Energy Storage Applications Research Articles

High-energy density asymmetric supercapacitors with bimetallic Mo-Ni sulfides anchored on boron carbon nitride matrix

One of the current challenges in energy storage applications is the development of electrode materials that can generate high specific capacitance with considerable energy and power density. Here, our work demonstrates the fabrication of hierarchical MoNiS (Molybdenum Nickel Sulfide) anchored BCN (Boron Carbon Nitride) nanosheets as an anode electrode material for the production of asymmetric supercapacitor (ASSC) device. The facile in-situ hydrothermal reactions are utilized for the synthesis of MoNiS and MoNiS/BCN nanostructures used as electrocatalysts in supercapacitor applications. The morphological and structural analysis confirmed the successful integration of MoNiS flowers anchored on the BCN hybrid matrix. As an electroactive material, MoNiS/BCN nanostructures with the optimized mass have exhibited outstanding electrochemical activity with a specific capacitance of 1157 Fg−1 at 1 A g−1 current density, 96 % of its initial retention after 10,000 consecutive GCD cycles in 1 M of KOH electrolyte. The MoNiS/BCN/AC asymmetric device comprises an anode (MoNiS/BCN) and cathode (AC) with an excellent specific capacitance of 56.2 F g−1 at 1 Ag−1 with a high energy density of 70 Whkg−1 at power density 1200 Wkg−1. The combination of MoNiS and BCN is favoured by the exposure of several electrochemical active sites for rapid transportation of electron and electrolyte diffusion, resulting in better cycling retention. Our research suggests a simple and affordable method for creating transition sulfide materials with BCN nanostructures for application in energy storage systems.

Realizing preparation of zinc anode through regulating electrodeposition current density for aqueous zinc-ion batteries

Aqueous zinc-ion batteries (ZIBs) have shown great potential for large-scale application of energy storage, and the crystal orientation of zinc (Zn) anode is closely related to the battery performance. In order to further clarify the relationship between Zn(002) plane and battery performance, the dense Zn layers was deposited by pulse current on annealed copper foils. The relationship between pulse current density and Zn(002) plane percentage was investigated, and the relationship between Zn(002) plane and battery performance was clarified. The results show that the orientation consistency of deposited Zn layers becomes better with the increasing of current density, and Zn(002) plane percentage gradually increases. The Zn anode was prepared with the current density of 30 mA cm−2, and the assembled full cell exhibits more stable cycling performance, meanwhile, the Coulombic efficiency of nearly 100 % can still be maintained after cycling for 500 cycles. The performance of aqueous ZIBs significantly improves with the increasing of Zn(002) plane percentage.

Effect of temperature and frequency on the dielectric behaviour of cellulose nanocrystals

Nanocellulose is a promising material for advanced applications due to its renewable nature, non-toxicity, eco-friendliness, mechanical strength and other unique properties. This study investigates the dielectric properties of cellulose nanocrystals (CNCs) derived from wastepaper through acid hydrolysis, across a temperature range of 30°C to 100°C and a frequency range of 1 Hz to 10 MHz. Using theoretical models such as the modified Cole-Cole model, Jonscher's universal dielectric response (UDR) model and modified Kohlrausch-Williams-Watts (KWW) model, a detailed analysis is performed. The results indicate that the dielectric properties depend on temperature, with the frequency dispersion of the real (ε′) and imaginary parts (ε″) of the dielectric permittivity fitting the modified Cole-Cole equation. These values show an initial increase up to 70°C (ε′∼ 6000 and dielectric loss <1) followed by a decrease at higher temperatures, which is linked to the hydroxyl groups. A temperature dependence is also observed in space charge conductivity, free charge conductivity and relaxation time. Non-Debye type behaviour is attributed to asymmetrical features in the electric modulus spectra, as explained by the modified KWW model at various temperatures. The frequency variation of AC conductivity adheres to Jonscher’s power law and the temperature variation of the frequency exponent (0≤ s ≤1) indicates a correlated barrier hopping conduction mechanism for charge carriers. Overall, these findings highlight CNCs as excellent candidate for antistatic applications, demonstrating conductivity ranging from 10−5 to10−9 Scm−1. The results also suggest CNCs can be used in energy storage applications due to their outstanding dielectric properties and low dielectric loss (<1).

Flexible and free-standing MXene decorated biomass-derived carbon cloth membrane anodes for superior lithium-ion capacitors

Two-dimensional transition metal materials, MXenes, have attracted tremendous attention in energy storage applications due to their layered structure, good electrical conductivity, and abundant functional groups. In this work, Ti3C2Tx MXene nanosheets and carbon nanotubes (CNTs) were uniformly sprayed and successfully loaded on the cotton nonwoven fabric-derived carbon cloth (CC) substrate by electrostatic self-assembly. The as-prepared flexible MXene-CNTs-CC membrane electrodes with enlarged interlayer spacing and high conductivity fabric support exhibited excellent electrochemical performance. In terms of lithium-ion batteries, the optimized MXene-CNTs-CC anode delivered an ultrahigh initial discharge capacity of 2277.5 mAh g−1 at 0.1 A g−1 along with notable cyclability (1149.8 mAh g−1 after 100 cycles) and rate capability (544.1 mAh g−1 after 200 cycles at 2 A g−1) in half cells. The full cells assembled with LiCoO2 cathode also displayed good cycling stability with a high reversible discharge capacity of 833.5 mAh g−1 after 100 cycles at 0.1 A g−1. Remarkably, the further constructed lithium-ion capacitors with the designed porous carbon nanofiber cathode could maintain energy densities of 121.5 to 20.8 Wh kg−1 with the corresponding power densities of 125 to 12,500 W kg−1, and achieved capacitance retention of 76.3 % after 10,000 cycles at 1 A g−1, demonstrating excellent long-term cycle durability.

Saponification residue–sodium nitrate morphologically stable phase-change materials for medium- and high- temperature thermal energy storage

Saponification residue (SR) is a by-product of the chlor-alkali process used to produce propylene oxide. Owing to its high porosity and large specific area, SR is suitable as a carrier in the preparation of composite phase-change materials (CPCMs). This approach not only addresses the leakage issues associated with phase-change energy storage materials but also utilises solid waste. Herein, a morphologically stable CPCM was prepared using industrial SR solid waste and a phase-change material (sodium nitrate) via a hybrid sintering method. Phase analyses by X-ray diffractometer showed good chemical compatibility between sodium nitrate and SR. Further, scanning electron microscopy showed that SR has a porous structure, and sodium nitrate can be stably adsorbed on the pores and surface of SR. The maximum compressive strength of SR-CPCM was 43.37 MPa. Moreover, the highest loading capacity of SR for sodium nitrate was 50 wt%, resulting in no leakage and remarkable morphological stability. Differential scanning calorimetry indicated that SR-CPCM exhibited adequate thermal stability and that the latent heat increased with rising nitrate content, reaching a maximum value of 99.24 J/(g·°C). Importantly, after 100 thermal cycles, SR-CPCM demonstrated good stability in terms of chemical compatibility and latent heat. These results demonstrate the potential of SR as a carrier material for energy storage applications.

Facile synthesis and characterization of zinc molybdate (ZnMoO4) nanosheets for electrochemical supercapacitor application

Abstract This study explores the synthesis and characterization of zinc molybdate (ZnMoO4) nanosheets with emphasis on their potential application for energy storage devices particularly supercapacitors. The synthesis of ZnMoO4 nanosheets was done through co-precipitation followed by examination of their structure, morphology, optical, thermal behaviour and electrochemical performance by various characterization techniques. X-ray diffraction (XRD) analysis confirmed that the formation of monoclinic ZnMoO4 phase with the average crystallite size 17.93 nm. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) revealed that this material had nanosheets-like structure which helps to increase ion transport and surface area; these two factors are essential for enhancing the material’s supercapacitor efficacy. The semiconductor characteristics were determined using UV–Visible diffuse reflectance spectroscopy (UV-DRS) which indicated a band gap energy of 4.2 eV. Fourier transform infrared (FTIR) analysis confirmed that the presence of Zn–O and Mo–O bonds in their crystal lattice. Thermogravimetric analysis (TGA) showed that the ZnMoO4 nanosheets had thermal stability since they experienced only a slight mass loss of 2.57 % up to 800 °C. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) tests were undertaken to find out the specific capacitance and the value is 618 F g⁻1 at a current density of 1 A g⁻1.

Retraction Note: Titanium carbide nanoparticles filled PVA-PAAm nanocomposites: structural and electrical characteristics for application in energy storage

Retraction Note: Titanium carbide nanoparticles filled PVA-PAAm nanocomposites: structural and electrical characteristics for application in energy storage

Strengthen Water O−H Bond in Electrolytes for Enhanced Reversibility and Safety in Aqueous Aluminum Ion Batteries

AbstractAqueous aluminum‐ion batteries present a promising prospect for large‐scale energy storage applications, owing to the abundance, inherent safety, and the high theoretical capacity of aluminum. However, their voltage output and energy density are significantly hindered by challenges such as complex hydrogen evolution and uncontrollable solvation reactions. In this work, we demonstrate that water decomposition is restrain by increasing the electron density of water protons and increasing the dissociation energy of H2O through robust dipole interactions with highly polar dimethylformamide (DMF) molecules. Moreover, the incorporation of dimethyl methylphosphonate (DMMP) flame retardant effectively addresses the flammability risk arising from a substantial presence of organic additives The in‐depth study with experimental and theoretical simulations reveals that the water‐poor solvation structure with reduced water activity is achieved, which can (i) effectively mitigate undesired solvated H2O‐mediated side reactions on the Al anode; (ii) boost the de‐solvation kinetics of Al3+ while preventing cathode structural distortion; (iii) reduce the flammability of hybrid electrolytes. As a proof of concept, the Al//AlxMnO2 full cell employing a hybrid electrolyte demonstrate enhanced stability (deliver 335 mAh g−1 while retaining 71 % capacity for 400 cycles) compared to those with pure electrolyte.

Modified Si3N4 filler enhancing the energy storage performance and thermal stability of a P(VDF‐HFP) based composite

AbstractTo improve the high‐temperature stability of poly(vinylidene fluoride hexafluoropropylene) P(VDF‐HFP)‐based composite film for its potential application in energy storage, the modified silicon nitride (mSi3N4) nanoparticles are fabricated using silane coupling agent (KH‐570) and introduced into P(VDF‐HFP). When the mass fraction of mSi3N4 is 7.5 wt%, the recoverable energy density (Wrec) of the mSi3N4/ P(VDF‐HFP) composite film reaches to 1.79 J/cm3 under a 125 MV/m electric field, which is 82.7% higher than pure P(VDF‐HFP). Interestingly, the dielectric properties of mSi3N4/P(VDF‐HFP) show a considerable thermal stability at a high‐frequency ranging from −20 to 160°C, providing an effective approach for preparing energy storage composites working for high‐temperature environments.

Long-Range Proton Channels Constructed via Hierarchical Peptide Self-Assembly.

The quest to understand and mimic proton translocation mechanisms in natural channels has driven the development of peptide-based artificial channels facilitating efficient proton transport across nanometric membranes. It is demonstrated here that hierarchical peptide self-assembly can form micrometers-long proton nanochannels. The fourfold symmetrical peptide design leverages intermolecular aromatic interactions to align self-assembled cyclic peptide nanotubes, creating hydrophilic nanochannels between them. Titratable amino acid sidechains are positioned adjacent to each other within the channels, enabling the formation of hydrogen-bonded chains upon hydration, and facilitating efficient proton transport. Moreover, these chains are enriched with protons and water molecules by interacting with immobile counter ions introduced into the channels, increasing proton flow density and rate. This system maintains proton transfer rates closely resembling those in natural protein channels over micrometer distances. The functional behavior of these inherently recyclable and biocompatible systems opens the door for their exploitation in diverse applications in energy storage and conversion, biomedicine, and bioelectronics.

Special Issue: Building Decarbonization

Abstract Emission of carbon dioxide and other greenhouse gases from human activities are considered the main contributors to the global temperature rise over the past several decades. The substantial carbon footprint of buildings stems from emissions due to buildings' energy and water usage (operational carbon) and the emissions from materials and products used for buildings during manufacturing, transportation, installation, and decommissioning (embodied carbon). As countries strive to better understand and mitigate the impacts of climate change, decarbonizing the building sector is considered a critical priority and an opportunity. This special issue brings together a collection of articles that explore innovative approaches and technologies aimed at reducing carbon emissions across various aspects of building design, construction, and operation. The Special Issue covers a wide list of topics related to building decarbonization ranging from innovative heating/cooling technologies, use of renewable energy sources, energy storage applications, novel materials for building envelopes, and review of technologies for building decarbonization in high-density urban areas.

Biomass-derived materials for energy storage and electrocatalysis: recent advances and future perspectives

AbstractOver the last decade, there has been significant effort dedicated to both fundamental research and practical applications of biomass-derived materials, including electrocatalytic energy conversion and various functional energy storage devices. Beyond their sustainability, eco-friendliness, structural diversity, and biodegradability, biomass-derived materials provide additional benefits, including naturally organized hierarchical structures, rich surface properties, and an abundance of heteroatoms. These characteristics make them appealing candidates for effective energy storage and electrocatalytic energy conversion applications. This review explores the recent advancements in biomass-derived materials for energy storage system (ESS), including supercapacitors and electrocatalytic reactions. We also address the scientific and technical hurdles associated with these materials and outline potential avenues for future research on biomass-based energy conversion applications. By emphasizing the significance of controllable structural designs and modifications, we highlight their crucial roles in advancing this field. Graphical Abstract

Advancing Electrical Engineering with Biomass-derived Carbon Materials: Applications, Innovations, and Future Directions.

The ongoing global shift towards sustainability in electrical engineering necessitates novel materials that offer both ecological and technical benefits. Biomass-derived carbon materials (BCMs) are emerging as cornerstones in this transition due to their sustainability, cost-effectiveness, and versatile properties. This review explores the expansive role of BCMs across various electrical engineering applications, emphasizing their transformative impact and potential in fostering a sustainable technological ecosystem. The fundamentals of BCMs are investigated, including their unique structures, diverse synthesis procedures, and significant electrical and electrochemical properties. A detailed examination of recent innovations in BCM applications for energy storage, such as batteries and supercapacitors, and their pivotal role in developing advanced electronic components like sensors, detectors, and electromagnetic interference shielding composites has been covered. BCMs offer superior electrical conductivities, tunable surface chemistries, and mechanical properties compared to traditional carbon sources. These can be further enhanced through innovative doping and functionalization techniques. Moreover, this review identifies challenges related to scalability and uniformity in properties and proposes future research directions to overcome these hurdles. By integrating insights from recent studies with a forward-looking perspective, this paper sets the stage for the next generation of electrical engineering solutions powered by biomass-derived materials, aligning technological advancement with environmental stewardship.

Iodine Boosted Fluoro-Organic Borate Electrolytes Enabling Fluent Ion-conductive Solid Electrolyte Interphase for High-Performance Magnesium Metal Batteries.

Rechargeable magnesium batteries are regarded as a promising multi-valent battery system for low-cost and sustainable energy storage applications. Boron-based magnesium salts with terminal substituent fluorinated anions (Mg[B(ORF)4]2, RF = fluorinated alkyl) have exhibited impressive electrochemical stability. Nevertheless, their deployment is hindered by the complicated synthesis routes and the surface passivation of Mganode. Herein, we report the design of an advanced electrolyte formulation comprised of B(HFIP)3and I2in 1,2-dimethoxyethane (DME), which eventually convert into a Mg[B(HFIP)4]2/DME-MgI2 electrolyte system upon interacting with Mg anode. The Mg anode reacts with I2 and the electron-accepting B(HFIP)3, leading to the in-situ formation of a solid-electrolyte interphase layer composed of MgF2 and MgI2 species that can facilitate fast and stable Mg plating/stripping. Compared with the pristine Mg[B(HFIP)4]2/DME electrolyte, the Mg[B(HFIP)4]2/DME-MgI2 electrolyte exhibited superior electrochemical performance including an ultra-low overpotential (~80 mV), high Coulombic efficiency and a long-cycling period over 1500 h. In result, the rechargeable magnesium batteries with Mg[B(HFIP)4]2/DME-MgI2 electrolyte and Mo6S8 cathode show outstanding compatibility, rapid kinetics, and stable cyclability for over 1200 cycles, surpassing all previously reported boron-based electrolytes. This work introduces a promising halogen-enhancement strategy for boron-based Mg-ion electrolytes and is pivotal for the advancement and optimization of multi-valent secondary batteries.

Iodine Boosted Fluoro‐Organic Borate Electrolytes Enabling Fluent Ion‐conductive Solid Electrolyte Interphase for High‐Performance Magnesium Metal Batteries

Rechargeable magnesium batteries are regarded as a promising multi‐valent battery system for low‐cost and sustainable energy storage applications. Boron‐based magnesium salts with terminal substituent fluorinated anions (Mg[B(ORF)4]2, RF = fluorinated alkyl) have exhibited impressive electrochemical stability. Nevertheless, their deployment is hindered by the complicated synthesis routes and the surface passivation of Mg anode. Herein, we report the design of an advanced electrolyte formulation comprised of B(HFIP)3 and I2 in 1,2‐dimethoxyethane (DME), which eventually convert into a Mg[B(HFIP)4]2/DME‐MgI2 electrolyte system upon interacting with Mg anode. The Mg anode reacts with I2 and the electron‐accepting B(HFIP)3, leading to the in‐situ formation of a solid‐electrolyte interphase layer composed of MgF2 and MgI2 species that can facilitate fast and stable Mg plating/stripping. Compared with the pristine Mg[B(HFIP)4]2/DME electrolyte, the Mg[B(HFIP)4]2/DME‐MgI2 electrolyte exhibited superior electrochemical performance including an ultra‐low overpotential (~80 mV), high Coulombic efficiency and a long‐cycling period over 1500 h. In result, the rechargeable magnesium batteries with Mg[B(HFIP)4]2/DME‐MgI2 electrolyte and Mo6S8 cathode show outstanding compatibility, rapid kinetics, and stable cyclability for over 1200 cycles, surpassing all previously reported boron‐based electrolytes. This work introduces a promising halogen‐enhancement strategy for boron‐based Mg‐ion electrolytes and is pivotal for the advancement and optimization of multi‐valent secondary batteries.

Potential of the Use of Sodium Chloride (NaCl) in Thermal Energy Storage Applications

ABSTRACTEnergy storage is a group of technologies that decrease the gap between energy supply and energy demand. Thermal energy storage (TES) reduces this gap at not only different temperatures but also at different places or power. Design criteria include the integration of the storage system into the whole application system, maximum load, and high‐energy density. Since energy density is given by the material used, the selection of the storage material is key to the success of any energy storage system. In this paper, the potential of sodium chloride (NaCl) to be used in TES, both using sensible TES and latent TES, is evaluated for low‐temperature applications and for high‐temperature ones. This material is found to have high potential for successful applications, both in buildings and in industry.

Tailoring Intrinsic Oxygen Vacancies in P3-Type Na0.66Mn0.66Mg0.33O1.93 to Enhance Oxygen Redox Activity.

Integrating oxygen redox reactions with transition metal redox reactions offers a promising strategy to double or triple the energy density for large-capacity battery cathodes. In this study, we have introduced intrinsic oxygen vacancies (VO) into a P3 layered cathode to modulate the electronic structure of O atoms and enhance oxygen redox activity. Rietveld-refined X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), and X-ray photoelectron spectroscopy confirm the successful creation of VO in Na0.66Mn0.66Mg0.33O1.93 (OV-NMM). Density functional theory (DFT) calculations reveal that VO in OV-NMM positively enhances the antibonding interaction between Mn and O, directing excess electrons from O holes toward adjacent Mn t2g and O 2p orbitals. This modification significantly improves the reversibility and accelerates Na+ transport kinetics for O2-/O- redox reactions. Ex situ synthon-based XRD demonstrates that VO effectively eliminates the O3 phase, reduces Mg2+ migration, and suppresses irreversible structural changes. XAS of Mn K-edge and O K-edge further illustrate the advantageous role of oxygen vacancies in facilitating oxygen redox reactions. These findings highlight the potential of defect engineering, particularly VO, to boost anionic redox activity for high-capacity energy storage applications.

Development and Characterization of 3D-Printed PLA/Exfoliated Graphite Composites for Enhanced Electrochemical Performance in Energy Storage Applications

This research introduces a new way to create a composite material (PLA/EG) for 3D printing. It combines polylactic acid (PLA) with exfoliated graphite (EG) using a physical mixing method, followed by direct mixing in a single-screw extruder. Structural and vibrational analyses using X-ray diffraction and Fourier transform infrared spectroscopy confirmed the PLA/EG’s formation (composite). The analysis also suggests physical adsorption as the primary interaction between the two materials. The exfoliated graphite acts as a barrier (thermal behavior), reducing heat transfer via TG. Electrochemical measurements reveal redox activity (cyclic voltammetry) with a specific capacitance of ~ 6 F g−1, low solution resistance, and negligible charge transfer resistance, indicating ion movement through a Warburg diffusion process. Additionally, in terms of complex behavior (electrochemical impedance spectroscopy), the PLA/EG’s actual capacitance C’(ω) displayed a value greater than 1000 μF cm−2, highlighting the composite’s effectiveness in storing charge. These results demonstrate that PLA/EG composites hold significant promise as electrodes in electronic devices. The methodology used in this study not only provides a practical way to create functional composites but also opens doors for new applications in electronics and energy storage.

Graphene‐based Supercapacitor Using Microemulsion Electrolyte

AbstractGraphene‐like material prepared by a facile combustion synthesis was investigated as an electrode material in a microemulsion electrolyte. Notably, a stable voltage window of 2.2–2.4 V was achieved, surpassing previous reports for aqueous‐based electrolytes on similar materials. The fabricated supercapacitor device exhibited a commendable specific capacitance values of 59 F g−1 at 0.1 A g−1 and 32 F g−1 at 5 A g−1, indicating its potential for high‐current applications. Mechanistic examination revealed that the charge storage primarily relies on electric double‐layer formation, with minor non‐capacitive contribution from electrode surface functionalities and the supporting electrolyte. Further analysis showed significant capacitive contributions of 85 % at 2.2 V and 67 % at 2.4 V, underscoring the dominance of the capacitive process. The fabricated supercapacitor's stability indicated a decrease as the non‐capacitive process intensified, suggesting that electrode surface functionalities predominantly contribute to cell deterioration at elevated potentials. These results highlight the potential efficacy of microemulsion electrolytes in energy storage applications.

Investigation of Bi2MoO6/MXene nanostructured composites for photodegradation and advanced energy storage applications

This study presents nanostructured composite Bi2MoO6/MXene heterostructure by using hydrothermal method for photodegradation of the congo-red dye and also for energy storage devices. X-ray diffractometer (XRD), High Resolution Transmission Electron Microscopy (HRTEM), Field emission scanning electron microscope (FESEM) and X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) were performed to examine the structural properties along with surface area and porosity of the material. Due to addition of MXene the larger surface area and improved pore size help to quickly break down additional organic pollutants by adsorbing them. The band gap of Bi2MoO6/MXene nanostructured composite reduced to 2.4 eV suggesting transfer of electrons from VB to CB. Bi2MoO6/MXene exhibits a high (92.3%) photocatalytic degradation rate for a duration of 16 min which was verified using UV-visible spectroscopy, also scavenger test was conducted to ascertain the reactive agent along with the degradation pathway was confirmed by LCMS. Elemental content was also established by using inductively coupled plasma mass spectrometry (ICP-MS). For estimating energy storage capacity cyclic voltammetry (CV) was performed. It was observed Bi2MoO6/MXene nanostructured composite electrodes had specific capacitance of 642.91Fg− 1, power density of 1.24 kWkg− 1, and energy density of 22.32 Whkg− 1 at a current density of 5Ag− 1 also it exhibited 64.42% capacity retention having current density 20 Ag− 1 throughout 10,000 Galvanostatic charge discharge (GCD) cycles. High electrical conductivity of Bi2MoO6/MXene electrode was again examined by Electrochemical impedance spectroscopy (EIS). These findings demonstrate the potential of Bi2MoO6/MXene nanostructured composites in both photodegradation and energy storage applications.