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In this study, a novel multiscale carbon architecture was developed by integrating mesocarbon microbeads (MCMBs), graphitic nanofibers (GNFs), and mesoporous carbon, aimed at enhancing the performance of symmetric supercapacitors. The unique combination of spherical MCMB particles, conductive GNF nanofibers, and mesoporous carbon sheets resulted in a highly effective electrode material, offering improved conductivity, increased active sites for charge storage, and enhanced structural stability. The fabricated MCMB/GNF/MC architecture demonstrated a remarkable specific capacitance of 393 F g−1 at 1 A g−1 in a three-electrode system, significantly surpassing the performance of individual MCMBs and MCMB/GNF electrodes. Furthermore, the architecture was incorporated into a symmetric supercapacitor (SSC) device, where it achieved a capacitance of 86 F g−1 at 1 A g−1. The device exhibited excellent cycling stability, retaining 92% of its initial capacitance after 10,000 charge–discharge cycles, with an outstanding coulombic efficiency of 99%. At optimal operating conditions, the SSC device delivered an energy density of 11 Wh kg−1 at a power density of 500 W kg−1, making it a promising candidate for high-performance energy-storage applications. This multiscale carbon architecture represents a significant advancement in the design of electrode materials for symmetric supercapacitors, offering a balance of high energy and power density, long-term stability, and excellent scalability for practical applications. This work not only contributes to the development of high-performance electrode materials but also paves the way for scalable, long-lasting supercapacitors for future energy-storage technologies. [ABSTRACT FROM AUTHOR]

Increasing concerns about the vulnerability of the world’s energy supply and the necessity to implement sustainable technologies have prompted researchers to develop high-performance electrocatalysts that are affordable and efficient for converting and storing renewable energy. This article reports a facile approach to fabricating two-dimensional (2D) Ge-decorated h-BN/MoS2 heterostructure nanosheets by self-assembly for multiple electrochemical applications such as supercapacitor and hydrogen evolution reactions. The organization of the physical and chemical links between the germanium modulations on the heterostructure of boron nitride/molybdenum sulphide (Ge/h-BN/MoS2) were facilitated to generate more active sites. Furthermore, the asymmetric supercapacitor of Ge-decorated h-BN/MoS2 amplified the capacitance to 558.53 F g−1 at 1 A g−1 current density and 159.19 F g−1 at 10 A g−1, in addition to a retention rate of 85.69% after 2000 cycles. Moreover, the Ge-decorated h-BN/MoS2 catalyst realized a low over-potential value, with an RHE of 0.57 (HER) at 5 mA/cm2, a Tafel value of ∼204 mV/dec, and long-term electrolysis stability of 10 h. This work may open the door for further investigations on metal-decorated heterostructures, which have a significant potential for both supercapacitor and water-splitting applications.

This manuscript presents a novel method to enhance the electrochemical performance of CaMoO4 for supercapacitors by synthesizing it from a bi-metallic metal–organic framework (MOF). The resulting CaMoO4 nanoparticles retain MOF characteristics, with a high surface area, and demonstrate improved performance over conventionally synthesized CaMoO4. Electrochemical tests showed the MOF-derived CaMoO4 achieved a high capacitance of 377.82 F g−1 at 1 A g−1 and retained 91% of its capacitance after 5000 cycles. The assembled asymmetric supercapacitor also retained 88% of its capacitance after 10 000 cycles, highlighting the potential of this approach for enhancing energy storage devices. [ABSTRACT FROM AUTHOR]

Designing and developing high‐efficiency multifunctional catalysts materials is a significant challenge. In this view, we synthesized Graphene Quantum Dots (gQDs)/Gadolinium Manganese Oxide (GMO) nanostructures for photocatalytic dye degradation and hydrogen peroxide sensing. The structural, optical, composition, and morphology properties of the gQDs/GMO nanostructures were analyzed by using various analytical tools. The gQDs/GMO catalyst shows higher degradation efficiency compared to pure catalysts under visible light irradiation which is due to the large surface area, lower band gap, small amount of hydrogen peroxide (H2O2), and synergetic effect of gQDs/GMO. Furthermore, we extensively investigate the nonenzymatic H2O2 sensing and the gQDs/GMO catalytic materials show higher sensing behavior. From our results, the gQDs embedded in gadolinium‐modified manganese oxide (gQDs/GMO) serve as an efficient photocatalyst material for environmental pollutant degradation under visible light irradiation with and the sensitive electrocatalyst for nonenzymatic H2O2 sensing applications. [ABSTRACT FROM AUTHOR]

A metal oxide consisting of calcium and manganese (CaMn3O6) in a spherical architecture was successfully prepared by a simple hydrothermal method. Subsequently, Ipomoea carnea-derived carbon (IC) was synthesized and a nanocomposite with CaMn3O6 was formed. The pure CaMn3O6 exhibited a higher surface area of 111 m2 g−1 and CaMn3O6/IC showed a surface area of 101 m2 g−1 with enhanced pore volume, which was desirable in delivering better capacitance. The electrode materials were tested in both three-electrode and two-electrode systems in which CaMn3O6 delivered a capacitance of 294 F g−1 and CaMn3O6/IC delivered a capacitance of 414 F g−1. Furthermore, on fabricating a pouch-cell type asymmetric supercapacitor, CaMn3O6‖AC device showed a capacitance of 76 F g−1 and CaMn3O6/IC‖AC device delivered a capacitance of 116 F g−1. In addition, the CaMn3O6/IC‖AC device showed superior stability and capacitance retention, which can be associated with the presence of an IC matrix. Utilizing the CaMn3O6/IC‖AC pouch-cell device, an LED bulb was operated to test for real-time applications. [ABSTRACT FROM AUTHOR]

Lithium iron orthosilicate (LFS) cathode can be prepared via the polyol-assisted ball milling method with the incorporation of carbon derived from eggshell membrane (ESM) for improving inherent poor electronic conduction. The powder X-ray diffraction (XRD) pattern confirmed the diffraction peaks without any presence of further impure phase. Overall, 9 wt.% of carbon was loaded on the LFS, which was identified using thermogravimetric analysis. The nature of carbon was described using parameters such as monolayer, and average surface area was 53.5 and 24 m2 g−1 with the aid of Langmuir and Brunauer−Emmett−Teller (BET) surface area respectively. The binding energy was observed at 285.66 eV for C−N owing to the nitrogen content in eggshell membrane, which provides more charge carriers for conduction. Transmission electron microscopy (TEM) images clearly show the carbon coating on the LFS, the porous nature of carbon, and the atom arrangements. From the cyclic voltammetry (CV) curve, the ratio of the anodic to the cathodic peak current was calculated as 1.03, which reveals that the materials possess good reversibility. Due to the reversibility of the redox mechanism, the material exhibits discharge specific capacity of 194 mAh g−1 for the first cycle, with capacity retention and an average coulombic efficiency of 94.7% and 98.5% up to 50 cycles.

The great interest in developing emerging zinc-ion capacitors (ZIC) for energy storage applications is due to their inexpensiveness and the future necessity for hybrid electrical energy storage devices. The Zn-ion hybrid capacitor device was assembled using boron (B)-doped reduced graphene oxide (B-RGO) material, which acts as the cathode, and pure zinc metal as an anode. This research work aims to study the influence of B-doped reduced graphene oxide (B-RGO) with Aloe vera gel as an electrolyte. The reduced graphene oxide (RGO) and B-RGO electrode active materials were confirmed through X-ray diffraction (XRD), RAMAN, Fourier transformation infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and field emission-transmission electron microscopy (FE-TEM) analysis. The surface morphological images reveal that a few-layered nanostructure B-RGO was used in the Zn-ion hybrid capacitor device. The electrochemical performance of the Zn-ion hybrid capacitor was evaluated through cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) measurements, with a wide active potential range of 0–2 V versus Zn/Zn+. The mixture composition of Aloe vera extract and 1M ZnSO4 electrolyte generated a stable voltage and exhibited good capacitive behavior. The fabricated ZIC coin cell device with the Aloe vera gel semi-gel electrolyte containing ZnSO4 demonstrated improved Zn+ ionic exchange and storage efficiency. Moreover, the B-RGO electrode active material exhibited excellent cycle stability. The simple one-step electrochemical technique is the most suitable process for boron doping into graphene nanosheets for future energy storage applications. [ABSTRACT FROM AUTHOR]

Poly(styrene‐co‐methylmethacrylate) P(S‐MMA) composite polymer electrolytes are having massive consideration for solid‐state electrochemical devices. There are numerous tactics implement to improve the ambient temperature ionic conductivity such as the addition of plasticizers, the inclusion of nanosize ceramic fillers and blending with the host polymer, which were carried out in this work. The effect of CeO2 on the P(S‐MMA)‐poly(vinylidene fluoride) (25:75 of 27 wt%)‐LiClO4 (8 wt%)‐ethylene carbonate:propylene carbonate (1:1 of 65 wt%) system prepared via a conventional solution casting technique. The as‐prepared polymer membranes were characterized using XRD, Fourier transform infrared spectroscopy, thermogravimetry and differential thermal analysis, SEM and AC impedance analyses. The composite polymer blend gel electrolyte system exhibits high ionic conductivity (2.51 × 10−2 S cm−1) with 6 wt% CeO2 nanofiller at ambient temperature. The conductivity enhancement is due to the presence of a rise in the amorphous content; it is in well concurrence with the XRD results. The optimum electrolyte was used to design the LiFePO4/composite gel polymer electrolyte/Li cell couple in a 2032 type coin cell. It possesses a discharge capacity of 151 mA h g−1 at 0.1 C. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Zirconium oxide (ZrO2) filler is successfully synthesized with spherical morphology (particle size 170 nm) by co‐precipitation technique earlier. The as‐prepared ZrO2 ‐(bare, 3, 6, 9, and 12 wt%) is spread into the augmented poly(styrene‐co‐ methyl methacrylate) P(S‐MMA)‐ poly vinylidene fluoride (PVdF) (25:75 of 27 wt%)‐LiClO4 (8 wt%)‐ ethylene carbonate and propylene carbonate (EC + PC) (1: 1 of 65 wt%) system. The solution casting technique is employed throughout the process. The structural, morphology, thermal and ionic conducting behavior of sample are examined. The highest conductivity is 1.2 × 10−2 S cm−1 at 303 K for P(S‐MMA)‐PVdF (25:75 of 27 wt%) LiClO4 (8 wt%)‐ EC + PC (65 wt%) +6 wt% ZrO2 system. The linear sweep voltammetry and the cyclic voltammetry tests are performed and the results are discussed. The optimized electrolyte is used to make the LiFePO4/CGPE/Li confined 2032 coin cell couple. It holds the discharge capacity of 144 mAh g−1 at rate of 0.1 C with 88% coulombic efficiency. [ABSTRACT FROM AUTHOR]

Summary: Lithium‐sulfur (Li‐S) batteries are deliberated as capable candidate in next generation of rechargeable batteries. It offers a significant specific capacity of 1675 mAh/g and high‐energy density (2600 Wh/kg). In this work, sulfur/MnO2/graphene oxide (GO) composite has been prepared by incorporating sulfur in different ratios with MnO2 and GO (10:20 and 20:10; SMG1 and SMG2) by solid state reaction and used as cathode for Li‐S battery. The obtained composites have been characterized for physical and electrochemical performances. The XRD spectrum display the sulfur is in orthorhombic structure and the presence of carbon has been confirmed by Raman analysis. The SMG2 composite with 70 wt% of sulfur displays a considerably embellished cycling performance (1610 mAh/g at an initial cycle at 0.1 C). The capacity and stability of the material is achieved by suppressing the polysulfides effectively. Low capacity fade, accommodation of volume change arising during cycling processes makes this positive electrode material competent for Li‐S battery application. [ABSTRACT FROM AUTHOR]

In this study, dye/polymer matrix-stabilized β-FeOOH nanomaterials were fabricated for therapeutic applications. Rh-B/F127@β-FeOOH nanomaterials were synthesized using two different methods: co-precipitation (CoP) and hydrothermal (HT) methods. The as-synthesized nanoparticles were characterized using various spectroscopic techniques, including FT-IR, UV-Vis, PL, XRD, HR-TEM, and XPS analysis. The functional groups and optical properties were confirmed by FT-IR spectroscopy, UV-Vis and fluorescence spectroscopy. The Rh-B/F127@β-FeOOH nanomaterials exhibited both rod-like and sphere-like morphology, as confirmed by HR-TEM analysis. Unlike the nanorods, the nanospheres produced multi-colored emissions at 407, 446, 482 and 520 nm. The oxidative states and elements were confirmed by XPS spectroscopy. MTT assays were used to analyze the cytotoxicity of the nanospheres against A549 cells. The reactive oxygen species (ROS) generation and apoptotic cell death caused by the β-FeOOH nanospheres were evaluated by flow cytometry. Cell cycle analysis indicated that the treatment of nanospheres-induced S-phase cell cycle arrest in A549 cells. The synthesized nanospheres induced late-stage apoptosis in the A549 cell line, with a cell death rate of up to 30.37% at the IC 50 concentration. Additionally, the antioxidant activities of the synthesized nanorods showed a high scavenging activity against free radicals, as examined by different assays such as such as DPPH, RP, and FRAP. The above results suggest that the synthesized nanorods and nanospheres are promising and efficient material for therapeutic applications., Competing Interests: We declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)