Field Of Storage Research Articles

In-Situ Grafting Strategy Enables Functional Separator for Advanced Lithium-Sulfur Batteries.

A functional separator is developed by in-situ grafting nickel tetraaminophthalocyanine (NiTAPc) onto the surface of polypropylene (PP). It is applied to inhibit the shuttle effect of polysulfides (PSs) in lithium-sulfur(Li-S) batteries. The characterization results showed that NiTAPc is highly dispersed and uniformly grafted onto PP separator. In-situ grafting strategy effectively mitigates the self-agglomeration issue associated with NiTAPc and enhances the exposure of catalytically active Ni-N4 sites. These sites exhibit excellent adsorption and conversion capabilities for PSs. This is consistent with the results of theory calculations, which indicate that the presence of NiTAPc can reduce the delithiation energy barrier associated with Li2S conversion. Owingto the excellent inhibition ability of NiTAPc on the shuttle effect of PSs, the Li-S battery employing a PP-NiTAPc separator demonstrates excellent cycle stability. It showsan initial specific capacity of 1256.5mAhg-1 at 0.1 C, and a capacity retention of 582.4mAhg-1 after 500 cycles at 1 C, showcasing a minimal decay rate of 0.0547% per cycle. The strategy adopted in this study offers valuable insights for the development of modified separators for rechargeable batteries and other energy storage fields.

Empowering DNA-Based Information Processing: Computation and Data Storage.

Information processing is a critical topic in the digital age, as silicon-based circuits face unprecedented challenges such as data explosion, immense energy consumption, and approaching physical limits. Deoxyribonucleic acid (DNA), naturally selected as a carrier for storing and using genetic information, possesses unique advantages for information processing, which has given rise to the emerging fields of DNA computing and DNA data storage. To meet the growing practical demands, a wide variety of materials and interfaces have been introduced into DNA information processing technologies, leading to significant advancements. This review summarizes the advances in materials and interfaces that facilitate DNA computation and DNA data storage. We begin with a brief overview of the fundamental functions and principles of DNA computation and DNA data storage. Subsequently, we delve into DNA computing systems based on various materials and interfaces, including microbeads, nanomaterials, DNA nanostructures, hydrophilic-hydrophobic compartmentalization, hydrogels, metal-organic frameworks, and microfluidics. We also explore DNA data storage systems, encompassing encapsulation materials, microfluidics techniques, DNA nanostructures, and living cells. Finally, we discuss the current bottlenecks and obstacles in the fields and provide insights into potential future developments.

A Comparison of the Electrical Properties of Gel Polymer Electrolyte-Based Supercapacitors: A Review of Advances in Electrolyte Materials

Flexible solid-state-based supercapacitors are in demand for the soft components used in electronics. The increased attention paid toward solid-state electrolytes could be due to their advantages, including no leakage, special separators, and improved safety. Gel polymer electrolytes (GPEs) are preferred in the energy storage field, likely owing to their safety, lack of leakage, and compatibility with various separators as well as their higher ionic conductivity (IC) than traditional solid electrolytes. This review covers the classification, properties, and configurations of different GPE-based supercapacitors and recent advancements that have occurred in this area of energy storage. Ionic liquid (IL)-based materials are popular GPEs for electrochemical energy storage and can be used to prepare unprecedented flexible supercapacitors due to their great IC and wide potential range. A comparative assessment of the GPEs-based supercapacitors reveals that in a majority of them, the value of specific capacitance is generally under 1000 F g−1, energy density reaches around 125 Wh kg−1, and the power density is seen to be less than 1500 W kg−1. The results of this research serve as an essential reference for upcoming scholars, and could significantly improve our comprehension of the efficacy of GPE-containing supercapacitors.

Enhancing the Pseudocapacitive Energy Storage of Coordination Polymers by Artificially Constructed Defective Sites Anchoring Redox-Active Species.

Coordination polymers (CPs) have emerged as potential energy storage materials for supercapacitors due to their tunable chemical composition, structural diversity, and multielectron redox-active sites. However, besides poor cycling stability, the practical application of dense CPs in supercapacitors is generally limited by low specific capacitance and high resistance, which are caused by their low specific surface area and dense frameworks, resulting in insufficient redox reactions of metal sites and poor ion diffusion, respectively. Here, we synthesize a new dense CP {CP-1: [Ce(obb)(HCOO)]∞} via self-assembly of the Ce cation and 4,4'-oxidibenzoate (obb2-). The specific capacitance of CP-1 increases by 156.7 times, and its lifetime after charge-discharge for 5000 cycles is elevated from 62 to 86.7%; meanwhile, the resistance of the positive electrode is reduced from 1.05 to 0.73 Ω through this defect engineering strategy (DES), i.e., cyclic voltammetry sweep in a sulfuric acid electrolyte to artificially construct defects for anchoring the redox-active species (ferricyanide anions). To investigate the universality of this strategy, we have applied it to the other two previously reported CPs {CP-2: [Ce4(obb)6(H2O)9·(H2O)]∞ and CP-3: [Ce2(obb)3(OH)(H2O)(DMF)]∞}, which are also obtained by self-assembly of the Ce cation and obb2- ligand. By comparing the electrochemical performances of the three pristine CPs and their corresponding defect-engineered CPs obtained through the DES, we have found that (i) this strategy is effective in enhancing the electrochemical performances for all three CP materials and (ii) the effect of this strategy on improving the electrochemical performance of CP-1 with a three-dimensional dense network is better than that of CP-3 with a layered structure, and both are better than that of CP-2 with small pores. This work demonstrates a new effective universal strategy for boosting the electrochemical performances of CPs, thus advancing their application in the energy storage field.

Image retrievable encryption based on linear fitting and orthogonal transformation

Abstract With the development of cloud computing, an increasing number of resource-constrained image owners tend to store their images in the cloud and rely on image retrieval services to obtain the images they desire. However, the security of the cloud cannot be fully guaranteed. To ensure image security while achieving good retrieval performance, we have designed a retrievable image encryption algorithm based on linear fitting and orthogonal transformation. This algorithm first generates encryption and feature extraction domains through orthogonal decomposition, and then applies a modified ResNet50 network for feature extraction in the feature extraction domain. The encryption process employs an improved affine transformation based on linear fitting, where part of the fitting values comes from the original image data and the other part comes from data generated by a chaotic system. Additionally, to simplify the measurement of feature similarity in the cloud, we have designed a hierarchical feature index tree to narrow the retrieval scope, thereby reducing retrieval complexity. Experimental results show that the proposed algorithm effectively protects image privacy and achieves high retrieval accuracy. The F-score reached 6.7634% on the Ghim10k dataset and 25.514% on the Corel 1K dataset, significantly improving upon traditional methods. This algorithm has potential application value in the fields of secure image storage and efficient retrieval in the cloud.

Ni-In-oxalate nanostructure as electrode materials for high-performance supercapacitors

Energy storage technologies play a crucial role in addressing the intermittent characteristics of renewable energy sources, improving the stability of electrical grids, and decreasing the release of greenhouse gas emissions. In this study, we presented nickel indium oxalate (Ni1-xInxC2O4) as a promising material with potential applications in the field of electrochemical energy storage. The as-prepared Ni-In- oxalate sample was subjected to different physical characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Regarding the electrochemical energy storage capability, the Ni1-xInxC2O4 electrode material exhibited a specific capacitance of 835 F g-1 (417.5 C g-1) at 1 A g-1. The incorporation of nickel into the indium oxalate nanoplates enhances their electrochemical performance. The presence of nickel in the nanoplates generated from substrate, improving the overall conductivity of the material and enhances its electrochemical reactions, thus leading to improved energy storage capabilities.

Improved synthetic method for the color-tunable LiYGeO4:Tb3+ persistent phosphor toward information storage

Efficient and stable persistent phosphors play a crucial role in the fields of energy storage, anti-counterfeiting, and biomedical fields. Here, we present an improved synthetic method for preparing a series of color-tunable LiYGeO4:Tb3+ persistent phosphor. The increased Tb3+ concentration in the improved method enhances the persistent luminescent intensity at 20 s by ∼ 2.96 times. This enhancement is due to the dual roles of Tb3+ as both emitters and trap centers within LiYGeO4. By simply increasing the doping concentrations, the persistent color can be adjusted from blue to green. LiYGeO4:Tb3+ exhibits no loss of persistent luminescent intensity even after exposure to water at 80 °C for 72 hours, surpassing the commercial green persistent phosphor. Furthermore, information storage was successful demonstrated by using LiYGeO4:Tb3+ with various doping concentrations. This study represents a significant advancement in optimizing the properties of persistent luminescent materials, where dopants simultaneously serve as emitters and trap centers.

High dielectric energy storage properties of chitin matrix composites regulated by SiO2.

High-performance polymer-based dielectric materials have attracted much attention in the field of energy storage due to high breakdown field strength and low cost. However, partial polymer-based materials are derived from traditional fossil energy derivatives, which are characterized by non-renewable and low dielectric constants, which are not conducive to the improvement of energy storage. In this paper, dissolved chitin through alkali/urea system is composited with SiO2 prepared by electrostatic spinning. The maximum discharge energy density of the fiber composite film reaches 4.34 J cm-3, which is 1.6 times higher than that of the micron particle composite film (2.8 J cm-3) and 1.9 times higher than that of the pure chitin film. The high aspect ratio and low concentration of silica filler effectively improved the breakdown field strength. In addition, the thermal stability was improved. This study paves the way for the application of bio-based materials in high-performance dielectrics.

Mixed matrix membrane formation with porous metal–organic nanomaterials for CO2 capture and separation: A critical review

Due to the increasingly severe global warming trend, the reduction of CO2 emission and carbon capture have attracted growing interest. The separation of CO2 from gas mixtures, especially from point source and the atmosphere, is considered as one of the most important strategies for mitigating climate change. Porous metal–organic nanomaterials (PNMs), including metal-organic frameworks (MOFs) and metal-organic polyhedra (MOPs) have been extensively investigated in the fields of carbon capture, catalysts, sensors, biomedical imaging and gas storage. Their inherent pores, diverse surface function groups and potential modification possiblities make them competitive carbon capture materials. This review will introduce detailed scientific and technological advancements in PNMs and explain their fitness for carbon capture and separation, followed by the fabrication and application of mixed matrix membranes (MMMs) with PNMs. The current challenges appreared and solutions to improve the MMMs’ CO2 separation performance will also be stressed.

Orange peel derived activated carbon supported Ni–Co3O4 as an efficient electrocatalyst for oxygen evolution and reduction reaction in alkaline media

This study focuses on the development of a cost-effective electrocatalyst with excellent activity and stability for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), which is crucial for water electrolysis and fuel cell technologies. Waste orange peel is utilized as a carbon precursor to synthesize biomass-derived activated carbon (OPAC) with a unique three-dimensional sheet-like microstructure. Subsequently, a simple hydrothermal method is employed to modify the OPAC by introducing Ni-doped Co3O4, leading to the formation of a Ni–Co3O4/OPAC hybrid. We propose the Ni–Co3O4/OPAC hybrid as a highly efficient bifunctional electrocatalyst for both OER and ORR. Co3O4/OPAC and Co3O4 catalysts are also prepared for comparison. Remarkably, the Ni–Co3O4/OPAC hybrid exhibits significantly enhanced OER activity compared to Co3O4/OPAC and Co3O4 catalysts. It demonstrates a lower overpotential of 360 mV and a lower Tafel slope of 55.47 mV/dec, indicative of more efficient electrochemical performance. Moreover, in the ORR analysis, the Ni–Co3O4/OPAC hybrid displays a two-step pathway and achieves a higher ORR limiting current density compared to the Co3O4/OPAC and Co3O4 catalysts. These results highlight the synergistic effects of Ni and Co species, along with the unique properties of the OPAC support, which contribute to the enhanced activity, stability, and electron transfer characteristics of the Ni–Co3O4/OPAC hybrid. Furthermore, the improved electrical conductivity of the Ni–Co3O4/OPAC hybrid makes it a promising candidate for applications in metal-air batteries and other energy conversion devices. The utilization of waste orange peel as a carbon precursor and the facile synthesis method demonstrate the potential for cost-effective and sustainable electrocatalyst production. Overall, the Ni–Co3O4/OPAC hybrid represents a significant advancement in electrocatalyst design and holds promise for advancing the field of energy conversion and storage.

Realizing multimodal lithography effects by adjusting laser exposure power ranges for TeOx inorganic photoresist

Abstract Suboxide chalcogenide thin films like TeO x are promising inorganic lithography materials. Different from previous reports of single-mode lithography based on TeO x films at low laser power, this study proposes multimodal lithography effects at low, medium, and high laser power ranges. The TeO x films were fabricated by reactive magnetron sputtering, exhibiting super smooth surface with an RMS 0.33 nm. The lithographic performance was researched using a laser direct writing system with a wavelength of 780 nm. The experiment results showed that different kind of lithographic patterns were achieved by changing laser power ranges. At low exposure powers (5 mW to 9 mW), TeO x film transforms from amorphous to crystalline, generating patterns with single-trench since only the crystalline state dissolves in alkaline developers. At medium exposure powers (10 mW to 15 mW), the center of the laser spot that has greater power turns the film from amorphous to crystalline and then back to amorphous due to the rapid quenching process, while the outer region cools slowly to form crystalline, resulting in the patterns with double-trenches, with feature size 119 nm (about 1/7 λ). At high exposure powers (>16 mW), the laser power is capable of ablating the TeO x film, resulting in the ablation and redeposition patterns. Therefore, multimodal lithographic nano-patterns on the same TeO x photoresist film can be realized with only one lithography process by precisely manipulating the laser power ranges, which has significant implications in the fields of nano-manufacturing and optical storage.

SnO2-TiO2/reduced graphene oxide nanocomposites: Green synthesis and enhanced photocatalytic efficiency for dye removal

Titanium oxide nanoparticles (TiO2 NPs) have been interested in potential applications, including gas-sensing, energy storage, environmental remediation, and medical fields. In the present work, fabricated SnO2-TiO2/RGO nanocomposites (NCs) have been produced through a green precipitation approach. XRD, TEM, SEM, EDX, XPS, FTIR, UV, and PL analyses have been carefully applied to invistage the physicochemical properties of prepared NPs and NCs. The XRD data showed that the crystal structure of the TiO2 NPs was affected by the introduction of SnO2 NPs and RGO sheets. The spherical shape of the prepared samples and their morphologies were confirmed using TEM and SEM images. EDX and XPS analyses confirmed that tin (Sn), titanium (Ti), oxygen (O), and carbon (C) were further present in the SnO2-TiO2/RGO NCs. FT-IR spectra determines the functional groups with bands between the compositions of obtained NPs and NCs. Besides, the band gap energies of prepares samples were estimated from UV–vis spectra. It displayed that the absorption peak of the synthesized TiO2 NPs was improved after the addition of SnO2 NPs and an RGO sheet. PL analysis indicate that the PL intensity of the prepared TiO2 NPs was decreased with the addition of SnO2 NPs and RGO sheets due to a decrease in the recombination rate of electrons (e−)-holes (h+). As shown in photocatalytic results, the photodegradation of methylene blue (MB) dye of SnO2-TiO2/RGO NCs was reached 92.20% after 140 min of UV irradiation. These results suggest that the addition of RGO sheets occupied a role in enhanced the photocatalytic performance of the prepared NCs. This study highlighted that these samples could be applied in various applications such as photocatalytic and therapeutic areas.

Design of a LiF-rich solid electrolyte interphase layer through a fluorinated carbon (CFX) complex separator for stable lithium metal batteries

The formation of a stable solid electrolyte interphase (SEI) layer is very important for improving the cycling stability and safety of lithium metal batteries (LMBs). However, since the reactivity of lithium metal anodes (LMAs) is very high, controlling the movement of Li+ at the anode/electrolyte interface remains challenging. In this study, an approach involving coating a fluorine functional-controlled fluorinated carbon (CFX) layer onto a commercial PE separator to form a stable SEI layer was proposed. The strong reaction between the fluorine functional groups constituting CFX and Li+ facilitated the rapid formation of a LiF-rich SEI layer in the resting and initial cycling stages. This initial stable SEI layer promoted a subsequent homogeneous Li+ flux, thus improving the LMA stability. In addition, the mechanism by which the total amount of fluorine and the fluorine functional groups control the Li+ dynamics through the CFX-coated PE separator with controlled fluorine functional groups was used to identify the mechanism by which the total amount of fluorine and the fluorine functional groups provide the advantage of the creation of a stable SEI layer. Therefore, this study contributes to the energy storage field by solving the cycling stability problem related to LMAs and emphasizes that a stable SEI layer can be formed based on the important interface control according to the type of fluorine functional group.

Carbon sequestration behavior of magnesium oxychloride cement based on salt lakes magnesium residue and industrial solid waste

With the extensive utilization of lithium-ion battery in the electric vehicle and energy storage field, the consumption of lithium has been sharply increasing. Lithium resource occurrence area were facing increasing environmental pressure, particularly the magnesium residue (MR) produced in the lithium extraction process, and a sustainable exploitation pathway have not been established. In the framework of "net-zero", MRs were onverted to Salt lake magnesium oxide (SL-MgO) which was characterized by various elemental and surface analysis methods. Magnesium oxychloride cement (MOC) was prepared form SL-MgO and two industrial solid wastes [fly ash (FA) and phosphogypsum (PG)], and its carbon sequestration capacity was analyzed and evaluated. If all the MRs produced from the lithium extraction process were used to manufacture MOC materials for CO2 sequestration. When the PG content was 20 %, the CO2 sequestration capacity of the MOC was 0.29 kg/m2, the compressive strength was 85.30 MPa, and the MOC neutralized 220.10 % of the CO2 emissions from the lithium extraction process. In this procedure, evidence was found of the typical metastable carbonate products identifiable. Overall, utilizing MRs and industrial solid waste to manufacture new low-carbon MOCs may become the most direct and effective countermeasures to alleviate environmental pressure in these regions.

Preparation of lignite-based porous carbon for high performance supercapacitor and the correlation between pore structures and electrochemical performance

Porous carbon exhibits considerable potential in energy storage field due to its remarkable electrical conductivity and adjustable pore structure. Nevertheless, the electrochemical performance of the material will be significantly impacted by its unreasonable pore structure. In this study, lignite was used as raw material to prepare lignite-based porous carbon by one-step activation method and the pore structure was optimized to improve its electrochemical performance and expand the utilization of low-rank coal. The results reveal that the porous carbon prepared at 600 °C has a higher specific surface area (940 m2 g−1) and a suitable pore structure (71 % mesopore), which enable adequate charge storage and fast transport of electrolyte ions, resulting in excellent electrochemical performance. In the three-electrode system, the lignite-based porous carbon exhibits a notable specific capacity of 331 F g−1 at the current density of 0.5 A g−1 and retains 96.4 % initial capacitance after undergoing 10,000 cycles. When assembled into a symmetrical supercapacitor, the device provides an energy density of 6.5 Wh kg−1 at a power density of 250 W kg−1. Even after 10,000 cycles, the capacitance retention rate is kept at 91 %, and the coulombic efficiency remains close to 100 %. These findings demonstrate that cost-effective porous carbon can be prepared by a simple route using lignite, hence exhibiting promise as electrode materials for high-performance supercapacitors.

Li-decorated 2D Aluminium Phosphide monolayer for hydrogen storage capacity: Insights from DFT computations

This study comprises of a theoretical investigation to evaluate the hydrogen storage capability of Li-decorated N-doped Aluminium Phosphide (AlP) monolayer using DFT. The structural stability of AlP monolayer and its N-doped version is verified using phonon dispersion curves along with molecular dynamic simulations. A light electropositive atom i.e. Li is successfully decorated on its surface to make hydrogen adsorption easier by polarizing them. The adsorption energies are calculated for each adsorbed H2 molecules and each Li was seen to have stored eight H2 molecules with average adsorption energy of -0.2268 eV and -0.2299 eV for pristine AlP and N-doped AlP respectively. Since Li-decorated N-doped AlP showed higher average adsorption energy, therefore four Li atoms are decorated on it and hydrogen storage performance is evaluated. The electronic properties are checked at each step to verify the bonding interactions and charge transfer. Each Li on substrate stored eight H2 molecules making a total of 32 H2 molecules with the gravimetric capacity of 6.54 % which exceeds the target of 5.5 % set by US department of Energy. The desorption temperature revealed its suitability for reversible hydrogen storage making it a strong candidate in the hydrogen storage field.

Preservative for High Antioxidant and Antimicrobial Activity and Low Toxicity.

There is an urgent need for highly efficacious and minimally toxic preservatives for vegetables and fruits to ensure extended freshness and safety. Using natural polymer starch as the matrix, we produced nicotinated starch-ethylamine (NSA) based on N,N'-carbonyldiimidazole (CDI) acting as the catalyst and 2-chloroethylaminehydrochloride as the nucleophile. To strengthen the antimicrobial and antioxidant activity, NSA was reacted with three different cinnamic acids to prepare starch derivatives bearing cinnamyl (CNSA, DNSA, and ENSA). With a grafting rate of 27%, ENSA demonstrated notable antioxidant capability reaching ∼85% at 1.6 mg/mL. Also, it displayed inhibitory indices of 88.14%, 89.11%, and 77.90% against Botrytis cinerea, Phomopsis asparagi, and Glomerella cingulate, respectively, at a concentration of 1.0 mg/mL. The cytotoxicity test showed that the 293T cell survival ratio reached 101.5%. In addition, the sample was able to extend the shelf life of the cherry tomatoes by three days. This study has successfully developed a novel starch-based preservative for fruits and vegetables that not only possesses excellent antioxidant and antimicrobial properties but also effectively extends the shelf life of produce, demonstrating its broad application prospects in the field of fruit and vegetable storage and preservation.

Effect of Rb substitution on dielectric, ferroelectric, mechanical and biocompatibility properties of Na0.2K0.3Bi0.5TiO3 ceramics

This study focuses on the strategically developed Rb-substituted lead-free Na0.2K0.3Bi0.5TiO3 (NKBT) ceramic, highlighting its applications in energy storage, bio-implants, actuators, dielectric capacitors, and various other fields. The significant decrement of average grain size of ∼0.31 μm from ∼0.62 μm has been observed via surface morphology analysis with ultra-high Vickers hardness of ∼8 GPa in Na0.2K0.24Rb0.06Bi0.5TiO3 (RB 6) which is within the range to use bio-implants. The biocompatibility of samples verified cell growth and was monitored using two fluorescence dyes: fluorescein diacetate (FDA for live cell staining) and propidium iodide (PI for dead cell staining) under a fluorescence microscope. Also, the findings reveal that Rb-NKBT exhibits excellent biocompatibility with normal fibroblast cells and possesses impressive mechanical strength. Moreover, The X-ray and Raman inquiry confirms the tetragonal crystal structure of the samples. Frequency-dependent dielectric curve and shifting of Tm reveal the enhanced relaxor property with broadening signifies the increase in thermal stability. It is an important parameter for biological applications, particularly those involving functional temperatures, as the material must remain ferroelectric within the operating temperature range. Furthermore, the higher breakdown strength of ∼110 kV/cm with a recoverable energy storage density of 0.62 J/cm3 was found in the RB 6. The S-ve of the material decreases with the substitution of the Rb, which has been useful for actuator application. This study offers a comprehensive discussion on the utility of NKBT FCs as an active functional material for biomedical applications and dielectric applications with the advantage of non-invasive evaluation for potential failure with their sensing applications.

Flux Synthesis of Robust Polyimide Covalent Organic Frameworks with High-Density Redox Sites for Efficient Proton Batteries.

Aqueous proton batteries are attracting increasing attention in the large-scale next-generation energy storage field. However, the electrode materials for proton batteries often suffer from low specific capacity and unsatisfactory cycle durability. Herein, we synthesize two highly crystalline and robust polyimide covalent organic frameworks (COFs) through a solvent-free flux synthesis approach with benzoic acid as a flux and catalyst. The as-synthesized COFs possess enriched redox-active sites for proton storage and intrinsic Grotthuss proton conduction, rendering them ideal candidates for proton electrode materials. The optimal COF electrodes achieve a high specific capacity of 180 mAh/g at 0.1 A/g, among the highest COF-based proton batteries, and exhibit an outstanding rate capability of up to 100 A/g and long-term cycling stability with capacity retention of 99% after 5000 cycles at 5 A/g. The assembled full cells deliver a specific capacity of 150 mAh/g at 0.2 A/g with a maximum energy density of 72 Wh/kg and a maximum supercapacitor-level power density of 64 kW/kg, surpassing all reported COF-based systems. This work paves a new avenue for the design of electrode materials for aqueous proton batteries with high energy density, power density, rate capability and long-term cycling stability.

High-Performance Flexible and Symmetric Supercapacitors Based on Micro-Flower-Like MnSe@Ti3C2Tx Heterostructure.

Flexible supercapacitors, renowned for their exceptional power density and cycling stability, are a focus in the field of energy storage. Ti3C2Tx MXene is a promising electrode material for supercapacitors owing to its excellent metallic conductivity. However, its stacking layered structure limits device performance on specific capacitance, operating voltage, and energy density. Herein, a MnSe@Ti3C2Tx heterostructure is developed to enhance the electrochemical performance of Ti3C2Tx-based electrode materials. With the solvothermal synthesis method, MnSe nanosheets are in situ grown on Ti3C2Tx surface to form micro-flower-like MnSe@Ti3C2Tx heterostructures by adjusting the ratio of ethanolamine solvent and the amount of Ti3C2Tx. The specific capacitance of the optimized heterostructure (E3/MnSe@Ti3C2Tx-45) is as high as 721.4Fg-1 at 1Ag-1, approximately ten times higher than that of pure Ti3C2Tx. The MnSe@Ti3C2Tx flexible symmetric supercapacitor (MT-FSC) based on E3/MnSe@Ti3C2Tx-45 exhibits a wide working voltage window of 1.2V and a large energy density of 28.68Whkg-1 at 308.23Wkg-1. The capacitance retention rate keeps 90.77% after 4000 charge-discharge cycles. Furthermore, MT-FSC can power LEDs even under large-angle (90°) bending. This heterostructure electrode material not only improves the electrochemical performance of Ti3C2Tx-based flexible supercapacitors but also offers a robust energy supply for flexible wearable electronic devices.