MXenes have emerged as a pivotal class of two-dimensional materials driving the evolution of rechargeable battery technologies from conventional aqueous systems toward advanced solid-state architectures. Their exceptional electrical conductivity, lamellar framework, and chemically tunable surface terminations enable precise control over charge transport, ion storage, and interfacial reactions. This review critically surveys recent advances in MXene-based batteries, highlighting their functional roles across aqueous and solid-state energy storage platforms. In aqueous batteries, MXenes facilitate rapid redox kinetics, high-rate capability, and enhanced electrochemical stability through optimized surface chemistry and electrolyte compatibility. As battery technologies transition toward solid-state configurations, MXenes emerge as conductive interlayers, ion-transport facilitators, and interface-stabilizing components that mitigate contact resistance and mechanical mismatch between electrodes and solid electrolytes.The review also focuses on key challenges, such as oxidation susceptibility, harsh synthesis routes, and scalability of synthesis. By mapping the evolutionary trajectory of MXene integration from aqueous to solid-state batteries, this review provides a forward-looking framework for leveraging MXenes in next-generation, high-performance, and environmentally responsible energy storage technologies.

Solid-state batteries (SSBs) are emerging as a transformative solution for high-energy-density and intrinsically safe energy storage systems. Challenges, such as low ionic conductivity, poor interfacial contact, and lithium dendrite formation, continue to impede their large-scale adoption despite significant advances in electrochemical stability, thermal resilience, and compact cell design. MXenes are a novel family of 2D transition metal carbides and nitrides that have shown great promise to overcome these limitations due to their tunable surface terminations, high conductivity, and structural versatility. This review explores the recent breakthroughs in MXene-integrated all SSBs. It delves into their roles as functional fillers in solid-state electrolytes (SSEs) as well as interfacial layers, electrodes, and current collectors. We discuss synthesis strategies, surface engineering, and design principles that enable MXenes to enhance ionic transport, suppress dendrite growth, and improve interfacial compatibility. A foundational overview of MXene physicochemical properties that are relevant to SSBs is provided in addition to an evaluation of the key SSE characteristics. Finally, the review outlines critical challenges and future directions for the rational design of MXene-enabled SSB architectures. This review aims to accelerate the development of safe, durable, and high-performance SSBs by bridging a fundamental understanding with application-driven innovation.

This study demonstrates that N and Co co-doped MXene, with tuned doping levels, alters electrochemical performance, where the synergistic heteroatom incorporation improves capacitance, charge transport, and the HER activity.

MXene-based materials have attracted significant attention as next-generation electrode materials for supercapacitors due to their metallic conductivity, tunable surface chemistry, and high volumetric capacitance. However, their electrochemical performance is often limited by nanosheet restacking and sluggish ion transport, which restricts access to the active surface. To address these limitations, a Ti3C2Tx MXene-based ternary composite incorporating intercalated carbon nanotubes (CNTs) and tungsten oxide (WO3) nanostructures (MX-CNT-WO3) was developed, and the CNT and WO3 contents were systematically optimized (3, 5, and 7 wt%) to achieve enhanced charge-storage performance. CNTs incorporation prevents MXene restacking, exposes basal planes for ion access, and forms conductive networks that accelerate electron transport, thereby enhancing rate capability. Meanwhile, the inclusion of WO3 introduces additional redox-active sites and expands the interlayer spacing, improving ion accessibility and overall charge storage capacity. Electrochemical evaluation in 1 M H2SO4 electrolyte demonstrated that the MX-CNT-WO3 (5 wt%) electrode achieved a specific capacitance of similar to 320 F g(-1), significantly higher than pristine MXene (similar to 229 F g(-1)), with better rate capability and capacitive retention even at high scan rates. The hybrid electrode also delivered an energy density of similar to 12 Wh kg(-1) at a power density of 7.3 kW kg(-1), highlighting the synergistic effects of CNT and WO3 intercalation. The MX-CNT-WO3 electrode-based device retains similar to 80% capacitance after 10,000 cycles at 10 A g(-1) with similar to 100% coulombic efficiency, indicating good reversibility despite minor structural degradation.

This work investigates the structural and electronic characteristics of the WS2/4H-SiC heterostructure through first-principles calculations using density functional theory (DFT). To obtain reliable bandgap values, the hybrid HSE06 functional along with norm-conserving pseudopotentials was employed. The computational setup included a plane-wave cutoff energy of 500 eV and a 5 & times; 5 & times; 1 Monkhorst-Pack k-point grid for Brillouin zone (BZ) integration. Full structural relaxation yielded lattice constants of a = b = 3.065 & Aring; and c = 22.99 & Aring;, with interaxial angles alpha = beta = 90 degrees and gamma = 120 degrees, confirming a stable layered hexagonal configuration. The electronic band structure displays an indirect gap of similar to 40.2 meV, indicative of semi-metallic behavior. The projected density of states (PDOS) reveals the orbital hybridization between WS2 and SiC, particularly near the Fermi level. Therefore, the WS2/4H-SiC interface demonstrates strong electronic interaction, making it a viable material platform for next-generation nanoelectronics and high-performance power devices.

Ti 3 C 2 T x MXene possesses remarkable properties for energy storage and electrocatalysis, yet its limited active sites and moderate catalytic activity restrict performance. This study explores nitrogen (N) and cobalt (Co) co‐doping of Ti 3 C 2 T x MXene (MX–N–Co) as a strategy to enhance functionality, systematically comparing it with pristine and individually doped Ti 3 C 2 T x MXene with N and Co (MX–N, MX–Co) to elucidate the synergistic effects of dual doping on electrochemical capacitance and catalytic efficiency. Electrochemical characterizations reveal that the specific capacitance follows the order: MX–N–Co > MX–Co > MX > MX–N, whereas the hydrogen evolution reaction (HER) activity order is: MX–N–Co > MX–Co > MX–N > MX. N doping introduces lone pairs and modulates the electronic structure, enhancing HER kinetics but potentially degrading capacitance due to excessive defects and hindered ion diffusion. Co incorporation improves electrical conductivity and adds catalytic centers. Additionally, the MX–N–Co co‐doped electrode exhibits ≈25% higher capacitance than pristine Ti 3 C 2 T x MXene and superior HER activity, delivering a Tafel slope of 94 mV dec −1 and an overpotential of 243 mV at 10 mA cm − 2 , compared to 113 mV dec −1 and 290 mV at 10 mA cm − 2 for the pristine counterpart.

MXenes are known for their exceptionally high electrical conductivity, mechanical resilience, and versatile surface chemistry. However, these tend to oxidize under ambient conditions, posing a major hurdle in their performance...

Recent advances in various engineering applications demand new materials that have multi-functionality along with suitable structural properties. Metal matrix composites are the class of materials that satisfy this purpose due to their lightweight, increased strength, and other improved mechanical properties. These composite materials can be prepared by various conventional techniques which aim reducing the cost of production and meeting the demand of the industries efficiently. The properties and functionality of these materials are greatly influenced by the type of reinforced particulates and their composition in the metal matrix. Many reinforcement particles or fibers can be used in MMC depending upon the applications. Commonly used reinforced materials are graphene, polymers, carbon fibers, ceramic materials, etc. Among the carbon family, carbon nanotubes (CNT) exhibit enhanced performance as an ideal reinforcement material for MMCs. With outstanding intrinsic physical properties, CNTs are considered a promising candidate for reinforcement. CNT owes its properties due to its small diameter, high tensile strength, stiffness, high Young’s modulus, and good chemical stability. They exhibit thermal stability even at high temperatures and exhibit good electrical conductivity. They also show improved fatigue resistance and plasticity and thus broaden the performance of the MMC. In this chapter, various fabrication techniques along with blending and processing methods of CNT-reinforced MMC have been discussed. The main methods have been explained with their schematic representations. The advantages and limitations of these methods have also been discussed. A strong interfacial bonding between the reinforced particulate and the metal matrix affects the performance of the material. This chapter also deals with a deep understanding of the various interfacial bonds that can exist between CNT and the metal matrix

Due to their distinguished electrical conductivity and mechanical flexibility, MXenes have emerged as fundamental nanomaterials in the development of various kinds of devices. These attributes position MXenes ahead of other 2D materials, such as graphene, in the fabrication of a wide array of flexible devices. Ease of synthesis and transparency add another feather to MXenes’ wings, enhancing their versatility. This review emphasizes the unique structural, mechanical characteristics, electrical, and surface characteristics of MXenes, tailored for the development of diverse flexible devices. The role of MXenes in a variety of flexible device applications, ranging from energy storage solutions such as supercapacitors, batteries, solar cells, flexible sensors, EMI shielding, electronic skins (e-skin), self-powered systems, transparent conductive electrodes (TCE), flexible displays, etc., has been explored. The review highlights the contribution of MXenes in improving the durability and efficiency of flexible electronics, thereby enhancing their operational lifespan. The use of MXenes in wearable and flexible devices has been explored to showcase their potential in advancing the design and manufacturing of these devices. MXene-based materials stand out not only for their exceptional performance but also for their role in driving forward novel applications, signifying a major shift in flexible electronics.The review provides essential insights into MXenes-based flexible device development, offering a framework for future advancements in the field of flexible devices.

Transparent conducting oxides (TCOs) have emerged as reliable electrode materials for use in organic light-emitting diodes (OLEDs) owing to their remarkable optoelectronic properties such as excellent electrical conductivity, low sheet resistance, and high optical transparency in the visible region. The fundamental structure, operating principle, and generations of OLEDs have all been thoroughly discussed. The main deposition techniques and the desirable properties of TCOs are also discussed. As an alternative to indium tin oxide (ITO), the researchers investigated various promising TCOs with advantages and insurmountable problems limiting their widespread use at the industrial level. To improve the optoelectronic performance of TCOs and thus OLEDs, researchers and scientists have used various strategies such as doping, multicomponent structures, multilayered structures, surface treatments, and thin film thickness variation.

The present study examined potential benefits of heteroatom doping to manipulate the electrical structure and to enhance the efficiency of the sensor, with an emphasis on developing inexpensive, metal-free electrochemical sensors. Melamine and ammonium oxalate were used as precursors in a one-step thermal polymerization technique yielding oxygen-doped graphitic carbon nitride (O-gCN). Following synthesis, the material's structural and morphological properties were thoroughly examined using a multitude of analytical techniques, including EIS. A notable decrease in impedance was observed, suggesting improved conductivity. Additionally, the doping approach exhibited a noticeable improvement in reduction current receptivity and surface area as compared to unmodified graphitic carbon nitride (g-CN). Utilizing both differential pulse voltammetry (DPV) and the classical cyclic voltammetry (CV) methods, we investigated the electro oxidation of uric acid (UA) as well as concentration dependence and selectivity studies using oxygen-doped graphitic carbon nitride modified glassy carbon electrode (O-gCN@GCE). O-gCN@GCE demonstrated remarkable performance, allowing the detection of UA concentrations as low as 7.784 mu A mu M(-1)cm(-2). Its low detection limit of 0.57 mu M and wider linear range (5-120 mu M) further highlighted its potential for extremely sensitive assays and its remarkable capacity to operate over a broad UA concentration range.

In this study, cupric oxide (CuO) nanoparticles (NPs) were synthesized using copper chloride and different concentrations of sodium hydroxide in an aqueous medium without the use of a surfactant or template. The crystal structure, purity, crystallite size, intrinsic strain, stress, and elastic energy of the as-synthesized samples were all determined using x-ray diffraction (XRD). CuO nanoparticles were confirmed to have a monoclinic structure through XRD analysis. From the XRD peak broadening analysis, the crystallite size and intrinsic strain were investigated using the Williamson–Hall plot (WHP), size–strain plot (SSP), and Halder–Wagner (HW) method. To determine physical and micro-structural parameters such as strain, stress, and energy density, the WHP used three different models: the uniform deformation model (UDM), the uniform stress deformation model (USDM), and uniform deformation energy density model (UDEDM). Field-emission scanning electron microscopy (FE-SEM) micrographs revealed leaf-like, flower-like, and network-like morphologies. At room temperature, the optical properties of the CuO NPs were investigated using ultraviolet-visible (UV–Vis) and photoluminescence (PL) spectroscopy. Using Tauc's plot, the estimated optical energy bandgap ( E g ) was 3.70–3.80 eV. CuO nano-leaves had a strong green emission peak at 504 nm and a less intense emission peak at 757 nm.

Objective: In the present study, cupric sulfide (CuS) nanoparticles (NPs) were synthesized in deionized (DIW) water using an eco-benign, simple, and cost-effective chemical route that requires no surfactant or template. Methods: Polypyrrole/cupric sulfide (PPy/CuS) hybrid nanocomposite (HNC) was synthesized using an in-situ chemical oxidative polymerization method in the presence of obtained CuS NPs. The X-ray diffraction (XRD) analysis confirmed the hexagonal structure of CuS, whose crystalline nature was preserved in the HNC. For CuS NPs and PPy/CuS HNC, elastic properties, such as intrinsic microstrain, internal stress, dislocation density, strain energy density, stacking faults, and intercrystalline separation, were used to analyze the crystal imperfections and distortions. Results: Field emission scanning electron spectroscopy (FESEM) micrographs revealed that CuS NPs and PPy/CuS HNC have particulate and globular morphology, respectively. The values of the average intrinsic strain, dislocation density, internal stresses, and strain energy density of PPy/CuS HNC were estimated to be ~2 × 10-3, ~8.8166 × 1015 m-2, 164.263 MPa, and 127.278 KJ m−3, respectively, which were observed to be higher than those of CuS NPs. Conclusion: The DC electrical conductivity of as-synthesized samples was measured at room temperature in pelletized form, using the standard four-probe method, and conductivity values were estimated to be ~480 Scm-1 and ~4 Scm-1 for CuS NPs and PPy/CuS HNC, respectively.

This study investigates the structural and optical properties of doped CuI nanocrystals synthesized using a facile chemical method. Cadmium (Cd) and iron (Fe) were used as dopants, resulting in CuI-Cd and CuI-Fe samples. Xray diffraction (XRD) was employed to characterize the crystal structure and phase purity. Rietveld refinement of the XRD data provided significant refinement parameters. The Williamson-Hall and Size-strain methods were applied for further analysis, yielding consistent size and strain values. X-ray photoelectron spectroscopy (XPS) was utilized to investigate the electronic states and dopant incorporation in CuI nanocrystals. The undoped and doped CuI samples exhibited distinctive morphologies, with pure CuI displaying an irregular shape, CuI-Cd showcasing a hexagonal morphology, and CuI-Fe featuring a triangular morphology. The average crystallite sizes of the nanocrystals were determined to be 96.67 nm, 70.57 nm, and 54.10 nm for pure CuI, CuI-Cd, and CuI-Fe, respectively. Energy-dispersive X-ray (EDX) analysis confirmed the presence of Cd and Fe in the doped samples. Optical bandgap energies estimated using Tauc's plot were 4.1 eV (CuI), 4.0 eV (CuI-Cd), and 4.0 eV (CuI-Fe).

Polypyrrole has a unique place among conducting polymers discovered so far, due to its advantageous properties such as low-cost synthesis, stable electrical conductivity, non-toxicity, environmentally benign nature, etc. In this study, the polymerization of polypyrrole is carried out inside the porous structure of the polyvinylidene fluoride (PVDF) matrix using the chemical oxidation method to prepare flexible and rollable conducting films. The resistivity measurement of these flexible and rollable Polypyrrole-PVDF films were carried out using a standard four-point probe method in the temperature range of 320–10 K. The room temperature dc electrical conductivity of the film was found to be ∼ 50 S/m. To understand the charge transport mechanism in these films the experimental data were analyzed in the light of Mott’s variable range hopping model and Fluctuation assisted tunneling model. It was found that experimental data follows the three-dimensional variable range hopping behavior from 320 K to 90 K and below 90 K a crossover from hopping to fluctuation-assisted tunneling was observed. Mott’s parameters were measured in the temperature range of 320–90 K and the corresponding values for density of states at the Fermi level N(EF), average hopping distance (R), and average hopping energy (W) were found to be 5.54 × 1029 m-3eV−1, 2.94 Å and 17.7 meV respectively.

In this study, polypyrrole cuprous iodide (PPy-CuI) hybrid nanocomposites were synthesized in an aqueous medium via an in-situ chemical oxidation route with ammonium persulphate as an oxidizing agent to report the microstructural, morphological, and electrical properties of as-synthesized specimens. By using an in-situ oxidative polymerization method, sonochemically synthesized gamma-CuI nanocrystals were mixed with a PPy matrix in varying weight percentages (10-40 %). The purity, crystallinity and structure of hybrid nanocomposites were determined using X-ray diffractometry. The average crystallite size of hybrid nanocomposites was calculated using the DebyeScherrer, Williamson-Hall and Size-Strain plot methods. All specimens' intrinsic strain was estimated using the Williamson-Hall plot and the Size-Strain plot methods. The field emission scanning microscopy revealed that the surface morphology changed from granular to overgrown clusters as the weight percent of CuI nanocrystals is increased from 10 to 40 % in PPy-CuI hybrid nanocomposites. The Fourier transform infrared spectroscopy indicates the formation of PPy and successful insertion of gamma-CuI nanocrystals into the PPy matrix. The room temperature dc electrical conductivity is found to decrease from 6.3 x 10(-2) Scm(-1) to 1.70 x 10(-3)Scm(-1)as the wt% of.-CuI nanocrystals increases from 10 to 40 % in hybrid nanocomposites. Furthermore, the increasing trend of dc conductivity with temperature is due to all samples' semiconducting nature. In the temperature range of 200-300 K, the measured experimental data followed the Arrhenius and Mott's 3d variable range hopping (VRH) model. The values of average activation energy, average hopping energy, density of states at Fermi level, average hopping distance and Mott's characteristic temperature of PPy-CuI (40 %) hybrid nanocomposites at 300 K were estimated to be similar to 60 meV, similar to 29 meV, 6.36 x 10(22) cm(-3)eV(-1), 5.06 angstrom and 1901 K, respectively.

In this study, we reported facile sonochemical synthesis of CuS nanoparticles by using CuCl2 and Na2S in aqueous medium without using any organic solvent and surfactant. Structural characterization of synthesized product using X-ray diffraction study revealed the formation of hexagonal structure of CuS in covellite phase. Crystallite size of ~13 and ~11 nm were determined using Debye–Scherrer and Williamson–Hall methods, respectively. Field emission scanning electron microscopy micrographs revealed the particulate morphology of CuS nanostructures. The optical properties of CuS nanoparticles were investigated by ultra violet and visible (UV-Vis), photoluminescence (PL), and Fourier transform infrared spectroscopy. The band gap was calculated by Tauc’s relation and found to be 3 eV. The PL spectrum showed a strong green emission at wavelength 505 nm. The electrical conductivity of CuS nanoparticles was found to be in semiconducting range, i.e. 550 S/cm. Impedance analysis of CuS nanoparticles revealed 7.55 MHz as the resonant frequency.