Electrochemical Storage Applications Research Articles

Catalytic and Electrochemical Study of Cu-ZSM-5/MCM-41.

Hierarchically structured micro-mesoporous ZSM-5/MCM-41 composite materials incorporating copper ions were synthesized using pre-synthesized ZSM-5 and cetyltrimethylammonium bromide (CTAB) as a template for forming the MCM-41 structure. The composites were characterized through powder X-ray diffraction, N2 adsorption-desorption, diffuse reflectance spectroscopy (UV-vis DRS), Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy dispersive X-ray spectroscopy. X-ray diffraction confirmed well-ordered ZSM-5 and MCM-41 structures, and UV-vis DRS showed successful copper ion incorporation. N2 adsorption-desorption revealed the presence of both microporous and mesoporous structures. To evaluate their catalytic performance, Cu-incorporated ZSM-5/MCM-41 composite catalysts were assessed through the oxidation reaction of ethylbenzene using tert-butyl hydroperoxide (TBHP) as the oxidizing agent. With a 9% (w/w) Cu-ZM-5 (5 wt % copper-incorporated ZSM-5/MCM-41) catalyst and an oxidant to ethylbenzene molar ratio of 2:1 at 40 °C in the absence of a solvent for 4 h, the process yielded acetophenone (93.2%) as the major product. Additionally, these Cu-incorporated composites were examined as electrode materials for electrochemical storage. Cyclic voltammetry and galvanostatic charge-discharge studies showed that Cu-ZM-5 exhibited pseudocapacitive behavior, with a capacitance of up to 366 F g-1 at a current density of 1 A g-1, surpassing ZSM-5 and ZSM-5/MCM-41. These results highlight Cu-ZM-5's potential as an effective electrode material for electrochemical storage applications like supercapacitors.

Enhancing the supercapacitive performance of soot material induced with manganese cobaltite (MnCo2O4) for supercapacitor application

Processing waste carbonaceous materials into useful products presents a sustainable alternative to its recovery. An effective and environmentally benign way of reusing such waste is to convert them into electrodes capable of supporting energy conversion reactions. This study introduces a cost-effective synthesis of a composite electrode for supercapacitor application using a waste carbonaceous soot obtained from Tema Steels Limited, a local steel manufacturing company in Ghana, having it subjected through thermal treatment at 500 °C and synergizing with annealed MnCo2O4 to augment the soot’s supercapacitive capabilities. The fabricated composite electrode comprises treated (thermally activated) soot combined with annealed MnCo2O4 material in 1:1 mass ratio, using a facile hydrothermal synthesis technique. Halogen like chlorine negatively affect the supercapacitive performance of soot, the as-received soot was subjected to a 500°C, 2-hour thermal treatment to optimize its performance, effectively reducing chlorine content from 4.1 to 2.1 at. weight percent and notably augmenting its specific surface area (SSA). SSA increased from 183.3 m2g−1 to 253.3 m2g−1, a 27.6 % increment after thermal treatment. The electrode’s supercapacitive performance was utilized using a 3 M KOH electrolyte solution employed in a three-electrode system. Attaining a current density of 3Ag−1, the composite electrode achieved a specific capacitance of 2818 Fg−1. The fabricated composite electrode demonstrated a stable charge/discharge capability by retaining around 87 % of its capacity after 10,000 cycles, establishing its practicality for applications in electrochemical storage.

Green synthesis of g-C3N4 decorated with SnO2 nanocomposites using a novel Ananas comosus crown extract for boosted performance of asymmetric supercapacitors

The recent development of green chemistry, when preparing nanoparticles using plants and their various parts has received a lot of attention in today's world. Metal and metal oxide nanoparticles have gained recognition for their recent advances in green synthesis. In this work, the green synthesis of a 2D g-C3N4 nanosheet decorated with SnO2 nanocomposite was prepared by Ananas comosus crown extract for electrochemical storage applications. The novel Ananas comosus crown extract acts as a reducing or capping agent for a green approach. The prepared g-C3N4/SnO2 nanocomposites were studied with structural, functional group, morphological, elemental composition, chemical state, and surface area analysis of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET). SnO2 and various concentrations of g-C3N4 (25, 50, 75 & 100 mg) nanocomposite were investigated for electrochemical performance. At a current density of 1 Ag−1, the green synthesized (SnO2/g-C3N4 (50 mg)) SCN-50 nanocomposite displays a high specific capacitance of 302.7 Fg−1, as well as the composite demonstrates excellent capacitance retention of 94 % after 10,000 loops. Moreover, the asymmetric supercapacitor device of SnO2/g-C3N4//Activated carbon performed good reversible and cyclic stability with high energy and power density. The green synthesis of SnO2/g-C3N4 nanocomposite has promising electrode materials for future energy storage devices.

Synthesis and characterization of ZnO-NiO nanocomposites for photocatalytic and electrochemical storage applications

Synthesis and characterization of ZnO-NiO nanocomposites for photocatalytic and electrochemical storage applications

Investigation of cathode properties of two-dimensional NbS2Cl2 for Li and Na-ion batteries using density functional theory

Exploring novel two-dimensional materials (2D) for electrode and electrochemical storage applications stands as a pivotal pursuit in advancing renewable energy technologies. While recent research has predominantly focused on anode materials, cathode materials have received comparatively lesser attention. This study delves into the potential cathode applications of the novel two-dimensional material NbS2Cl2 using density functional theory. Fundamental properties, encompassing electronic and thermodynamic attributes, were scrutinized to comprehend the material’s characteristics. Our investigation extended to examining the adsorption and diffusion properties of these electrode materials. Comprehensive calculations of mechanical and thermodynamic properties reaffirmed the stability of this system. Upon adsorption of Li/Na atoms, the conducting nature emerged, evident through charge density difference and projected density of states. Our findings notably reveal minimal diffusion barriers of 1.5 eV and 0.35 eV for Li and Na atoms. Moreover, the observed open circuit voltages for adsorbed Li and Na ions were 4.69 V and 2.62 V, respectively. The calculated theoretical capacity for adsorbed Li-ion on 2D-NbS2Cl2 is 400 mAh g−1, while for Na-ion adsorption, it is 353 mAh g−1, awaiting validation through future experimental verifications.

Development of zinc nitrate hexahydrate salt (ZNH)/ethylene glycol (EG) binary composite deep eutectic electrolytes

In this study, zinc nitrate hexahydrated (ZNH)/ethylene glycol (EG) binary composite deep eutectic solvent (DES) were developed by a combination of hydrogen bond acceptor (HBA) (i.e.ZNH) and hydrogen bond donor (HBD) (i.e. EG) at various molar ratios (1:3, 1:4, 1:5 and 1:6) using heating method. The electrochemical and physicochemical properties DES were analyzed using Ionic conductivity (σ), refractive index, density, viscosity, thermogravimetric (TGA), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), and electrochemical impedance (EIS). The results revealed that DES 1:6 exhibited the lowest viscosity values of 579, 381, 119, 110, and 58 mPa s at shear rate values of 20, 30, 60, 100, and 200 (s−1) respectively. Similarly, the lowest values of density (1.392 g/cm3) and lowest values refractive index (1.441) and highest value of σ (7.51 mS/cm) were obtained. The cyclic voltammetry (CV) result also presented a wider range value of electrochemical potential window (EPW) (i.e. 1.06 V) showing the reversibility of electrochemical electrolytes due to the delocalization of charged ions that creates a bigger void volume inside the solution. Hence, these findings show that DES with the molar ratio of 1:6 can be a potential solvent for different electrochemical storage applications.

Binary glycerol-based deep eutectic solvents containing zinc nitrate hexahydrate salt for rechargeable zinc air batteries applications with enhanced properties

Deep eutectic solvents (DESs) have attracted interest due to their unique and favorable electrochemical characteristics. This study reported a novel binary glycerol-zinc salt deep eutectic solvents were prepared with a combination of hydrogen bond donor (glycerol (Gly)) and hydrogen bond acceptor (Zinc nitrate hexahydrate (ZNH)) at different molar ratios of 1:2, 1:3, 1:4, 1:5, and 1:6. The various physicochemical properties including viscosity, refractivity index, conductivity, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance (EIS) were measured. The results showed that among the various combinations tested, DES 1:2 resulted in a low viscosity value of 690, 500, 310, 220, and 160 mPa (mPa s) at shear rate (S−1) values of 20, 30, 60, 100, and 200 respectively. Moreover, DES 1:2 resulted in more electrochemically stable solvents with a lower refractive index value of 1.446, and a higher conductivity (σ) of 4.41 mS/cm. The findings found disclose the features, nature and of properties of prepared DESs as a potential solvents for different electrochemical storage applications.

Biocarbon Derived from Seeds of Palmyra Palm Tree for a Supercapacitor Application

Carbon-based materials are among the most promising materials for future electrochemical energy storage and conversion. Eco-friendly Palmyra palm seed derived microporous biocarbon was fabricated on the graphitic sheet. Palm seed derived carbon was carbonized by using 0.5 M H2S04 without any activating agent. Morphological characterization of PSDC investigated through SEM (Scanning Electron Microscopy). It shows PSDC is microporous with carbon network like structure. Physiochemical characterization performed through XRD, FT-IR and Raman studies. Raman studies confirm the PSDC having carbon based material. Electrochemical performance by using Cyclic voltammetry (CV), Galvanostatic charge discharge (GCD) and Electrochemical Impedance spectroscopy (EIS). PSDC exhibits the specific capacitance of 220 F/g at 5 A and 276.5 F/g at 1 A current as well as remarkable capacitance retention after 500 cycles is 63.1%. It shows PSDC having remarkable electrochemical storage application.

Ag nanoparticles synthesized by Datura metel L. Leaf extract and their charge density distribution, electrochemical and biological performance

The present study investigates the electrochemical performance; charge density distribution, antimicrobial and antifungal activities of green synthesized silver nanoparticles (Ag NPs) using the leaf extract of Datura metel L. UV–vis absorption spectrum shows that highly stable, monodispersed Ag NPs formed at 418 nm. Particle size analysis with zeta potential values 117 nm, − 27.3 mV are implied that hydrodynamic size with negative surface charges. Fourier transforms infrared (FTIR) analysis identified amide functional groups in Datura metel L. responsible for the reduction and stabilization of nanoparticles. Scanning electron microscopy (SEM) analysis showed about the spherical morphology and Energy Dispersive Absorption X-ray (EDAX) spectrum displays the Ag peak at 3.1 KeV with encapsulation of organic trace elements. X-ray Photoelectron Spectroscopy (XPS) analysis exhibit’s Ag 3d, Ag 3p, and Ag 3s chemical state of Ag NPs and the X-ray Diffraction (XRD) pattern confirmed the crystalline nature at 38.1˚ with organometallic phases. The structure factors in the single unit cells are studied in about three, two, and one-dimensional profiles using the Rietveld refinement technique. The complex of atropine with the nanoparticle was modeled using the MOPS method. The formation of the complex is carried out due to the transfer of the electron density of Ag NPs to the atropine molecule, which consists of more electronegative atoms. A charge transfer complex in which the nanoparticle acquires a charge of +0.354 and the atropine – 0.354 is formed. The synthesized Ag NPs exhibited noticeable antimicrobial, antifungal activity with large–diameter inhibition zones against S. pyogenes (12.1 ± 0.66 mm), E. faecalis (11.8 ± 0.33 mm), K. pneumoniae (10.2 ± 0.44 mm), S. flexneri (10.3 ± 0.21 mm), C. albicans (11.3 ± 0.66 mm), and A. fumigatus (10.5 ± 0.33 mm). The green synthesized Ag NPs as prepared electrode exhibits specific capacitance of 825 F/g at the current density of 3 mA/g in 1 M KOH electrolyte solution and cyclic stability retained at about 88.35% even after 5000 cycles with the current density of 5 mA/g. The results showed their effective utilization of green synthesized Ag NPs in biological and electrochemical storage applications.

Pseudocapacitive Features of Freestanding Nickel-Zinc Organometallic Nanostructure for High-energy Density Coin-cell Asymmetric Supercapacitors.

Binder-free two-dimensional mesh-like structure of nickel-zinc metal-organic framework on in-situ-coated carbon cloth (Ni-Zn MOF/CC) and Ni-Zn MOF powder were developed via a solvo-hydrothermal reaction for electrochemical storage application. The electrochemical properties of these electrodes show that the electrodes self-assembled on carbon cloth substrates exhibit remarkably excellent performance. The Ni-Zn MOF/CC electrode exhibited a capacitance of 653.54 F/g at 1 A/g through a capacity retaining of 87.65% after 10000 cycles. Furthermore, the Ni-Zn MOF//AC coin-cell asymmetric supercapacitor device (CASD) exhibited remarkable energy and power densities of 54.31 Wh/kg and 825 W/kg, respectively, with adequate capacitance retention up to 94.63% over 5000 cycles at 1.5 V. The CASD also exhibited a significant power density of 4950 W/kg at 19.67 W h/kg, which suggests that these in-situ developed MOF-based electrodes may discover application in energy storage devices.

Nano-sized neem plant particles as an electrode for electrochemical storage applications

Nano-sized neem plant particles as an electrode for electrochemical storage applications

In-situ transformation constructs CoTe/Co/CoO nanosheet arrays with rich grain boundaries to enhance electrochemical performance

Development of high conductivity and amorphous structure is at great significance in electrochemical storage applications. Two-dimensional nanosheet array has a large surface area and abundant active sites, showing great potential in the field of energy storage. Among many materials, Co-based oxides or hydroxides have high theoretical specific capacity and are widely used as electrode materials for hybrid supercapacitors, but low electrical conductivity inhibits their development. Here, Co(OH)2 nanosheet arrays are randomly transformed into CoTe, metallic Co, and CoO composite (CoTe/Co/CoO) during the hydrothermal process. The CoTe/Co/CoO nanosheets have abundant grain boundaries due to the multi-component effect. Thanks to the high elasticity of amorphous CoO, and the high conductivity of CoTe and Co, CoTe/Co/CoO composite nanosheet arrays exhibit excellent electrochemical performance, such as high capacity (501 C g−1 at 5 mA cm−2) and excellent cycle stability (95.2% capacity retention after 4000 cycles). Moreover, asymmetric supercapacitors are assembled with CoTe/Co/CoO as positive electrode and activated carbon as negative electrode, the developed device delivers a maximum energy density of 35.29 Wh Kg−1 with superb cycling stability.

Nanoscale Mapping of Cu‐Ion Transport in van der Waals Layered CuCrP2S6

AbstractIonic conduction of metal thiophosphates (MTPs) is attracting growing attention for promising applications in electrochemical storage and tunable physical properties. Especially, metal‐ion migration in copper thiophosphate has been identified as a key factor for the control of their microstructure and phase transition. However, direct evidence for the coupling between Cu‐ion motions and the crystal lattice has been elusive at the nanometer scale. Here, the room temperature diffusion kinetics of Cu ions in layered CuCrP2S6 (CCPS) is demonstrated. A tip‐enhanced electric field based on scanning probe microscopy (SPM) has been used as the driving force for Cu‐ion motions through van der Waals gaps. The strong coupling between Cu‐ion concentration and crystal lattice and the resulting serial structural transitions have been probed directly by the comprehensive utilization of spatially resolved Raman spectra, cross‐section energy dispersion spectrum (EDS), and high‐resolution transmission electron microscopy (HR‐TEM). This knowledge improves the understanding of the effect of intrinsic Cu‐ion migration on the structure transformation in layered van der Waals materials and provides feedback to the nanoscale mechanisms of nanometer devices based on iontronics.

Studies on 2D-molybdenum diselenide (MoSe2) based electrode materials for supercapacitor and batteries: A critical analysis

Two-dimensional (2D) nanomaterials are getting significant attention in the area of energy storage and conversion due to their unique physical, chemical, and electrical properties. Molybdenum dichalcogenides, particularly molybdenum diselenide (MoSe2) have emerged as one of the most promising candidates for energy storage devices. Many MoSe2-based compounds have been synthesized and studied for electrochemical energy storage devices such as supercapacitors, lithium-ion, and sodium-ion batteries. In this review, we summarize the advances made in recent years on the MoSe2-based anode materials and highlight their outcomes in electrochemical storage applications. The electrochemical performance of different composites of MoSe2 is briefly reviewed. The relationship between different morphologies of MoSe2 and their electrochemical performance is also discussed. Also, the role of different supporting species in the MoSe2-based composites has been discussed in detail. Additionally, the positive and negative aspects of the different morphologies of MoSe2 and its composites are also summarized. Finally, the challenges and outlooks on the development of MoSe2 based anode material are proposed.

Electrochemical evidence of the modification of carbon materials with anthraquinone moiety by a Diels Alder process

Interfaces play a key role in electrochemical energy storage. They are directly responsible for performances (and thus indirectly costs), safety and lifetime of the batteries and electrochemical capacitors. A way to improve devices is to control these interfaces and one attractive approach to achieve this goal is to modify electrodes by grafting molecules bearing desired moieties (hydrophilic/hydrophobic, redox…). Diazonium (electro)chemistry is the most popular modification technique in the field of energy storage but it has some limitations. Two major drawbacks are the lack of control on the grafted layer (structure and morphology) and the chemical nature of the diazonium itlself that could, in some cases, makes it difficult to manipulate. Thus, our objective is to propose an alternative option to modify electrodes and, particularly this work aims to validate the use of the Diels Alder reaction to modify carbon materials with redox molecules for electrochemical storage purposes. A new molecule (propargyl anthraquinone) was synthesized to make this Diels Alder reaction possible. The modification was evidenced by electrochemical characterizations, comparing carbon electrodes modified with the synthesized propargyl anthraquinone and other commercial anthraquinone derivatives. The modified carbons were stable in both acidic and buffered neutral conditions and rate capability similar to unmodified carbon. Very interestingly, the electrochemical behavior of our electrodes is comparable to those fabricated by the state-of-the-art diazonium chemistry. In this study, we investigated and validated the possibility to use the Diels Alder reaction to modify carbon for electrochemical storage application. This is a critical input because it allows to expand modification methods suitable to tune interfaces for electrochemical storage applications.

Hierarchical porous oviform carbon capsules with double-layer shells derived from mushroom spores for efficient sodium ion storage

Developing carbon materials with well-defined morphologies using renewable feedstocks is highly desirable for electrochemical energy storage application. Herein, we report a new class of hierarchical porous oviform carbon capsules with double-layer shells, which were synthesized via pyrolysis using the mushroom spores of ganoderma lucidum (mainly comprise chitin) and sodium phytate as precursors and activator, respectively. The resultant one-of-a-kind spores derived carbon capsules as anode for sodium ion battery exhibits a high reversible capacity of 311.5 mA h g−1 at a current density of 0.1 A g−1 and outstanding cyclic stability at current density of 5 A g−1, in which the reversible capacity is 125.0 mA h g−1 and after 5000 charge/discharge cycles, the capacity is 111.1 mA h g−1 with the retention rate of approximately 88.8%. Furthermore, a full cell constructed using the carbon capsules and Na3V2(PO4)3 as anode and cathode respectively shows 158.2 mA h g−1 at 1 A g−1 and maintains high capacity after 500 cycles, further indicating their excellent performance for sodium storage. This outstanding performance for electrochemical Na+ storage is critically ascribed to the specific morphology with double-layered hierarchical porous hollow structure derive from spores. Meanwhile, this work provides a new designing platform for synthesizing advanced carbon materials for electrochemical storage application using the diversity of mushroom spores in nature.

Hierarchal growth of MoS2@CNT heterostructure for all solid state symmetric supercapacitor: Insights into the surface science and storage mechanism

Direct growth of atomically thin hierarchal MoS2 nanoflakes on CVD grown carbon nanotubes has been achieved using magnetron sputtering for electrochemical storage application. This novel technique of preparing MoS2@CNT 1D heterostructure using a combination of CVD and PVD proved to be very efficient in structurally engineering the microstructure of electrode material. The super capacitive measurements of the MoS2@CNT electrode revealed capacity of 337 mF/cm2 at the sweep rate of 5 mV/s. The storage mechanism involves both electrostatic ionic adsorption as well as Na+ intercalation into the MoS2@CNT matrix. Further, using Trassati and Dunn's methods, we found that ionic diffusion and the inner electrode material contributes majorly to the total stored charge. In order to study the phase evolution of electrode material upon several charge-discharge cycles, we employed XPS technique which indicated lower shift in the binding energies of Mo as well as S. This shift indicates partial transition of 2H→1T phase due to the transverse gliding of S plane upon the intercalation of electrolytic ions. The state supercapacitor built using symmetric MoS2@CNT electrodes was found to have high areal and volumetric capacitance of 131 mF/cm2 and 2.9 F/cm3 respectively, with high cyclic stability of 97.6% after 2500 cycles.

Boron acid catalyzed synthesis porous graphene sponge for high-performance electrochemical capacitive storage

Carbon materials possessing porous structure as well as high heteroatom doping content gradually become critical components in various electrochemical storage applications. Here, a facile route based on boric acid catalysis synthesis process was proposed to prepare hierarchical boron-doped graphene sponge. The hydrolyzed intermediate B(OH)+4 from boric acid acts as porous forming agent precisely making contribution to the macro-porous structure of graphene. Benefiting from unique structure and boron doping (2.4%), the obtained graphene sponge exhibits a significant improvement in capacitance (369.2 F g−1 at 2 A g−1) and maintains an outstanding rate capability (174.9 F g−1 at 30 A g−1). After 1500 cycles at 5 A g−1, the sponge electrode still possesses 91.7% of capacitance retention, revealing the promising future as a high-performance electrode material for supercapacitors.

Cellulose nanofibrils-reduced graphene oxide xerogels and cryogels for dielectric and electrochemical storage applications

The effect of structure (density and porosity) and composition (ratio) of composites prepared from cellulose nanofibrils (CNF) and reduced graphene oxide (RGO) as film-like xerogels and porous cryogels, respectively, were investigated related to their dielectric performance and electrochemical storage abilities. A very small content (5 wt%) of RGO incorporated xerogelic film of a denser and layered structure shows relatively high dielectric constant of ∼85 and ∼164 and an ac electrical conductivity of 0.0028 S/m2 and 0.0072 S/m2 at 270 K and 370 K, respectively, at a high frequency of 1 MHz showing their suitability for high temperature dielectric storage applications. On the other hand, a high specific capacitance of ∼460 F/g and electrochemical resistance of 12–15 Ω cm2 was observed for well-aligned and longitudinal-oriented micro-porous cryogel, indicate on its suitability as electrodes for electrochemical storage devices.

Density Functional Theory Modeling of Boron-Doped Graphene Flakes for Electrochemical Storage Applications

In recent years, electrochemical energy storage devices such as lithium ion batteries and lithium sulfur batteries have been intensively developed to meet the increasing demand for portable electronic devices and electric vehicles. Despite such considerable efforts, the performance of the batteries is still limited by the cell voltage drop which is observed during the charging/discharging cycles. Therefore, a suitable methodology need to be systematically developed to design promising cathode material candidates with high redox potentials and thereby inherently maximize the cell voltage. Well-designed materials should be able to not only have the high onset redox potentials but also sustain the high redox potentials without significant voltage drops during the discharging process. In this work, a series of boron-doped graphene materials with various boron concentrations and distributions are designed and investigated using density functional theory modeling. It is stressed in this work that the redox and electronic properties can be tailored by the boron atoms doped on the graphene flakes. This provides better understanding of the redox property of the boron-doped graphene flakes and offers valuable information for the high-performance material design in electrochemical energy storage devices.