Advanced Fabrication Techniques Research Articles

Design and application of inertia switch with the zero-time trigger sensor for projectile overload impulse

The paper introduces a novel inertial trigger sensor featuring a multi-layer stacked single-arm brass beam pendulum, aimed at applications in automotive and aerospace fields, etc. It employs the Lagrangian equation for dynamic modeling and finite element analysis to achieve precise inertia force measurements. The design incorporates advanced fabrication techniques and a high-precision latching mechanism that combines circuit self-locking with mechanical triggering. Validated through simulations and testing, The results of the live ammunition tests indicate that, apart from failures of the Inertia Switch due to errors in the manufacturing process, all other inertial switches functioned normally. This demonstrates that the inertial sensor provides an adjustable trigger time of 0–5 ms and reliably withstands extreme overloads of up to 15000 g. This work significantly enhances the performance of inertial sensors in high-stress environments.

Optimization of high-entropy alloys (HEAS) for lightweight automotive components: Design, fabrication, and performance enhancement

This paper provides a comprehensive analysis of the integration and optimization of High-Entropy Alloys (HEAs) for automotive applications, emphasizing their potential to enhance vehicle performance through superior strength-to-weight ratios, thermal stability, and corrosion resistance. Drawing on methodologies from life cycle assessments (LCAs) and insights into fuel savings achieved through lightweight design, the study explores the criteria for selecting HEAs, including composition design, thermal stability, and manufacturing compatibility. It highlights the importance of advanced Computer-Aided Design (CAD) and simulation techniques in optimizing HEA components, ensuring they meet the rigorous demands of automotive applications. The paper also examines fabrication techniques such as arc melting, casting, and additive manufacturing, alongside quality control methods like Non-Destructive Testing (NDT) and mechanical performance assessments. Through case studies of HEA-based engine, structural, and safety components, the research demonstrates significant improvements in fuel efficiency, structural integrity, and safety. The discussion extends to future research directions, focusing on cost reduction, new applications in aerospace and defense, and advancements in fabrication techniques. Finally, the paper addresses sustainability considerations, including resource efficiency, recycling, and life cycle analysis, underscoring the potential of HEAs to contribute to both performance enhancement and environmental conservation in the automotive industry.

Fabrication of high-performance biomedical rare-earth magnesium alloy-based WE43/hydroxyapatite composites through multi-pass friction stir processing

Magnesium-based composites with bioactive ceramic particles addition are promising materials for biomedical implant applications. Nevertheless, the agglomeration of bioactive ceramic particles remains a challenge for fabricating high-performance biomedical magnesium-based composites. Herein, a novel high-performance biomedical rare-earth magnesium alloy-based WE43/hydroxyapatite (HA) composite is successfully fabricated via multi-pass friction stir processing (MP-FSP). Systematic investigations reveal that MP-FSP leads to a uniform distribution of HA particles and efficient elimination of defects. The microstructural analysis shows a significant grain refinement in the WE43 alloy from 49.4 μm to 2.4 μm under triple-passes FSP. The mechanical properties of the composite are enhanced significantly under triple-passes FSP, with yield strength, ultimate tensile strength, and elongation reaching 236.2 MPa, 278.6 MPa, and 14.2% respectively. Corrosion resistance is also improved, with a 30% reduction in the corrosion rate in SBF solution compared to the unprocessed alloy. Moreover, the MP-FSP fabricated composites exhibit superior corrosion-wear resistance, characterized by slight abrasive wear compared to the abrasive wear and severe pitting corrosion observed in the base WE43 alloy. These improvements are attributed to the synergistic effects of grain refinement, dispersion strengthening, enhanced interfacial bonding, and texture modification. Overall, these findings provide significant quantitative insights into the advanced fabrication techniques of magnesium-based composites for biomedical implant applications, highlighting the effectiveness of MP-FSP in enhancing both mechanical and corrosion-related properties.

Nanoenergetic Materials: From Materials to Applications.

Both nanoscience and nanotechnology have undoubtedly contributed significantly to the development of thermite-based nanoenergetic materials (NEMs) with tunable and tailorable combustion performance and their subsequent integration into devices. Specifically, this review article reflects the immense paybacks in designing and fabricating ordered/disordered assembly of energetic materials over multiple length scales (from nano- to milli-scales) in terms of realization of desired reaction rates and sensitivity. Besides presenting a critical review of present advancements made in the synthesis of NEMs, this article touches upon aspects related to various applications concomitantly. The article concludes with the author's summary of the insurmountable challenges and the road ahead toward the deployment of nanoenergetic materials in practical applications. The real challenge lies in the ability to preserve the self-assembly of fuel and oxidizer nanoparticles achieved at the nanoscale while synthesizing macroscale energetic formulations using advanced fabrication techniques both in bulk and thin film forms. Most importantly, these self-assembled NEMs have to exhibit excellent combustion performance at reduced sensitivity to external stimuli such as electrostatic discharge (ESD), friction and impact.

Increasing the efficiency of CIGS solar cells due to the reduced graphene oxide field layer of the back surface

Copper indium gallium selenide solar cells (CIGS-SCs) have gained attention due to their cost-effectiveness and environmentally friendly characteristics, making them a promising option for future electricity generation. The efficiency of CIGS-SCs can be enhanced by adding a back surface field layer (BSFL) under the absorber layer to reduce recombination losses. In this study, the electrical parameters, such as the series resistance, shunt resistance, and ideality factor, are calculated for CIGS-SCs with an advanced design, using the SC capacitance simulator (SCAPS) software. The detailed model used in the simulations considers the material properties and fabrication process of BSFL. By utilizing a reduced graphene oxide (rGO) BSFL, a conversion efficiency of 24% and a significant increase in the fill factor are predicted. This increase is primarily attributed to the ability of the rGO layer to mitigate the recombination of charge carriers and establish a quasi-ohmic contact at the metal-semiconductor interface. At higher temperatures, BSFL can become less effective due to an increased recombination and, in turn, a decreased carrier lifetime. Overall, this study provides valuable insights into the underlying physics of CIGS-SCs with BSFL and highlights the potential for improving their efficiency through advanced design and fabrication techniques.

ADVANCING MEMORY DENSITY: A NOVEL DESIGN FOR MULTIPLE-BIT-PER-CELL PHASE CHANGE MEMORY

Multiple-bit-per-cell phase-change memory (MPCM) has emerged as a promising solution to address the escalating demands for high-density, low-power, and fast-access memory in modern computing and data storage systems. This paper presents a novel device design aimed at enabling multiple bits per cell in phase-change memory, thereby significantly enhancing memory density while maintaining performance and reliability. Leveraging innovative material compositions and advanced fabrication techniques, the proposed design demonstrates the potential to push the boundaries of memory capacity, efficiency, and scalability. Through comprehensive simulation analysis and performance evaluations, we showcase the feasibility and advantages of the new device design, highlighting its potential to revolutionize memory architectures and meet the evolving needs of next-generation computing systems.

Investigation of hot deformation behavior and three-roll skew rolling process for hollow stepped shaft of Al–Zn–Mg–Cu alloy

The increasing demand for high-strength lightweight hollow shafts in transportation highlights the need for advanced fabrication techniques. Al–Zn–Mg–Cu alloys, noted for their superior properties, are selected for three-roll skew rolling (TRSR). In TRSR, the material undergoes combined axial tensile and radial compressive stresses. This study evaluates the feasibility of TRSR for producing high-strength lightweight hollow stepped shafts from Al–Zn–Mg–Cu alloy. An integrated approach, including constitutive modeling, hot processing map development, and TRSR numerical simulations/experiments, is employed to optimize the TRSR forming process. The constitutive model was established based on 300°C–450 °C & 0.01–10 s−1 hot compression and 350°C–430 °C & 0.1–5 s−1 high-temperature tensile test data. The established Johnson-Cook optimization by genetic algorithms (GA-JC) model and unified viscoplastic constitutive model, accurately capture the alloy's hot deformation behavior, exhibiting minimal average absolute relative errors (AARE) of 5.431% and 5.808%, respectively. Microstructure evolution analyses shed light on the predominant softening mechanisms, emphasizing dynamic recovery (DRV) at elevated strain rates and diminishing texture intensity with escalating deformation temperatures. The composite hot processing map delineates optimal process parameters (400°C–450 °C & 0.1s−1-1s−1), facilitating informed decision-making in manufacturing practices. The validation of numerical simulations through TRSR forming experiments with initial temperature of 450 °C for the billet and axial moving speed of 10 mm/s for the chuck in affirms the feasibility of producing hollow stepped shafts from high-strength Al–Zn–Mg–Cu alloy. Close agreement was found between simulated and experimental wall thickness variations. This study enhances understanding and optimization of TRSR forming for high-strength lightweight alloys, advancing industrial manufacturing methodologies.

Designer Metasurfaces via Nanocube Assembly at the Air-Water Interface.

The advent of metasurfaces has revolutionized the design of optical instruments, and recent advancements in fabrication techniques are further accelerating their practical applications. However, conventional top-down fabrication of intricate nanostructures proves to be expensive and time-consuming, posing challenges for large-scale production. Here, we propose a cost-effective bottom-up approach to create nanostructure arrays with arbitrarily complex meta-atoms displaying single nanoparticle lateral resolution over submillimeter areas, minimizing the need for advanced and high-cost nanofabrication equipment. By utilizing air/water interface assembly, we transfer nanoparticles onto templated polydimethylsiloxane (PDMS) irrespective of nanopattern density, shape, or size. We demonstrate the robust assembly of nanocubes into meta-atoms with diverse configurations generally unachievable by conventional methods, including U, L, cross, S, T, gammadion, split-ring resonators, and Pancharatnam-Berry metasurfaces with designer optical functionalities. We also show nanocube epitaxy at near ambient temperature to transform the meta-atoms into complex continuous nanostructures that can be swiftly transferred from PDMS to various substrates via contact printing. Our approach potentially offers a large-scale manufacturing alternative to top-down fabrication for metal nanostructuring, unlocking possibilities in the realm of nanophotonics.

Technological advances and challenges in constructing complex gut organoid systems.

Recent advancements in organoid technology have heralded a transformative era in biomedical research, characterized by the emergence of gut organoids that replicate the structural and functional complexity of the human intestines. These stem cell-derived structures provide a dynamic platform for investigating intestinal physiology, disease pathogenesis, and therapeutic interventions. This model outperforms traditional two-dimensional cell cultures in replicating cell interactions and tissue dynamics. Gut organoids represent a significant leap towards personalized medicine. They provide a predictive model for human drug responses, thereby minimizing reliance on animal models and paving the path for more ethical and relevant research approaches. However, the transition from basic organoid models to more sophisticated, biomimetic systems that encapsulate the gut's multifaceted environment-including its interactions with microbial communities, immune cells, and neural networks-presents significant scientific challenges. This review concentrates on recent technological strides in overcoming these barriers, emphasizing innovative engineering approaches for integrating diverse cell types to replicate the gut's immune and neural components. It also explores the application of advanced fabrication techniques, such as 3D bioprinting and microfluidics, to construct organoids that more accurately replicate human tissue architecture. They provide insights into the intricate workings of the human gut, fostering the development of targeted, effective treatments. These advancements hold promise in revolutionizing disease modeling and drug discovery. Future research directions aim at refining these models further, making them more accessible and scalable for wider applications in scientific inquiry and clinical practice, thus heralding a new era of personalized and predictive medicine.

Pulsed Electro-Codeposition of Graphene-Copper Hybrids with Enhanced Conductivity

The development of next generation materials and manufacturing technologies is critical for increasing industrial competitiveness, improving economic strength, and driving economy-wide decarbonization. Thermal and/or electrical conductivity-enhanced materials have been demonstrated as promising elements for the decarbonized industry sector with a wide variety of applications. High thermal conductivity materials enable new capabilities for the applications on sensors, detectors, and accelerators. The sluggish conduction cooling rate of conventional materials, such as copper, aluminum, or graphite, hinders the application of the cryogenic cooling systems. Graphene are two-dimensional nanocarbon materials with excellent physical and chemical properties, such as thermal and electronic conductivity, high mechanical strength, large specific surface area. The intrinsic physiochemical properties of graphene and a metal (copper) matrix, combined with advanced fabrication techniques, could tailor graphene-copper hybrid properties and make the hybrid as ideal thermal strap materials for conduction cooling systems.In this work, Faraday Technology Inc. and Utah State University will discuss an efficient, scalable, manufacturing-ready approach to produce high conductive graphene-copper hybrid foils/coatings and demonstrate their applications in thermal straps for conduction cooling, as well as in electronic devices as low resistance electrical pathways. The innovative electro-codeposition manufacturing process is based on the use of pulsed electric fields, for controlled, reproducible, scalable deposition of Cu and graphene materials simultaneously to form incorporated graphene-Cu hybrid foils. The graphene composition in the hybrid foils was confirmed by Raman spectrometry. The thermal conductivity of fabricated Cu-Graphene foil was ~50% higher than that of commercial Cu foil. Currently. we are scaling up the fabrication process for large scale production of graphene-copper hybrid foils for the thermal strap application.In summary, a scalable manufacturing process for synthesizing high conductive graphene-copper hybrids has been demonstrated. The work will be continued on thermal straps fabrication and performance evaluation, as well as other applications demonstration, such as low resistance backplanes for electronic devices. Acknowledgements: The financial support of DOE SBIR program through grant No. DE-SC0021676 (Phase I&II) is acknowledged.

Advancing large-scale thin-film PPLN nonlinear photonics with segmented tunable micro-heaters

Thin-film periodically poled lithium niobate (TF-PPLN) devices have recently gained prominence for efficient wavelength conversion processes in both classical and quantum applications. However, the patterning and poling of TF-PPLN devices today are mostly performed at chip scales, presenting a significant bottleneck for future large-scale nonlinear photonic systems that require the integration of multiple nonlinear components with consistent performance and low cost. Here, we take a pivotal step towards this goal by developing a wafer-scale TF-PPLN nonlinear photonic platform, leveraging ultraviolet stepper lithography and an automated poling process. To address the inhomogeneous broadening of the quasi-phase matching (QPM) spectrum induced by film thickness variations across the wafer, we propose and demonstrate segmented thermal optic tuning modules that can precisely adjust and align the QPM peak wavelengths in each section. Using the segmented micro-heaters, we show the successful realignment of inhomogeneously broadened multi-peak QPM spectra with up to 57% enhancement of conversion efficiency. We achieve a high normalized conversion efficiency of 3802% W−1 cm−2 in a 6 mm long PPLN waveguide, recovering 84% of the theoretically predicted efficiency in this device. The advanced fabrication techniques and segmented tuning architectures presented herein pave the way for wafer-scale integration of complex functional nonlinear photonic circuits with applications in quantum information processing, precision sensing and metrology, and low-noise-figure optical signal amplification.

MoS2 augmentation in CZTS solar cells: Detailed experimental and simulation analysis

This study investigates the optimization of CZTS-based thin-film solar cells through the incorporation of MoS2 as an interfacial layer. Using SCAPS-1D simulation software, we analyzed the effects of layer thicknesses, carrier concentrations, and defect densities on device performance. The optimized CZTS (100 nm)/ MoS2(1000 nm)/ CdS(100 nm)/ ZnO(50 nm) structure demonstrated a significant efficiency increase to 19.01 % compared to 17.03 % for the CZTS (1100 nm)/ CdS(100 nm)/ ZnO(50 nm) cell. Key improvements include enhanced charge generation, quantum efficiency, and balanced carrier transport.Materials were synthesized using microwave-assisted methods and characterized by XRD and UV–vis spectroscopy. XRD confirmed the desired crystal structures, while optical bandgaps of 1.5 eV (CZTS), 1.3 eV (MoS2), 2.4 eV (CdS), and 3.3 eV (ZnO) were determined. Practical solar cells were fabricated using spin-coating techniques, with thicknesses of CZTS (122 nm)/ MoS2 (1038 nm)/ CdS(130 nm)/ ZnO(94 nm). While showing improved performance with the MoS2 layer, efficiencies were lower than simulated values due to fabrication-related defects. The best experimental cell achieved 1.89 % efficiency, compared to 1.38 % without MoS2.This research demonstrates the potential of MoS2 as an effective interfacial layer in CZTS solar cells, providing insights into optimizing layer properties for enhanced performance. The study also highlights the challenges in translating simulated improvements to practical devices, emphasizing the need for advanced fabrication techniques to minimize defects and maximize efficiency.

Asymmetrical Elongation of Branched Alkyl Chains in Non‐Fullerene Acceptors for Large‐Area Organic Solar Modules

AbstractWith the drive toward the development of large‐area organic solar cells (OSCs), there is a critical need for advanced fabrication techniques that ensure both their efficiency and scalability. In particular, a shift from toxic halogenated solvents to safer non‐halogenated alternatives such as o‐xylene, which have lower environmental and health impacts, is required. However, transitioning to non‐halogenated solvents can lead to serious problems, including aggregation within the active layer, which compromises film morphology and the resulting efficiency of OSCs. To address this aggregation, in the present study, the 2‐ethylhexyl (EH) groups in L8‐BO(EH‐EH) are replaced with longer chains (2‐heptylundecyl [HU], 2‐decyltetradecyl [DT], and 2‐dodecylhexadecyl [DH] groups) to synthesize the non‐fullerene acceptors (NFAs) of L8‐BO(HU‐HU), L8‐BO(HU‐DT), and L8‐BO(HU‐DH). The NFAs with the longer alkyl chains are highly soluble in o‐xylene and produce highly uniform films, making them more suitable for use in large‐area OSCs. Using the NFAs, slot‐die‐coated organic solar modules with an active area of 200 cm2 are fabricated; the L8‐BO(HU‐DT)‐based module exhibits an impressive power conversion efficiency of 11.44%. This work thus underscores the asymmetrical elongation of alkyl chains in the NFAs to mitigate severe NFA phase separation and improve film printability in the practical production of organic solar modules.

Toward Practical Applications of Engineered Living Materials with Advanced Fabrication Techniques.

Engineered Living Materials (ELMs) are materials composed of or incorporating living cells as essential functional units. These materials can be created using bottom-up approaches, where engineered cells spontaneously form well-defined aggregates. Alternatively, top-down methods employ advanced materials science techniques to integrate cells with various kinds of materials, creating hybrids where cells and materials are intricately combined. ELMs blend synthetic biology with materials science, allowing for dynamic responses to environmental stimuli such as stress, pH, humidity, temperature, and light. These materials exhibit unique "living" properties, including self-healing, self-replication, and environmental adaptability, making them highly suitable for a wide range of applications in medicine, environmental conservation, and manufacturing. Their inherent biocompatibility and ability to undergo genetic modifications allow for customized functionalities and prolonged sustainability. This review highlights the transformative impact of ELMs over recent decades, particularly in healthcare and environmental protection. We discuss current preparation methods, including the use of endogenous and exogenous scaffolds, living assembly, 3D bioprinting, and electrospinning. Emphasis is placed on ongoing research and technological advancements necessary to enhance the safety, functionality, and practical applicability of ELMs in real-world contexts.

Advancement in biomedical implant materials-a mini review.

Metal alloys like stainless steel, titanium, and cobalt-chromium alloys are preferable for bio-implants due to their exceptional strength, tribological properties, and biocompatibility. However, long-term implantation of metal alloys can lead to inflammation, swelling, and itching because of ion leaching. To address this issue, polymers are increasingly being utilized in orthopedic applications, replacing metallic components such as bone fixation plates, screws, and scaffolds, as well as minimizing metal-on-metal contact in total hip and knee joint replacements. Ceramics, known for their hardness, thermal barrier, wear, and corrosion resistance, find extensive application in electrochemical, fuel, and biomedical industries. This review delves into a variety of biocompatible materials engineered to seamlessly integrate with the body, reducing adverse reactions like inflammation, toxicity, or immune responses. Additionally, this review examines the potential of various biomaterials including metals, polymers, and ceramics for implant applications. While metallic biomaterials remain indispensable, polymers and ceramics show promise as alternative options. However, surface-modified metallic materials offer a hybrid effect, combining the strengths of different constituents. The future of biomedical implant materials lies in advanced fabrication techniques and personalized designs, facilitating tailored solutions for complex medical needs.

Photoelectrode materials for photo-assisted electrochemical water treatment

Mohamed Ateia Ibrahim (environmental engineer and group leader at the US Environmental Protection Agency and adjunct assistant professor at Rice University) and Ashley Hesterberg Butzlaff (environmental engineer at the US Environmental Protection Agency) discuss material-based guidelines for optimizing photoelectrode design with a focus on utilizing advanced nanostructure fabrication techniques to enhance charge separation and transport, as well as identifying and integrating the most effective co-catalysts to improve efficiency and stability. These insights are critical for the development of practical and efficient photo-assisted electrochemical systems, essential for future water-treatment technologies.

Experimental Proof of Principle of 3D-Printed Microfluidic Benthic Microbial Fuel Cells (MBMFCs) with Inbuilt Biocompatible Carbon-Fiber Electrodes.

Microbial fuel cells (MFCs) represent a promising avenue for sustainable energy production by harnessing the metabolic activity of microorganisms. In this study, a novel design of MFC-a Microfluidic Benthic Microbial Fuel Cell (MBMFC)-was developed, fabricated, and tested to evaluate its electrical energy generation. The design focused on balancing microfluidic architecture and wiring procedures with microbial community dynamics to maximize power output and allow for upscaling and thus practical implementation. The testing phase involved experimentation to evaluate the performance of the MBMFC. Microbial feedstock was varied to assess its impact on power generation. The designed MBMFC represents a promising advancement in the field of bioenergy generation. By integrating innovative design principles with advanced fabrication techniques, this study demonstrates a systematic approach to optimizing MFC performance for sustainable and clean energy production.

Mechanical properties and biodegradability of crab shell-derived exoskeletons in orthopedic implant design

This review paper explores the innovative application of crab shell-derived exoskeleton materials, specifically chitin and chitosan, in the design of orthopedic implants. The urgent need for sustainable, biocompatible, and mechanically robust materials in medical applications guides this comprehensive analysis. We assess the mechanical properties of crab shell derivatives, highlighting their adequate strength and durability which are essential for successful orthopedic applications. This study also evaluates the biodegradability of these materials, an attribute that stands out for its potential to minimize long-term bodily impacts and reduce the need for secondary surgeries. Comparative analyses against traditional implant materials such as metals and ceramics are provided to underline the advantages and current limitations of crab shell-derived biopolymers. The review encompasses recent case studies and design innovations, including advanced fabrication techniques like 3D printing, which could integrate these biopolymers into future orthopedic solutions. Finally, we discuss the ongoing challenges and research gaps that must be addressed to harness the full potential of these biological materials in clinical settings. This paper aims to inform researchers and practitioners about the promising prospects of crab shell-derived materials, advocating for continued research and development in this promising area of orthopedic implant technology.

Shape Programming of Porous Bilayer Hydrogel Structures

Abstract Shape-programmable materials have garnered significant attention for their ability to morph into complex three-dimensional (3D) configurations under external stimuli, with critical applications in the fields of biomedical engineering, soft robotics, and sensing technologies. A current challenge lies in determining the geometric parameters of the initial two-dimensional (2D) structure and the intensity of the external stimulus required to achieve a target 3D shape. In this work, we introduce a novel inverse design strategy based on hole pattern engineering. Utilizing a temperature-sensitive bilayer hydrogel with differing coefficients of thermal expansion in each layer, we achieve controlled bending deformations by varying the porosity distribution in one of the layers. Drawing on the Timoshenko theory on bimetallic beam, we establish a quantitative relationship between porosity and curvature, allowing for the hole distribution of the initial structure to be tailored to the desired curvature. We demonstrate the efficacy of our inverse design approach with several prototypical 3D structures, including variable-curvature strip and ellipsoidal surface, validated through finite element simulations and experimental trials. This strategy paves the way for advanced fabrication techniques in developing smart materials and devices with programmable shapes.

Electrode Engineering Study Toward High‐Energy‐Density Sodium‐Ion Battery Fabrication

Sodium‐ion batteries (SIBs) are emerging as promising energy storage technologies, particularly for grid‐scale applications, due to their low material costs stemming from abundant natural resources. Meeting the increasing demand for higher energy density requires the development of innovative electrode and electrolyte materials, along with advanced analytical and fabrication techniques. However, the energy density of SIBs is often evaluated based solely on the capacities and cell voltages of active materials in half‐cell configurations, neglecting engineering considerations for full‐cell configurations. This study investigates the effects of electrode composition and the balance in capacities between positive and negative electrodes (N/P ratio) on the performance of full‐cell configurations, using Na3V2(PO4)3 (NVP) and hard carbon (HC) as representative electrode materials. Through a systematic analysis, an optimal composition for NVP and HC electrodes is proposed, considering areal capacity and capacity retention during full‐cell operations. Additionally, the importance of balancing the N/P ratio and the necessity of presodiation techniques to achieve high‐energy‐density SIBs are underscored. Overall, this work sheds light on key factors influencing the performance of SIBs and provides insights into strategies for enhancing their energy density and operational efficiency.