Charge Capacity Research Articles

Lithium tantalate film prepared by RF magnetron sputtering and effect of thickness on performance of inorganic electrochromic devices

Lithium tantalate (LiTaO3) thin films of varying thicknesses were deposited using RF magnetron sputtering for applications in electrochromic devices. The microstructural, optical and electrical properties of the films were systematically investigated. Microstructural analysis revealed that with increasing LiTaO3 films thickness, more island particles appeared and distributed densely and uniformly. Micro-cracks formed owing to the increased internal stress and the surface roughness increased significantly. LiTaO3 films exhibited high transmittance in the visible spectral range but showed significant absorption at wavelengths below 300 nm. The increasing LiTaO3 films thickness resulted in higher resistance and lower leakage current. Inorganic all solid electrochromic devices were fabricated using LiTaO3 film as the ion conductor layer. The charge capacity (ΔQ) decreased with increasing LiTaO3 film thickness, primarily due to Li+ transfer at the interface. Adjusting the deposition sequence of the of WO3 and NiO layer effectively mitigated the loose fiber-like structures and cavities in WO3. The presence of island-like particles and increased surface roughness introduced higher interfacial impedance and charge transfer resistance, further hindering Li+ transport. These factors resulted in irreversible Li+ insertion/extraction processes, ultimately degrading the electrochromic performance.

Multi-objective model for electric vehicle charging station location selection problem for a sustainable transportation infrastructure

The transportation industry mostly depends on conventional vehicles, leading to significant adverse effects on the environment. The widespread usage of electric vehicles can be seen as a relief for this problem. However, the success of electric vehicles largely depends on the availability and proper deployment of charging station infrastructure. It is crucial for cities to strategically select suitable locations for charging stations with adequate capacity levels to promote sustainable and environmentally-friendly transportation options. Hence, in this study, a multi-objective model is proposed for the electric vehicle charging station location selection and capacity allocation problem. The model aims to maximize customer satisfaction, minimize total risk, and minimize costs as key objective functions. To manage the demand effectively, the region of interest is divided into grids. The proposed multi-objective model is applied to the European side of Istanbul and solved by using AUGMECON2 technique. Finally, computational analyses are presented based on scenarios including different demand values. These analyses provide valuable insights into the effectiveness of the proposed model and its implications for achieving sustainable transportation in Istanbul.

Achievement of in-situ solid-to-solid conversion mechanism of thick ZnO-based anodes (30 mAh cm−2) in lean electrolyte environment for alkaline Ni[sbnd]Zn batteries

Alkaline NiZn batteries exhibit promising prospects owing to the advantages on safety, cost, eco-compatibility and considerable energy density. Nevertheless, their commercialization is still under great restrictions owing to the poor cycling life. To overcome this challenge, it is critical to explore the charge storage behavior and the corresponding failure mechanism of full cells in practical environment with thick electrodes and lean electrolyte. Herein, an in-situ ZnO↔Zn conversion dominate mechanism is accomplished in the system assembled with ZnO@C as anode with 100 % depth of charge (DOC) and a charge capacity of ~30 mAh cm−2, which can induce all the Zn formed in the core, resulting in dendrites and deformation-free charging. With a lower DOC of ~33 %, the cell can be well remained for ~320 cycles with a high average coulombic efficiency of ~93 % cycled at 10 mA cm−2/10 mAh cm−2. Even after the cell failure, there is still no dendrites or passivation on the anode. Yet, Zn phase dominates the anode, and obvious polarization increase can be detected accompanied by the decrease of pH. Therefore, water decomposition, and mismatch of reaction kinetics of anode and cathode are proposed to be the main reason of cell failure.

The Effect of Nickel Addition on α-Fe2O3 Synthesis Using NaOH and Application as Lithium-Ion Battery Anode Material

Research has been conducted in the pursuit of developing the performance of batteries. The increasing demand for electronic devices and electric vehicles has driven the development of high-performance lithium-ion batteries (LIBs). Among the various anode materials, α-Fe2O3 has attracted significant attention due to its high theoretical specific capacity of 1007 mAh/g. However, its low conductivity and poor rate capability limit its practical application. To address these issues, this study investigates the addition of nickel (Ni) into α-Fe2O3 through a co-precipitation method. The synthesized materials were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy with Energy-Dispersive X-ray spectroscopy (SEM-EDX). The electrochemical performance was evaluated using an LCR meter and charge-discharge cycling. The results showed the addition of Ni improved the conductivity of the α-Fe2O3 material. The optimal Ni content was found as much as 18×10-4 mol which exhibits the highest conductivity and specific capacity. The synthesized α-Fe1.965Ni0.035O3 material demonstrated a specific charging capacity of 1.8433 mAh/g and a specific discharging capacity of 1.8388 mAh/g. These findings suggest that Ni-doped α-Fe2O3 has the potential to be a promising anode material for high-performance lithium-ion batteries (LIBs).

Economic analysis of parking, vehicle charging and vehicle-to-grid services in the era of electric vehicles

With the advances in electrical technologies (especially the vehicle-to-grid or V2G technologies), electric vehicles (EVs) now can be used as power storage. The latent power storage capacity in EVs can provide additional flexibility to the power system, and thus helps enhance the overall efficiency, stability and reliability of the power grid. With the V2G facility in place, EV users can choose to share their vehicles to the power grid as temporary storage while the vehicle is being parked or charged (termed as ‘V2G parking or charging service’). This study investigates the pricing and capacity decisions of parking, charging and V2G operators, subject to the EV users’ choice equilibrium. An EV user who demands parking or charging can choose the (conventional) dedicated parking or charging slot (managed by the parking or charging operator) or the slot of V2G facility such that his/her vehicle can be used by the power grid as temporary storage while being parked or charged (managed by the V2G operator). We formulate and analyze the EV user choice equilibrium subject to parking, charging and V2G service provision, and then investigate parking, charging and V2G operators’ optimal service fare and capacity decisions in different market regimes, where the operators may compete or cooperate with each other (e.g., charging and V2G facilities might be operated jointly). The main findings are as follows. (i) Introducing the V2G-based parking/charging service might earn a positive profit for the V2G operator and also benefit customers who request for parking or charging, but the parking and charging operators will suffer a loss. (ii) The competition between operators tends to reduce the service fares, while cooperation tends to increase the fares and yield more profits for the operators. (iii) The optimal capacity of parking, charging, or V2G facilities should be set to balance the marginal capacity acquisition cost and the marginal facility searching time cost. (iv) When V2G operator cooperates with parking/charging operator, if the additional gains of parking/charging operator through cooperation are smaller than that of V2G operator, the optimal service fare of parking/charging should be smaller, and thus will benefit the parkers/chargers (after V2G service is introduced). (v) The collaboration between parking (or charging) and V2G operators might also benefit the charging (or parking) operator. Overall, this study enhances the understanding in relation to parking and charging operators’ reactions to emerging V2G-based parking and charging services, and provides insights regarding how the V2G service should be planned and optimized.

Facile synthesis of in situ carbon-coated CoS2 micro/nano-spheres as high-performance anode materials for sodium-ion batteries.

In situ carbon-coated CoS2 micro/nano-spheres were successfully prepared by sulfuric calcination using the solvothermal method with glycerol as the carbon source without introducing extraneous carbon. This method prevents carbon agglomeration and avoids the cumbersome steps of the current technology. The composite demonstrates excellent sodium storage capacity as an anode material for sodium-ion batteries. The initial charge and discharge capacities were 1027 and 1224 mA h g-1 at 50 mA g-1, respectively, with an initial coulombic efficiency of 83.9%. The capacity of CoS2@C at 350 °C was maintained at 937 mA h g-1 after 140 cycles at a current density of 2 A g-1. The outstanding electrochemical performance is mainly attributed to the nanostructure design and the presence of in situ carbon. As revealed by the kinetic analysis, the pseudo-capacitive behaviour also contributed to the excellent electrochemical performance.

An LWIR QWIP FPA with sub-5mK NETD and large dynamic range

QWIP based on the GaAs/AlGaAs material system are commonly used to achieve LWIR FPA. This detector is constrained by the integration charge capacity of conventional integral-readout-reset mode CMOS readout integrated circuits. As a result, the technical specification for the temperature resolution of the infrared detectors, known as NETD, typically ranges from 20 mK to 30 mK. In this paper, we present a 320 × 256 LWIR QWIP FPA, which is formed by bonding quantum well detectors and a pixel-level DROIC. Notably, the NETD achieved by this detector is superior to 5 mK, with the DR exceeding 100 dB, and it operates effectively within a temperature range of 40 K to 80 K, demonstrating excellent adaptability to varying environmental temperatures.

Optimizing Si─O Conjugation to Enhance Interfacial Kinetics for Low-Temperature Rechargeable Lithium-Ion Batteries.

With the growing demand for high-voltage and wide-temperature range applications of lithium-ion batteries (LIBs), the requirements for electrolytes have become increasingly stringent. While fluorination engineering has enhanced the performance of traditional solvent systems, it has also raised concerns regarding cost, environmental hazards, and low reduction stability. Through strategic molecular bond design, a novel class of low-temperature (LT) solvents-siloxanes-is identified, meeting the demands of LT and high-voltage applications in LIBs. The d-p conjugation of the Si─O bond enhances voltage resistance and weakens the Li+-solvent interactions. By modulating the number of Si─O conjugated bonds, the type of anion clusters in the solvation structure can be controlled, ultimately leading to the formation of a LiF and Si─O-rich interfacial layer and facilitating rapid Li+ conduction. Consequently, the graphite||NCM811 pouch cell (2.3 Ah, 4.45 V) with a siloxane-based electrolyte retains 75.1% of room temperature capacity (RTC) at -50°C. The rapid interface kinetics allow a superior reversible charging capacity retention of 67.6% at -40°C, with good cycle stability at -20°C. This study provides new insights into solvent design to fortify LIB performance in harsh conditions.

Revealing the Effect of Curvature Structure in Hard Carbon Anodes for Lithium/Sodium Ion Batteries.

Heteroatom doping is the most common means to enhance the Li+/Na+ ions storage of hard carbon (HC). The explanation of the storage mechanism of heteroatom-doped HC is to increase the active site or widen the layer spacing while ignoring the effect of local bending structure induced by it. Meanwhile, the storage mechanism by the localized bending structure also lacks in-depth study. Herein, a locally curved configuration and an amorphous structure are designed by introducing different heteroatoms, respectively, and the mechanism of the two types of structures on the Li+/Na+ ions storage is explored. The density functional theory (DFT) calculation shows that the adsorption energy of Li+/Na+ ions is optimal at the appropriate curvature of 27.72 m-1. Serving as anode for lithium/sodium ion batteries in ester electrolytes, the optimized HCs demonstrate satisfied specific capacity and high-rate capability, respectively. Furthermore, the charging capacity below 1.0V of HC with suitable curvature microstructure reaches 84.8% and 90.1% of the total charge capacity, confirming that the curvature defects can better control the delithiation/desodiation process, and provide a higher energy density. This study enlightens new insights into the storage mechanisms of Li+/Na+ ions and provides guidance for better design of heteroatom-doped carbon anodes with superior performance.

Advancing aluminum-ion batteries: unraveling the charge storage mechanisms of cobalt sulfide cathodes

Rechargeable aluminum-ion batteries (AIBs) stand out as a potential cornerstone for future battery technology, thanks to the widespread availability, affordability, and high charge capacity of aluminum. However, the efficacy of current AIBs on the market is significantly limited by the charge storage process within their graphite cathodes. To fully realize the capabilities of AIBs, the discovery of a new cathode material is essential. Transition metal sulfides present an attractive option for cathode materials, although there has been a variety of conflicting reports regarding the exact nature of their charge storage mechanisms. This paper investigates cobalt sulfide (CoSx) cathodes in AIBs, with a particular focus on deciphering the mechanisms of charge storage. Through synthesis, electrochemical testing, and post-cycling characterization, we illuminate the roles of AlCl4− intercalation, cobalt sulfide to Al2S3 conversion, and sulfur to Al2S3 conversion in charge storage. As cycling progresses, Al2S3 synthesis from segregated sulfur segments emerged as the predominant mechanism, showcasing its potential to fully leverage the high capacity of aluminum metal and propel AIBs towards higher energy densities. Despite these promising findings, the study also uncovered significant challenges, notably material loss, intra-cathode diffusion limitations, and irreversible reactions that precipitously diminish charge capacity over time. These issues highlight the critical need for enhanced electrode stability, improved electrolyte compatibility, and accelerated aluminum diffusion. The research paves the way for further exploration of transition metal sulfides as cathode materials in AIBs, highlighting the imperative for innovations that bolster mechanical and chemical stability while optimizing ion transport. This work not only contributes to the fundamental understanding of charge storage in AIBs but also charts a course for the development of more durable and efficient battery systems.

Advancing solar thermal utilization by optimization of phase change material thermal storage systems: A hybrid approach of artificial neural network (ANN)/Genetic algorithm (GA)

Solar energy is critical to the global shift towards sustainable and low-carbon energy solutions. Unlike fossil fuels, solar energy produces no emissions during operation, making it a key driver of environmentally friendly power generation. However, the intermittency of solar power remains a challenge, necessitating efficient energy storage systems to ensure a steady supply. Thermal energy storage systems utilizing phase change materials (PCMs) offer a solution by storing excess solar energy and releasing it when needed. This study focuses on enhancing the charging capacity of the PCM within a novel triplex tube heat exchanger (TTHE). The design incorporates bionic-shaped fins to compensate for thermal conductivity within the PCM. Three artificial neural network (ANN) models were employed to estimate the melting duration for the PCM to attain liquid fractions of 0.5, 0.8, and 1. The expansion angle (θ), initial length (D), and length of fin branches (Z) were systematically varied to investigate their influence on heat absorption. The ANN models exhibited high accuracy, with R2 values of 0.998 for the liquid fraction of 0.5, 0.998 for the liquid fraction of 0.8, and 0.996 for the liquid fraction of 1, demonstrating their precise predictive capability. The results revealed that θ significantly reduced melting time, while Z consistently shortened the duration and eventually became the dominant factor. However, an excessive increase in these geometric parameters led to a counterproductive rise in the total melting time. Through optimization using a genetic algorithm, three optimal designs (design 1 (D1), design 2 (D2), and design 3 (D3)) were proposed. Compared to the fin-less TTHE, these designs reduced the full melting time by 71.58 %, 73.41 %, and 73.54 %, respectively. Faster melting improves the system's ability to store and release thermal energy more quickly, enabling more efficient utilization of solar power within the limited period of sunlight availability (usually 4–6 h a day). These findings underscore the potential of ANN-based approaches in optimizing the efficiency of solar energy storage systems.

Application of multi-modal temporal neural network based on enhanced sparrow optimization in lithium battery life prediction

This paper introduces the DeNet-Mamba-DC-SCSSA network, an advanced solution for predicting the Remaining Useful Life (RUL) of lithium-ion batteries, crucial for the safety and efficiency management of electric vehicles. Combining the robust Denoising Enhancement Network (DeNet), the Improved Sparrow Optimization Algorithm (SCSSA), the adept Mamba time-series model, and the proficient Dilated Convolution (DC), this model excels in precise noise handling and sophisticated feature extraction. DeNet diligently refines input data, mitigating noise interference, while Mamba skillfully captures sequential intricacies. DC, on the other hand, adeptly extracts features over varying time scales, ensuring meticulous RUL predictions.The model’s efficacy was rigorously tested on NASA and CALCE datasets and was benchmarked against cutting-edge algorithms. Remarkably, it reduced average RE and RMSE by 48.59% and 21.45%, respectively, showcasing its superior performance and accuracy. Further evaluation on the CALCE dataset against the latest methods affirmed its leading predictive precision and stability.The model’s robustness and practical applicability were further validated using real vehicle data from a new energy vehicle platform. In a challenging test, it accurately predicted the charging capacities corresponding to the mileage of four vehicles with minimal errors: 0.52 Ah, 1.03 Ah, 0.84 Ah, and 0.71 Ah. These results significantly surpassed those of other recent methods, highlighting the model’s exceptional generalizability and potential for real-world applications in electric vehicle battery management.

Influence of Electrolyte Saturation on the Performance of Li-O2 Batteries.

Electrolyte saturation can strongly affect the Li-O2 battery performance. However, it is unclear to what extent saturation reduction will impact the battery capacity. In this study, we investigated the influence of electrolyte saturation and distribution within a porous positive electrode on the deep discharge-charge capacities and cycling stability. The study used both models and experiments to investigate the change of electrolyte distribution, double-layer capacitance, ohmic resistance, and O2 concentration in the positive electrode at different electrolyte saturations. Results revealed that electrodes with 60% electrolyte saturation achieved almost the same maximum discharge (6.38 vs 6.76 mAh/cm2) and charge (5.52 vs 5.65 mAh/cm2) capacities with fully saturated electrodes. The partially wet positive electrode (40% saturation) obtained more cycles than the electrode with 100% saturation before the discharge capacity dropped below the cutoff point. However, the electrode with 40% saturation had a low average charging efficiency of 88.76%, whereas the fully saturated electrode obtained 98.96% charging efficiency. Moreover, the fully wet positive electrode had the lowest overpotential during cycling (1.26-1.39 V). The measured electrochemically active surface areas showed that even 40% saturation could sufficiently wet the positive electrode surface and obtain a double-layer capacitance (18.12 mF) similar to that with 100% saturation (20.4 mF). Furthermore, a considerable increase in O2 concentration at wetted surface areas was observed for the electrolyte saturation of less than 60% due to the significantly higher O2 diffusivity in the gas phase.

Correlation Between Microscopic Current Fluctuations Observed at Ultra-Microelectrodes and Macroscopic Bulk Electrolysis Performance in Redox-Active Microemulsions

Microemulsions (μEs) have been proposed as redox flow battery (RFB) electrolytes that maximize ionic conductivity and charge capacity by synergizing two immiscible phases. However, charge transfer during electrolysis in μEs is poorly understood. Here, we show that ultramicroelectrode electrolysis of ferrocene-loaded μEs −20%, 60%, and 90% water - reveals stochastic current fluctuations. These are differentiated in the scanning electrochemical microscopy (SECM) geometry, where power spectral density analysis showed distinct changes in the frequency contributions. SECM in the substrate generation-tip collection mode showed that fluctuations arise under mass-transfer control. Significant differences in the diffusion coefficient of ferrocene species were deducted from SECM approach curves, suggesting phase transfer behavior. Using bulk electrolysis, we calculated the charge accessibility and cycling behavior in the μEs. A decrease in the stochastic behavior of the μEs seems to correlate to a higher accessibility and cycling performance, with the 90% water μE displaying the best reversibility and the 60% the lowest. Altogether, these results suggest that Marangoni-type convection driven by concentration gradients and/or μE restructuring during charge transfer play a role in the electrochemical performance of μEs. This presents opportunities for screening and diagnosing the performance of these emerging RFB electrolytes.

Bimetallic Sulfide Hollow Nanocubes Heterostructure Promotes Dual Coupling of Conversion and Alloying/Dealloying Reactions to Achieve Durable Potassium-Ion Battery Anode.

Conversion and alloying-type transitional metal sulfides have attracted significant interests as anodes for Potassium-ion batteries (PIBs) and Sodium-ion batteries (SIBs) due to their high theoretical capacities and low cost. However, the poor conductivity, structural pulverization, and high-volume expansions greatly limit the performance. Herein, Co1-xS/ZnS hollow nanocube-like heterostructure decorated on reduced graphene oxide (Co1-xS/ZnS@rGO) composite is fabricated through convenient hydrothermal and post-heat vulcanization techniques. This unique composite can provide a more stable conductive network and shorten the diffusion length of ions, which exhibits a remarkable initial charge capacity of 638.5mA h g-1 at 0.1 A g-1 for SIBs and 606mA h g-1 at 0.1 A g-1 for PIBs, respectively; It is worth noting that the composite presents remarkable long stable cycle performance in PIBs, which initially delivered 274mA h g-1 and sustained the charge capacity up to 245mA h g-1 at high current density of 1 A g-1 after 2000 cycles. A series of in situ/ex situ detections and first principle calculations further validate the high potassium ions adsorption ability of Co1-xS/ZnS anode materials with high diffusion kinetics. This work will accelerate the fundamental construction of bimetallic sulfide hollow nanocubes heterostructure electrodes for energy storage applications.

Utilization of manganese ore waste in development of mesoporous Mn3O4 and spinel LiMn2O4 octahedrons as a cathode for Li-ion battery

Nowadays, research on extracting gainful materials from waste precursors is highly fascinating and possesses excellent economic importance. This contribution validates the utilization of waste manganese sulphate (MnSO4) solution produced during the Mn mining processes for value-added battery materials. Specifically, the nano-sized spherical Mn3O4 particles were prepared using the MnSO4 solution by a controlled crystallization process in high purity, which was subsequently employed to develop efficacious cathode material i.e. LiMn2O4 (LMO) by a scalable solid-state method. The structural and morphological properties of as-prepared Mn3O4 and LiMn2O4 are studied by various characterization techniques like XRD, FTIR, Raman spectroscopy, FE-SEM, FE-TEM, XPS, and BET. The investigation reveals the formation of highly crystalline and phase-pure materials. The well-defined truncated octahedral LMO was successfully demonstrated as cathode electrode materials in the assembly li-ion battery coin cell. The as-prepared pristine, highly crystalline LiMn2O4 exhibited specific charge and discharge capacities of 122 mAhg-1 and 116 mAhg-1, respectively at 0.1C and prolonged stability with 71.4% capacity retention after 900 cycles at the current density of 1C within the potential window of 3.6 to 4.5V. The superior cycling performance of LMO suggests the significance of surface orientation in achieving enhanced electrochemical performance.

Performance Evaluation of Desalination Battery Systems based on Synthesis Method of Carbon Nanotube-Carbon Felt Composite Electrodes

To enhance chlorine ion removal and increase the current charging capacity of a desalination battery system, carbon nanotubes were applied to a carbonaceous electrode. Two types of composite electrodes were fabricated by attaching multiwalled carbon nanotubes (MWCNTs) to a carbon felt (CF) electrode via dip coating (D-CNT@CF) and electrophoresis (E-CNT@CF). These composite electrodes were then tested within a desalination battery system to evaluate their chlorine ion removal efficiency and current charging performance during the charging process. Microflocs of MWCNTs were observed on the surface of D-CNT@CF, whereas a uniform coating of MWCNTs was achieved on the surface of E-CNT@CF. Performance evaluations revealed that chlorine ion removal rates improved by 3.5% for D-CNT@CF and by 19.4% for E-CNT@CF compared to that of CF. Furthermore, the time required to reach maximum current charge was 40.0% for D-CNT@CF and E-CNT compared to CF. @CF decreased by 60.0%. These findings suggest that surface modification of carbonaceous electrodes through electrophoresis can result in a more stable coating and improve the performance of desalination battery systems.

STUDYING THE ELECTROCHEMICAL PROPERTIES OF POTASSIUM-DOPED SODIUM-MANGANESE OXIDE CATHODE MATERIALS FOR SODIUM-ION BATTERIES

The development of layered sodium manganese oxide cathode materials with high capacity and long life is one of the keys to boosting the performance of sodium-ion batteries (SIBs), but it remains a great challenge. In this work, a potassium doped P2-type sodium manganese oxide, Na0.8K0.1Mn0.9O2 (NKMO), is developed as a high-capacity and long-lasting cathode for high-performance SIBs. Sodium-potassium-manganese oxide Na0.8K0.1Mn0.9O2 was synthesized by a conventional solid-state reaction method. Crystal structure and morphology of the NKMO material were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The NKMO material was utilized to fabricate CR2032-type coin cells, and later evaluated for its electrochemical characteristics. The electrochemical characteristics of NKMO were evaluated through cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charging-discharging (GCD) at different current densities on a NEWARE battery testing system. The NKMO material had a superior initial charge and discharge capacity, approximately 130 mAh.g-1 and 125 mAh.g-1, respectively, within the voltage range of 1.5-4 V at a current density of 0.1 C. Remarkably, the capacity remained stable at 100 mAh.g-1 even after 100 cycles. These findings indicate that NKMO is a highly promising cathode material for sodium-ion batteries.

Synthesis of graphitic carbon from empty palm oil fruit bunches through single-step graphitization process using K2FeO4-KOH catalyst as lithium ion battery anode

This research aims to optimize the graphitization process of carbon derived from Empty Palm Oil Fruit Bunches (EPOFB), a renewable biomass source, using a single-step K₂FeO₄-KOH impregnation-activation method. The results demonstrate that increasing the mass of K₂FeO₄, up to the optimal level, enhances the degree of graphitization, as confirmed by XRD and Raman spectroscopy. Optimal performance is observed with a catalyst mass of 0.11 g K₂FeO₄ in the C_ K₂FeO₄(0.11)KOH_800 sample, which exhibits a d002 spacing of 0.3356 nm, an IG/ID ratio of 2.42, a high surface area of 787.767 m²/g, and clearly defined graphitic layers in TEM images. Electrochemical testing of C_ K₂FeO₄(0.11)_KOH_800 reveals promising results, including the lowest charge transfer resistance (Rct) of 87.18 Ω, a significant area under the curve in cyclic voltammetry, a charging capacity of 330.3 mAh g⁻¹ at 0.1 C, with an excellent rate capability of 183 mAh g⁻¹ at 1 C after 100 cycles, maintaining a retention rate of 68.2 %. The single-step K₂FeO₄-KOH impregnation-activation method effectively enhances the graphitization of EPOFB-derived carbon, offering potential applications in high-performance lithium battery anodes.

Design of Experiments to Tailor the Potential of BSA-Coated Peptide Nanocomplexes for Temozolomide/p53 Gene Co-Delivery.

Background: Gene therapy can be viewed as a promising/valuable therapeutic approach directed to cancer treatment, including glioblastoma. Concretely, the combination of gene therapy with chemotherapy could increase its therapeutic index due to a synergistic effect. In this context, bovine serum albumin (BSA)-coated temozolomide (TMZ)-peptide (WRAP5)/p53 gene-based plasmid DNA complexes were developed to promote payload co-delivery. Methods: Design of experiments (DoE) was employed to unravel the BSA-coated TMZ-WRAP5/p53 nanocomplexes with the highest potential by considering the nitrogen to phosphate groups ratio (N/P), and the BSA concentration as inputs and the size, polydispersity index, surface charge and p53-based plasmid complexation capacity (CC) as DoE outputs. Results: The obtained quadratic models were statistically significant (p-value < 0.05) with an adequate coefficient of determination, and the correspondent optimal points were successfully validated. The optimal complex formulation had N/P of 1.03, a BSA concentration of 0.08%, a size of approximately 182 nm, a zeta potential of +9.8 mV, and a pDNA CC of 96.5%. The optimal nanocomplexes are approximately spherical. A cytotoxicity assay showed that these BSA-coated TMZ-WRAP5/p53 complexes did not elicit toxicity in normal brain cells, and a hemolysis study demonstrated the hemocompatibility of the complexes. The complexes were stable in cell culture medium and fetal bovine serum and assured pDNA protection and release. Moreover, the optimal BSA-coated complexes were able of gene transcription and promoted a significant inhibition of glioblastoma cell viability. Conclusions: The reported findings instigate the development of future research to evaluate their potential utility to TMZ/p53 co-delivery. The DoE tool proved to be a powerful approach to explore and tailor the composition of BSA-coated TMZ-WRAP5/p53 complexes, which are expected to contribute to the progress toward a more efficient therapy against cancer and, more specifically, against glioblastoma.