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Hard carbon (HC) materials have poor rate performance and low initial Coulombic efficiency, which limits their practical use in sodium-ion batteries. An effective structural design with a suitable porous structure and an optimized graphitic degree is much required to address these issues. Herein, a novel S-doped commercial HC, consisting of hierarchically porous channels offering additional active sites and storage capacity to facilitate sodium ion transport from a simple thermal treatment, is reported. S-doped HC delivers a plateau-dominated reversible capacity of 429 mAh g⁻¹ at 0.3 mA g⁻¹ and 252 mAh g⁻¹ at 30 A g⁻¹ with 90 % capacity retention after 1000 cycles. as the SIB anode. Utilizing a commercial NFM cathode and a pre-sodiated S-doped HC anode, the full cell produced a high energy density of 237 Wh kg⁻¹ at an average operating potential of 3.25 V. The 3-stage sodium-ion storage mechanism of the S-doped material is revealed and confirmed through ex-situ XRD, Raman, XPS, EPR, and SEM. A tool to complement and differentiate the storage mechanisms through ex-situ Raman is reported to enable the design and development of plateau-dominated HCs in SIBs.

Optimizing the electrode/electrolyte interface structure is the key to realizing high-energy-density Li-metal batteries (LMBs) with nickel-rich LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) cathode. Herein, a versatile additive, norbornene dicarboxylic anhydride (NA), is dedicated to constructing robust interphase layers in NCM811ǁLi batteries. Theoretical calculations and experimental results show that NA induces the formation of thin and stable cathode-electrolyte interface (CEI) / solid-electrolyte interface (SEI) films at the electrodes’ surfaces. The NA-induced CEI film on the cathode effectively protects NCM811 and improves its structural stability during long-term cycling, thus avoiding the material rupture and the dissolution of transition metals. On the other hand, the SEI film on the anode also enhances the performances of interface between electrolyte and Li-metal anode. A LiǁLi symmetric cell with NA exhibits excellent cycling stability at a current density of 1.0 mA cm⁻² for cycling 400 h. Furthermore, the molecular dynamics simulations verify that NA additive influences the desolvation behavior of Li⁺ and increases transport kinetics of Li⁺ on the electrode/electrolyte interfaces. Therefore, the NCM 811ǁLi battery containing NA additive obtains a high capacity retention of 78.77 % after 200 cycles with a coulombic efficiency of 99.5 %.

This paper aims to comprehensively evaluate the shear strength of various junctions between diamond chips and double copper bonded ceramic substrates. The study involves several stages, beginning with the deposition of Ti/Ni/Ag metallization system on diamond chips using a chemical vapor deposition (CVD) process. These metallization systems are selected to determine their suitability as ohmic contacts on diamond. In parallel, Ni/Au and Ni/Ag layers are electroplated onto the thick copper metallization of the ceramic substrate. Following these depositions, junctions are created for both Cu/Cu and C/Cu assemblies using different techniques: reflow process for AuGe solder joints, reflow-diffusion process for Ag-In joints, and a thermomechanical process for Ag nanoparticle joints. To assess the effectiveness of these techniques, the shear strength of the junctions is measured using a micro-shear test, which is analogous to a classical micro-scratching test. Additionally, the mechanical behaviors of the layers adjacent to the assemblies are analyzed through nano-indentation tests. Finally, the fracture surfaces are examined using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectrometry to identify the microstructure and damage modes. The work described in the paper exhibits several innovative aspects. It introduces the novel combination of Ti/Ni/Ag metallization system on diamond chips, evaluated for its suitability as ohmic contacts, potentially leading to improved electrical and thermal performance in diamond substrate applications. The study employs diverse junction creation techniques, such as reflow for AuGe solder joints, reflow-diffusion for Ag-In joints, and a thermomechanical process for Ag nanoparticle joints, allowing for a thorough comparison and identification of the most effective method for different scenarios. We have also introduced an integrated testing methodology, which combines micro-shear tests and nano-indentation tests and provides a robust framework for assessing both the shear strength and mechanical properties of the junctions and adjacent layers, enhancing the reliability and depth of the evaluation. The specific focus on metallization system and junctions suitable for diamond, known for its exceptional thermal and electrical properties, positions this work as highly relevant for advanced electronic and thermal management applications.

The novel electrochemical sensor was employed for the investigation of the uricosuric drug sulfinpyrazone (SLF), which is administered orally to treat gout and prevent stone formations. SLF is toxic to the liver and increases the risk of Stevens-Johnson syndrome and toxic epidermal necrolysis, which are life-threatening conditions. It is crucial to avoid aspirin, salicylates, and similar salicylic acid derivatives when taking uricosuric drugs, as salicylates can inhibit tubular uric acid secretion, especially at lower doses. Thus, determining SLF is highly significant. In the pursuit of intensive care and interactions involving SLF, an r-GO@CPE (reduced graphene oxide modified carbon paste electrode) was employed for the study of SLF. Various characterization techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray diffraction spectrum (EDS), Fourier Transform Infrared Spectroscopy (FTIR) and electron impedance spectroscopy (EIS), were utilized to analyse the electrode modifier. The resulting r-GO@CPE has an enriched electroactive surface area, a high standard heterogeneous rate constant (k_et), and a small charge resistance (R_ct) as compared with the Carbon paste electrode, which authenticates its good catalytic activity. The analytical investigation of SLF was achieved through voltametric techniques such as cyclic & square wave voltammetry (CV & SWV). Optimal results were attained at a pH of 9.2, revealing an oxidation peak within the potential range of 0.2–1.2 V. SWV was employed for the quantitative estimation of SLF, yielding a limit of detection (LOD) and a limit of quantification (LOQ) of 1.10 × 10⁻⁸ M and 3.6 × 10⁻⁸ M respectively. This novel approach was also applied to determine SLF concentrations in both biological, water & pharmaceutical samples.

Utilizing waste resources to produce materials that lessen environmental pollution is one of the current directions for sustainable development. In this study, we discuss the potential efficacy of nanoparticles (MCM-41, Co-MCM-41, and ALV-TiO₂/Co-MCM-41) in eradicating noxious benzene, toluene, ethylbenzene, styrene (BTES) vapors. The nanoparticles MCM-41 and Co-MCM-41 were made using pure Nano-silica extracted from rice husk. Additionally, Aloe vera extract was used to create the nanoparticles ALV-TiO₂/Co-MCM-41. The sol-gel method was used to create MCM-41, and Co-MCM-41 nanoparticles, and the doping method to prepare ALV-TiO₂/Co-MCM-41 nanocomposites. The same conditions were used for all experiments and the analysis of nanoparticle structure. According to the BET results, the nanoparticles' average pore size is between 5.6 and 14.9 nm, and their specific surface areas range from 207.4 to 793.8 m²/ g. In the physical adsorption mode, the properties of prepared nanoparticles were investigated, and the results showed that all three nanoparticles have significant removal capacity for BTES gas. They showed the highest theoretical successful adsorption capacity (MCM-41: 95.85 %, Co-MCM-41: 97.35 %, and ALV-TiO₂/Co-MCM-41: 100 %) in the first run. These materials' high capacity for toxic BTES vapor adsorption by the nanoparticles and highly reusable nature (up to 14 consecutive cycles) demonstrate their efficacy in the removal of toxic gases in relevant industries.

In this work, Mn₅₅Bi_45-xB_x (0 ≤ x ≤ 2) alloys were prepared by arc-melting, and the low-temperature ferromagnetic MnBi phase was investigated in 300 K. Through the XRD refinement results, it can be found that the lattice parameters of the alloys change with the B doping amount. When x = 1, an optimal room temperature spontaneous exchange bias effect was observed in the Mn₅₅Bi₄₄B. This phenomenon can be attributed to B with a smaller atomic radius occupying the Bi position, resulting in more Mn atoms into interstitial sites and more antiferromagnetic clusters on the ferromagnetic matrix. This work focuses on the effect of B doping on the structure and exchange bias behavior in Mn₅₅Bi₄₅ alloy, providing a way to design room temperature spintronic devices.

This study investigated weight loss and electrochemical impedance spectroscopy (EIS) to explore the inhibition potential of Anthonotha macrophylla leaf extract (AME) on mild steel corrosion in 0.5 M H₂SO₄ medium. The result shows that the highest inhibition efficiency of 90.47 % at 303 K and 80.02 % at 333 K were obtained. At temperatures of 303 K and 333 K, it was discovered that the corrosion rate decreased as the concentration of the AME inhibitor rose from 0.1 g/L $(7.73\times {10}^{-4}$gcm⁻²hr⁻¹) to 0.5 g/L $(2.27\times {10}^{-4}$ gcm⁻²hr⁻¹). The result of the EIS measurement is in consistent with that of the weight loss method. Adsorption isotherms portrayed that Tempkin and Freundlich's adsorption isotherms were obeyed. Calculated values of Ea, $∆H_{\mathrm{ads}}$ and $∆G_{\mathrm{ads}}$ suggested a physical adsorption mechanism. FTIR, SEM-EDX, and XRD measurements revealed that the AME inhibitor efficiently shields the mild steel surface from further corrosion attack by inducing the formation of passivated film on the mild steel surface. The calculated quantum parameters correlated with experimental results, thus, AME can be used as an alternative inhibitor for the protection of mild steel against corrosion.

In this paper we offer a new perspective on how the principles of high entropy design for oxide materials can be applied to lithium rich transition metal oxide cathodes. We discuss the structure, unique properties, and synthetic dependence of lithium rich transition metal oxide cathodes as well as some background on high entropy oxides. We then discuss the benefits of entropic stabilization in reducing the rigor and increasing the consistency of synthesizing phase pure cathodes materials. We draw parallels between the established temperature, time and transformation relationships used in synthesis of materials and electrochemistry to propose a voltage, time, and transformation analogue that can be used to help explore the phase transformations of lithium rich transition metal oxide cathodes over cycling. This proposed voltage, time, and transformation system is then used to explore the use of entropic stabilization of lithium rich transition metal oxide cathodes during electrochemical cycling. Finally, considerations for the design and limitations of entropic stabilization for lithium rich transition metal oxide cathodes are discussed, and solutions are offered.

The challenges posed by environmental pollution, global warming resulting from carbon dioxide emissions, and energy scarcity jeopardize the sustainable progress of humanity. Prioritizing the advancement and sustainability of renewable energy sources is imperative to bolster global efforts promoting the displacement of fossil fuels and attaining carbon neutrality. Diverse material categories have been explored, encompassing potential applications in nitrogen reduction reactions, carbon dioxide reduction, water electrolysis, biomass conversion, and battery catalysis. These materials have undergone refinement through techniques like alloy synthesis, introduction of defects/dopants, and construction of heterostructures, resulting in significant enhancements. While many catalysts have demonstrated excellent catalytic performance in reactions such as nitrogen reduction, carbon dioxide reduction, water splitting, and biomass conversion, numerous questions regarding catalyst structure, active site functionality, and catalytic mechanisms remain unanswered. In this review, we summarize the progress of nanomaterials in energy catalytic conversion (The process where catalytic nanomaterials facilitate the conversion of energy carriers or small molecules into valuable products) of small molecules over the past five years, and systematically illustrate the characterization of nanomaterials in chemical reactions by X-ray absorption spectroscopy (XAS). Utilizing XAS technology to identify the active components of catalysts, track the dynamic structural evolution of catalysts, and observe stable reaction intermediates in transition metal single-atom catalysts, transition metal oxides, and metal polycrystals. XAS shows promising potential in various fields such as carbon reduction, nitrogen reduction, biomass conversion and porous materials, garnering widespread recognition in the catalysis community.

In this work, the mechanical properties of Mo₃NiB₃ and Mo₂NiB₂ phases in Mo-Ni-B cermets were studied. The first-principles calculation results demonstrate the thermodynamic and mechanical stability of both Mo₃NiB₃ and Mo₂NiB₂. Among them, Mo₂NiB₂ shows superior stability and toughness compared to Mo₃NiB₃. On the other hand, the Young’s modulus and hardness values of Mo₃NiB₃ are higher than those of Mo₂NiB₂. Mo₃NiB₃ exhibits enhanced isotropy and stronger covalent bonding properties, as confirmed by DOS and Mulliken analysis. Further research shows that Mo₃NiB₃ has brittleness (B/G = 1.586) and high Vickers hardness (22.3 GPa), indicating its potential use as a wear-resistant material. To validate the accuracy of the theoretical calculations, Mo₃NiB₃ and Mo₂NiB₂ cermets were fabricated through vacuum hot pressing sintering, followed by comprehensive analysis of their microstructure and mechanical properties. Specifically, the experimentally measured compressive strength and hardness values of Mo₃NiB₃ (3213.2 MPa and 3264.2 HV0.3, respectively) were closely matched by the theoretical predictions. Notably, these experimental findings are in good agreement with the theoretically calculated values. This investigation provides reference value for a more in-depth analysis of the mechanical properties of Mo-Ni-B cermets, provides a theoretical and practical basis for its application in the field of materials, and promotes the development of Mo-Ni-B cermets materials.