered yttrium hydroxide and carbon nanotube as the sulfur host for high-performance lithium‑sulfur batteries

The commercialization of lithium‑sulfur batteries is still confronting with great challenges due to the sluggish redox kinetics of sulfur and the shuttle effect of lithium polysulfides (LiPS). Herein, two-dimensional (2D) layered yttrium hydroxide (LYH) nanosheets are in-situ grown on multiwalled carbon nanotubes (CNTs) and used as a multifunctional host material (LYH@CNT) for sulfur loading. The crosslinked CNTs provide a robust and conductive network for quick charge transfer and sufficient active site exposure, while LYH nanosheets demonstrate strong ability for anchor and catalytic conversion of lithium polysulfides. The theoretical calculation and adsorption experiment also confirm the strong adsorption of LYH for lithium polysulfides. Therefore, sulfur loaded on LYH@CNT exhibits excellent electrochemical performance, such as a good cycling stability with a capacity of 484 mAh g−1 after 800 cycles at 2C. This study opens a new avenue in the development of advanced sulfur hosts for lithium‑sulfur batteries.

Realization of ultracapacitor as sole energy storage device in induction motor drive electric vehicle with modified state timing based field weakening control algorithm

This article employs the concept of realizing an electric vehicle (EV) driven by an induction motor (IM) with an ultracapacitor (UC) as a sole energy storage device for a short distance range in city drive. In battery-driven EVs, the performance of batteries will extensively degrade during frequent start, stop, acceleration and deceleration of the vehicle. However, UC can withstand that circumstance without any degradation. High charge/discharge efficiency, high power density, high temperature withstand capabilities and quick charging capability allows UC to run the EV for an extended range, including the regenerative braking technique. Apart from source, EVs also require efficient drive control for a smooth vehicle operation in the entire driving range. To achieve the vehicle characteristics, it is preferred to operate the propulsion drive in the field weakening (FW) region over the constant torque region. This paper also proposes a Modified State Timing SVPWM Based Control Algorithm for the FW region operation of IM for EV applications. The proposed algorithm is designed to overcome the torque ripple issue of the conventional SVPWM Based Control Algorithm in the FW region. The reduction in torque ripple is achieved by imposing current and voltage limits on the motor d and q axis by considering a maximum modulation index of 1.2732 and with an additional current loop for mitigating the transients in the torque due to sudden variation of the load. The simulation/hardware studies show a smooth operation of UC-driven EV for an entire driving range with a 78.57 percent improvement in torque ripple in the FW region by the proposed algorithm compared with the conventional FW control algorithm. The real time Lab prototype of UC driven EV has been developed and the proposed algorithm has been validated in real-time using the STM32F407VGTx ARM Cortex M4 microcontroller.

Bimetallic NiCo2Se4/Fe2CoSe4 chrysanthemum flowers assembled by nanosheets: An efficient electrode material for hybrid supercapacitor applications

Transition metal selenides have excellent promise for high-performance electrode materials owing to their great electrical conductivity and theoretical capacity. Unfortunately, the electrochemical performance of single-metal selenides is undesirable because of their low energy density and poor cyclic stability, and one practical approach is to introduce heteroatoms to create bimetallic selenides. Herein, a novel bimetallic NiCo2Se4/Fe2CoSe4 chrysanthemum flower assembled by nanosheets on NiF was synthesized via a hydrothermal process as a binder-free electrode for a hybrid supercapacitor. Because of the presence of plentiful redox active sites, unique architecture with large surface area and mesoporous channels, desirable electrical conductivity, and synergistic effect of Ni, Co, and Fe, the bimetallic NiCo2Se4/Fe2CoSe4 electrode material shows significantly increased electrochemical performance. Interestingly, the bimetallic NiCo2Se4/Fe2CoSe4 electrode material shows an outstanding specific capacity of 323.66 mAhg−1 (1175.97 Cg−1) at 1 Ag−1, retaining 91.08% of the initial capacity at 20 Ag−1, with long-lasting cyclic stability of 91.08% after 10,000 GCD cycles at 20 Ag−1. A binder-free bimetallic NiCo2Se4/Fe2CoSe4 @NiF electrode's outstanding electrochemical efficiency can be related to the existence of two bimetallic selenides, and beneficial interaction, which yields quick charge transfer reactions. Moreover, the NiCo2Se4/Fe2CoSe4@NiF//AC@NiF hybrid supercapacitor by bimetallic NiCo2Se4/Fe2CoSe4@NiF (positive electrode) and activated carbon (AC@NiF, negative electrode) displayed specific energy which is 51.83 Whkg−1 at 749.83 Wkg−1 and 34.2 Whkg−1 at 14996.34 Wkg−1 at 20 Ag−1 and superior stability of 92.33% after 10,000 GCD cycles. This research provides some insight into the design of an electrode material with a flower-like decorated with nanosheets morphology for hybrid supercapacitors.

A breakthrough in Coulombic reversibility of dual-ion batteries at quick charge and underlying mechanisms

Dual-ion batteries (DIBs) with renewable graphite as cathode materials have emerged as promising alternatives to Li-ion batteries because of their sustainability and cost-effectiveness. However, DIBs still suffer from the low initial Coulombic efficiency and rapid capacity fading upon long-term cycling due to the intense co-intercalation and oxidative decomposition of electrolytes along with the anions intercalation into graphite at high potentials. To mitigate the electrolyte reactions, the common strategies are mainly focused on the optimization of electrolyte components and surface modification of graphite particles to construct superior cathode/electrolyte interphases (CEI). This work innovatively discovers and reveals that the CEI structure and electrochemical reversibility of Li||graphite DIBs can be optimized through simply adjusting the charge rates. The initial Coulombic efficiency is increased to a very high value of 90.6 % (at the charge rate of 2C), in sharp contrast with the value of 40.8 % (at the charge rate of 0.1C). Besides, the overall electrochemical performances including the reversible capacity, cycling stability and high-rate capability are all improved significantly. These results not only provide an easy strategy for the performance improvement of DIBs but also shed light on the correlation among the charge rates, electrochemical reversibility and CEI of DIBs.

Fabrication of the ternary dual S-scheme ZnO/ZnS/In2S3 heterojunction for enhancing pollutant photodegradation

The construction of heterojunction for photocatalysis has garnered much research interest. Herein, we report the successful fabrication of a ternary dual S-scheme ZnO/ZnS/In2S3 heterojunction with a higher photocatalytic capacity via a hydrothermal method. Specifically, the optimized ternary heterojunction ZSI0.35 sample achieves the 100 % photodegradation efficiency of RhB (10 mg/L, 50 mL) within 10 min, approximately 17 and 8 times higher than pure ZnO and ZnO/ZnS binary heterojunction, respectively. Further characterization results confirm the dual S-scheme heterojunction structure in the fabricated ZnO/ZnS/In2S3 ternary heterojunction, and the improvement of photocatalytic properties can be attributed to the enhanced Brunauer Emmett-Teller (BET) surface area, the improved redox capacity of the photocatalyst, and the quick charge transfer. Additionally, the possible photocatalytic mechanism is discussed according to the measurements. This work provides an efficient strategy of promising heterojunction photocatalysts for photocatalytic environmental remediation.

Developments in conducting polymer-, metal oxide-, and carbon nanotube-based composite electrode materials for supercapacitors: a review.

Supercapacitors are the latest development in the field of energy storage devices (ESDs). A lot of research has been done in the last few decades to increase the performance of supercapacitors. The electrodes of supercapacitors are modified by composite materials based on conducting polymers, metal oxide nanoparticles, metal-organic frameworks, covalent organic frameworks, MXenes, chalcogenides, carbon nanotubes (CNTs), etc. In comparison to rechargeable batteries, supercapacitors have advantages such as quick charging and high power density. This review is focused on the progress in the development of electrode materials for supercapacitors using composite materials based on conducting polymers, graphene, metal oxide nanoparticles/nanofibres, and CNTs. Moreover, we investigated different types of ESDs as well as their electrochemical energy storage mechanisms and kinetic aspects. We have also discussed the classification of different types of SCs; advantages and drawbacks of SCs and other ESDs; and the use of nanofibres, carbon, CNTs, graphene, metal oxide-nanofibres, and conducting polymers as electrode materials for SCs. Furthermore, modifications in the development of different types of SCs such as pseudo-capacitors, hybrid capacitors, and electrical double-layer capacitors are discussed in detail; both electrolyte-based and electrolyte-free supercapacitors are taken into consideration. This review will help in designing and fabricating high-performance supercapacitors with high energy density and power output, which will act as an alternative to Li-ion batteries in the future.

Strategies for electrolyte modification of lithium-ion batteries under low-temperature environments

Because of their high energy density, high voltage platform, extended cycle life, lack of memory effect, low self-discharge rate, environmental friendliness, and quick charging, lithium-ion batteries, or LIBs, are a vital component of contemporary electronic gadgets. Temperature has a complicated and wide-ranging effect on lithium-ion batteries, though. Lithium-ion batteries will have much-reduced performance, particularly in low-temperature conditions. The total performance of batteries is significantly impacted by the quality and performance of electrolytes in China. In particular, the electrolyte’s purpose in lithium-ion batteries is primarily to convey lithium ions; the battery’s ability to function at low temperatures is greatly influenced by the electrolyte’s ion conductivity and SEI film-forming capabilities. Thus, this article begins by providing an overview of the fundamental composition and properties of lithium-ion batteries. The impact of low-temperature circumstances on lithium ion performance was then discussed. Lastly, many modification techniques were suggested from the electrolyte’s point of view to enhance lithium-ion battery performance in low-temperature settings.

Enhancement of quick charging and discharging of tes system by PCM mixed with Al2O3 nano particles for EV

Technology for storing heat energy with small amount of area has been proposed a challenge to the researchers over the past few decades. This would render highly useful for the thermal management system of electric vehicles. The PCM was used as an energy storage system in this work. It offers the chief advantage of higher storage density which is very much expected for both industrial and domestic needs, especially electric vehicles. In this work, the enhancement of specific heat capacity for the provided PCM was improved by embedding alumina nanoparticles into the storage medium. The addition of nanoparticles in the PCM resulted in the increase of heat absorption capacity, a 50% increase in charging time and a 25% reduction in discharging time of the PCM for the volume concentration of 0.833%. The increase of efficiency by 6% during charging and 4% during the discharging processes were observed as the effect of addition of alumina nanoparticle in the system.

Facile Synthesis of Pre-Lithiated LiTiO2 Nanoparticles for Quick Charge and Long Lifespan Anode in Lithium-Ion Batteries.

Titanium dioxide (TiO2) has been widely used as an alternative anodic material for lithium-ion batteries (LIBs) due to its ultrahigh capacity retention and long cycle lifespan. However, the restriction of lithium insertion, intrinsically poor electronic conductivity, and sluggish lithium ionic kinetics of bulk TiO2 hinder their specific capacity and rate performance. Herein, LiTiO2 nanoparticles (NPs) are synthesized via a facile ball milling method by the reaction of anatase TiO2 with LiH. The as-prepared LiTiO2 NPs have strong structural stability and a "zero strain" effect during the repeated intercalation/deintercalation, even at low potential. As anodic materials for LIBs, LiTiO2 NPs exhibit a superior rate performance of ∼100 mA h g-1 at 10C (3350 mA g-1) with a capacity retention of 100% after 1000 cycles, which is 5 times higher than that of the original commercial anatase TiO2 powder. The higher specific capacity of LiTiO2 NPs is attributed to the increased conversion of Ti3+ to Ti2+ on the porous surface of LiTiO2 NPs, which provides a more capacitive contribution. This study not only provides a new fabrication approach toward Ti-based anodes for ultrafast LIBs but also underscores the potential importance of embedding lithium into transition metal oxides as a strategy for boosting their electrochemical performance.

Nanocrystals Conversion Chemistry within Slit-like 2D-Nanogap for High-Rate Cyclic Stability of Lithium-Ion Battery Anodes

A deep understanding of nanocrystal (NC) conversion chemistry is necessary to access alternative synthetic routes for naturally inaccessible nanostructures and fundamental solutions of any interference impeding their practical applications. For durable catalytic processes and practical energy storage devices, this can enable sustaining full reversibility connecting the active NC components under long, harsh operational conditions. Redox convertible late transition metal oxide (TMO) NCs are excellent anode materials for Li-ion batteries (LIBs) with many superior properties but have deviated from the reversible lithiation/delithiation mechanism (MxOy + 2yLi+ + 2e- xM0/yLi2O). Thus, undesired NC-coalescence and irreversible solid-electrolyte-interphase (SEI) formations result in significant capacity loss with repeated charge/discharge cycles and at high cycling rates (>2.0 C). Several methods, involving immobilization on conductive supports, manipulated crystalline phases, and fabricating hierarchical assemblies, have been investigated to resolve this issue. Sheet-like 2D-TMO nanostructures, which electrochemically convert to reduced metal NC-arrays in 2D-geometry, have proven effective at improving reversible and cycling anode performance at moderate current density ranges (0.2 ~ 1.0 C). However, for practical LIB devices, an increased storage performance, especially at quick charging conditions (> 3.0 C), is required, which may be realized through optimizing 2D-TMOs for improved conversion reversibility. However, as the attempted 2D-TMOs have rough thickness uniformity mostly in the 10 ~ 100 nm range long with the lateral size above 250 nm and often fabricated in the carbon-hybrid form, precise interpretation of thickness-dependent effects of 2D-TMO electrodes, especially within a few-nm-thick range, is still unaccomplished. Hence, we attempted fabrication of thinner 2D-TMOs with well-controlled uniform few-nm thicknesses and assess their effectiveness as LIB anodes based on transformation behavior under redox-switching conditions. The confinement of in-situ created NCs inside the few-nm-thin 2D-nanospace, as pre-defined by the thickness of initial 2D-TMO, would hinder free movement, agglomeration, and sintering of included NCs during their phase transition, improving conversion reversibility. The use of atomic-thin 2D-TMOs was envisioned to place single laterally aligned NC arrays at the ultrathin 2D nanogap, ensuring fully reversible interconversion between reactive NC redox-pairs. However, atomic-thin 2D nanosheets of late TMOs, which are intrinsically non-layered materials, remain a synthetic challenge under conventional methods.Herein, we adopted the nanospace confinement strategy to thermally transform delaminated layered double hydroxides (NiCo-LDH) within a 2D-SiO2 envelope, forming isomorphic 2D-TMOs (Ni3Co1Ox, NCOs) of uniform 1 nm and 7 nm thicknesses from LDH precursors. A thermal conversion study of the 2D-TMOs under the 2D-SiO2-shell protection, as well as an electrochemical investigation within the in-situ formed 2D SEI-envelope identified a substantial confinement effect on sustaining the fully cyclic transformation behavior of the derived NC arrays from 1 nm-thin 2D-TMOs. Thus, the atomic-thin 2D-TMO anode demonstrated highly reversible capacity of 848.36 mAh g-1 at the first cycle and a high-rate capability (a specific capacity of 61.2% at 5.0 C relative to 0.2 C) and, the long-term stable Li-ion storage capacity delivered 1169 mAh g-1 and 913 mAh g-1 of specific capacity during 1000 cycles even at rapid charge/discharge conditions of 3.0 C and 5.0 C rates, respectively.

Si[formula omitted]BN nanosheets as anchoring cathode material for realizing high capacity Al-ion battery

Identifying a stable and high-capacity cathode material is crucial for the practical implementation of Aluminium-ion batteries (AIBs). Using first-principles calculations, we propose Si2BN as a suitable cathode material for AIBs. We show that sp2 hybrid Si2BN nanosheets with polar-covalent bonding nature favour the adsorption of a large number of AlCl4 clusters with significant charge transfer that results in a higher adsorption strength and stability compared to non-polar carbon cathodes. The estimated theoretical specific capacity (TSC) of Si2BN is 330 mAh/g, which is six times higher than that of graphite. Bilayer studies reveal that Si2BN shows surface adsorption of AlCl4 similar to that of the monolayer, but intercalation at low concentration of AlCl4 is unfavourable and it also shows that the binding strength of AlCl4 significantly improves when we first adsorb AlCl4 on the outer layers of Si2BN and then intercalate it between the layers. The nudged elastic band (NEB) study elucidates an easy diffusion of AlCl4 along the two-dimensional sheet with a barrier of 0.19−0.22 eV. Thermodynamical stability analysis implies the absence of more serious Cl2 gas evolution that makes Si2BN a durable cathode material. Hence, the proposed Si2BN has a great advantage over carbonaceous cathodes for designing high energy density and quick charge AIBs.

Performance Assessment of Battery Electric Vehicles Using the TOPSIS Method

Worldwide interest in "hybrid and battery electric vehicles" has increased recently as a result of their ability to save on fuel, lessen reliance on foreign oil, and reduce greenhouse gas emissions. The effectiveness of the sub-systems that these vehicles are built with determines their overall success in large part. It is necessary to estimate these subsystems' parameters with great accuracy to improve their performances. "Battery electric vehicles (BEVs)", an eco-friendly type of vehicle, are crucial given that the automotive industry contributes significantly to carbon emissions. Due to the recent quick growth of the BEV market, it has grown to be a substantial challenge to evaluate BEV alternatives fully from the perspective of the consumer. By examining the fundamental characteristics of each BEV, this evaluation can be made. The use of "multiple criteria decision making (MCDM)" techniques is a useful tool for making the best BEV buying choice. Therefore, six BEVs are selected as options in this work. These vehicles are then ranked using TOPSIS based on technical specifications, such as Battery capacity, Range, Top speed, Quick charge time, Acceleration and Purchasing price. In this study TOPSIS method analyses the rank of Mercedes-Benz EQS as first, Audi e-tron GT as fourth, Porsche Taycan as fifth, Audi e-tron as third, Audi RS e-tron GT as second and Mercedes-Benz EQC as sixth. So, the result from the TOPSIS method shows that Mercedes-Benz EQS is highlighted as the best choice of the selected battery electric vehicles followed by the Audi RS e-tron GT.

Elaboration of CuS nanomaterials via hydrothermal route: Examining physical properties and photocatalytic potential

The stable and efficient CuS photocatalyst was elaborated by the facile hydrothermal route at 140 °C for various durations, from copper chloride (CuCl2) and thiourea (SC(NH2)2) aqueous solutions. Characterization techniques such as X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) coupled with energy-dispersive of X-ray system (EDX) analysis, showed the formation of pure CuS nanomaterial. Electrochemical impedance spectroscopy (EIS) revealed that synthesized CuS exhibited a quick charge transfer at high frequencies and a diffusion or transport of ions from the electrolyte to the electrode surface at medium and low frequencies. Hall effect measurement indicated that all prepared CuS are a p-type semiconductors with a hole concentration on the order of 1020 cm−3. A decrease in the hole concentration with increasing heat treatment duration was observed and related to the healing of Cu vacancies. Transmittance and absorbance measurements showed that all samples interacted with light, exhibiting a prominent peak around 600 nm. Tauc method revealed an increase of the optical band gap values from 1.56 to 1.75 eV with the increment of heat treatment duration. Photocatalytic activity of CuS prepared at 140 °C for 16 h was determined by measuring the degradation rate of methylene blue (MB) dye under UV light in the absence and presence of hydrogen peroxide (H2O2). The results demonstrate CuS as a stable and efficient photocatalyst and underscore its potential for application in wastewater purification processes.

Hydrothermal synthesis of ZnO@MoTe2 nanocomposite as excellent electrocatalyst for hydrogen evolution reaction (HER)

The comprehension of novel fundamental inquiries about the design of electrocatalysts is of paramount importance in enhancing the availability of renewable energy resources and advancing the progress of exceptionally durable and effective nonprecious electrocatalysts for the process of water splitting. Enhancing the capacity of renewable energy storage systems through the usage of nonprecious nanocomposites for efficient H2O splitting holds the potential to foster a more sustainable and environmentally conscious society, hence mitigating the impact of global warming. The nanocomposite exhibits proficient catalytic kinetics for the HER process owing to the enhanced accessibility of MoTe2′s most active zones. The physical property of the nanocomposite was established through in-process characterization using different analytical techniques. In a basic environment, the ZnO@MoTe2 combination exhibited a significant value for the generation of hydrogen using electrocatalysts based on ZnO@MoTe2, which was a 34 mV dec-1 Tafel slope. The nanocomposite exhibited a higher turn-over frequency rate (TOF) of 2.4 s−1 than pure materials. The ZnO@MoTe2 nanocomposite displays a higher surface area of 1125 cm2 and a low Rct value of 93 Ω. The electrocatalyst exhibits exceptional stability and durability. During 50 h in an alkaline environment, the application of chronopotentiometry reveals no substantial decrease in potential. The utilization of nanocomposite based electrocatalysts has been shown to provide efficient quick charge kinetics, a noteworthy observation. The results of this study offer a novel, reliable and effective electrocatalyst that has potential applications in the advancement of electrocatalytic devices for hydrogen gas (H2) production. These devices can be developed employing cost-effective technologies and naturally occurring materials widely available worldwide.

Metal-grade laminated nanofiber films with outstanding EMI shielding performances and high-temperature resistance

With the growing demands in electronics, communications, and energy, conductive composites face a daunting challenge as criteria for conductivity and mechanical properties rise. Extensive search on nanocomposites and amorphous metals has been motivated by the quest for a conductive material that can enhance strength and deformability. However, finding conductive materials that can overcome the drawbacks of their conventional counterparts and exhibit great strength, toughness and quick charge transmission while accomplishing large-scale production remains a significant challenge. This paper describes an approach to high-temperature flexible conductive materials by utilizing composites composed of aramid nanofiber (ANF) and silver nanoparticles (Ag NPs). The ANF is derived from macro-aramid fibers and retains its excellent mechanical properties and heat resistance. Within the composite, Ag NPs effectively enter the special nanofiber matrix to build a tightly connected conductive pathway on the ANF, thus facilitating efficient charge transport. The resulting Ag-ANF composite films exhibit an impressive electrical conductivity of 36,989.68 S m−1 and a tensile strength of 30.3 MPa. Additionally, they provide outstanding EMI shielding with a value of 107.9 dB. This significant achievement opens up the possibility of metallizing the surface of insulated polymer fibers, thereby enabling effective EMI shielding applications even in challenging and extreme conditions.

Astonishing performance improvements of dry-film graphite anode for reliable lithium-ion batteries

The electric vehicle (EV) market now requires advanced graphite anodes that can enable both high loading and quick charging. However, meeting these requirements simultaneously is challenging because of uneven electrochemical reactions and Li-plating on the surface of graphite anodes during fast-charging. In this study, high current density graphite anodes (≈6 mA cm−2) were fabricated through a solvent-free dry-electrode process using homogeneously dispersed polytetrafluoroethylene fibrils (2.0 wt% in electrode). This approach significantly improved the mechanical properties and electrochemical performance of graphite anodes during charge/discharge cycles. Dry-processed graphite anodes outperformed conventional wet-processed electrodes in terms of rate performance and capacity retention. Furthermore, LiNi0.6Co0.2Mn0.2O2 (NCM)/graphite coin-type full cells are rapidly charged at a 3C-rate to induce Li-plating on the graphite surface. Thus, dry-processed graphite anodes exhibited less Li-plating than wet-processed anodes, implying that dry-processed electrodes are capable of fast-charging even under high-loading conditions. In addition, dry-processed graphite anodes retain 88.2 % capacity retention after 300 cycles, indicating a stable full-cell operation. Consequently, this research highlights the dry-electrode process as an innovative technique for electrode manufacturing, with the potential to reduce battery production costs while improving electrochemical performance during fast-charging.