Solid-state sodium batteries gain recognition as promising candidates for energy storage applications, offering enhanced safety and performance. However, their overall efficiency is limited by poor interfacial contact between the cathode active material (CAM) and the solid electrolyte (SE), as well as by interfacial instability. This underscores the imperative of establishing a chemically and electrochemically stable CAM/SE interface to ensure efficient charge transfer and long-term electrochemical performance. Herein, we report the optimization of the co-sintering process between Na3Zr2Si2PO12 NZSP, (SE), and Na0.67Fe0.5Mn0.5O2 NFMO, (CAM). A co-sintering temperature of 900 degrees C, which is suboptimal, yields a sodium-conducting interface that promotes intimate interfacial contact while preserving the bulk properties of both components, thereby enhancing interfacial compatibility. Thermal expansion mismatch between NFMO and NZSP is found to be minimal (<5 x 10(-6) K-1), reducing the risk of crack formation during cooling. The full-cell assembled using Na3Zr2Si2PO12 and Na0.67Fe0.5Mn0.5O2 composite cathode exhibits superior electrochemical performance with an initial discharge capacity of 149 mA h g(-1) at 0.1 C with the capacity retention of 70 % after 200 cycles. This excellent cycling stability is attributed to the well-engineered CAM/SE interface, which ensures efficient charge-transfer kinetics. This study provides guidance on the optimization of the co-sintering mechanism in the realm of achieving intimate electrode/electrolyte contact and can be a cornerstone for future research.

Lithium-sulfur batteries suffer from polysulfide shuttle (PS) and lithium metal anode instability. We developed a mixed-anion ionic liquid (IL) electrolyte combining N-trimethyl-N-propylammonium bis(fluorosulfonyl)imide (N1113FSI) with LiFSI and LiTFSI, enabling stable lithium metal passivation while suppressing polysulfide dissolution to sub-mM levels. Electrochemical testing demonstrates a specific capacity of 900 mA h g- 1 with 70% retention after 300 cycles. Electrochemical impedance spectroscopy (EIS) reveals a substantial reduction in charge-transfer resistance post-lithiation and stable impedance during extended cycling. Raman spectroscopy confirms effective polysulfide suppression. Notably, cell performance is insensitive to the electrolyte-to-sulfur ratio (10-45 µL mg- 1), in contrast to conventional ether-based electrolytes. Depth-resolved x-ray photoelectron spectroscopy (XPS) reveals that N1113FSI forms abundant LiF through efficient anion reduction, yielding a dense, inorganic-rich solid-electrolyte interphase (SEI). In contrast, P111i4FSI retains incompletely reduced anions and exhibits diminished LiF, demonstrating cation-dependent control of SEI chemistry. The N1113FSI interphase contains higher levels of LiF, Li-sulfide, oxidized sulfur, and inorganic oxygen species, which correlate with superior cycling stability. Compared to P111i4FSI, N1113FSI achieves higher discharge capacity (DC), faster Coulombic efficiency (CE) stabilization, and sustained reversibility. Tailored IL design effectively suppresses polysulfide solubility and engineers efficient SEI chemistry, mitigating shuttle effects and enabling stable Li-S operation across varying electrolyte concentrations.

Solid polymer electrolytes (SPEs) based on poly(ethylene oxide) (PEO) provide an inherently safer and more sustainable alternative to liquid electrolytes for sodium metal batteries; however, their practical deployment is limited by low ionic conductivity, inefficient Na+ transport, and unstable electrode-electrolyte interfaces under complete solid-state conditions. Here, we report a detailed investigation of a weakly coordinating, borate-based sodium salt, sodium difluoro(oxalato)borate (NaDFOB), incorporated into PEO-based SPEs. A dual-salt strategy combining NaDFOB with sodium bis(fluorosulfonyl)imide (NaFSI) is employed to harness complementary mixed-anion functionalities while reducing overall fluorine content. Differential scanning calorimetry (DSC) shows a pronounced reduction in PEO crystallinity for the mixed-anion PEO/NaFSI/NaDFOB electrolyte (EO : Na = 20 : 1) (chi(c) approximate to 39-41%), indicating enhanced amorphous character favourable for ion transport. Additionally Fourier transform infra-red spectroscopy (FTIR) measurements reveal shifts in the C-O-C stretching region and changes in [FSI](-)/[DFOB](-) vibrational modes, confirming altered polymer-salt interactions, while solid-state Na-23 and F-19 NMR further validate these findings by showing broadened resonances and distinct Na+ coordination motifs consistent with weakened ion-pairing and increased Na+ mobility. The optimised PEO/NaFSI/NaDFOB electrolyte exhibits a high ionic conductivity of similar to 1.3 & times; 10(-3) S cm(-1) at 80 degrees C in comparison to the single-salt electrolytes, alongside suppressed polymer crystallinity and modified Na+ coordination environments. Na-0 & Vert;Na-0 symmetric cells fabricated with the optimised mixed-anion electrolyte (EO : Na = 20 : 1) exhibit stable cycling for over 800 hours at 50 degrees C, below the melting point of PEO. Although IL-containing plasticised formulations were included for comparison, the IL-free mixed-anion electrolyte (PEO/NaFSI/NaDFOB) remarkably delivered lower overpotentials and markedly improved interfacial stability and cycling performance, demonstrating fully solid-state operation. With an anodic stability >5.8 V (vs. Na+/Na), suppressed PEO oxidation, and effective passivation, behaviour this work establishes borate-imide dual-salt polymer electrolytes as a promising, reduced-fluorination alternative to conventional [PF6](-) and to the highly fluorinated, environmentally persistent PFAS-like [TFSI](-)-based systems, for safe, stable, and high-performance all-solid-state sodium metal batteries.

The development of non-flammable, non-volatile electrolytes is important for safer lithium and sodium batteries, to facilitate our transition to a net zero economy, but the reliance on fluorine-containing anions brings significant environmental concerns. Here, acesulfamate based ionic liquids (ILs), sodium acesulfamate (Na[ace]) and lithium acesulfamate (Li[ace]) are introduced as promising new fluorine free materials as a more sustainable alternative to the perfluorinated anions (BF _4 , PF _6 , FSI and TFSI) currently utilised in energy storage devices. The resulting ammonium, phosphonium and pyrrolidinium acesulfame ILs showed promising physicochemical properties with a relative high conductivity (e.g. 1.4 × 10 ^−4 S cm ^−1 at 30 °C for [N _1222 ][ace]) and a wide electrochemical stability window (∼4 V). Lithium and sodium acesulfamate salts were synthesised from potassium acesulfamate (ACE-K) via an acid-base reaction. The use of acesulfamate ILs as electrolytes was investigated by mixing with sodium or lithium acesulfamate salts and characterisation of their physicochemical and electrochemical properties. Polyethylene oxide based free standing membranes composed of [N _2222 ][ace] with Na or Li [ace] were fabricated and tested in symmetrical Li or Na metal cells, demonstrating good electrochemical performance in both variable current density tests and longer-term cycling at elevated temperatures. Thus, the new Li and acesulfamate salts, the ILs and their mixtures, represent valuable new materials for the development of fluorine free electrolytes for energy storage devices.

The dynamics of an impacting droplet can be controlled by microstructuring the surface. This work presents a numerical investigation of droplet impact characteristics on a hydrophobic surface microstructured with sinusoidal wavy patterns. The effects of amplitude and wavelength of the wavy surfaces on droplet deformation are analyzed for different impact velocities. A dynamic contact angle model is incorporated into the numerical method to track the three-phase contact line accurately. The influence of the Weber number on the wettability transition is analyzed, and the flow characteristics inside the droplet at different flow regimes are explained. A regime map is prepared to show the transition between different regimes for different surface attributes and Weber numbers. The initial contact of the impacting droplet with the surface is influenced by the amplitude and wavelength of the roughness element, leading to different wettability states. The Wenzel (wetting), Cassie (non-wetting), and mixed wetting states affect the droplet's spreading, recoiling, and rebound characteristics. The Cassie state of a plane surface is transformed into the Wenzel state due to microstructuring the surface with small amplitude and wavelength. A further increase in amplitude and wavelength leads to a transition from the Wenzel state to a mixed state, and finally from the mixed state to the Cassie state. The amplitude-controlled mixed state results in partial rebound of the droplet, whereas the wavelength-controlled state results in partial rebound and rebound with droplet breakup. The study may aid in designing droplet retention surfaces required for practical applications.

Surface wettability significantly affects the dynamic behavior of impacting droplets. Recent studies have utilized the electrowetting (EW) effect to control the spreading and recoiling motions of droplets impacting hydrophobic substrates by modulating surface wettability. Electrowetting enhances droplet spreading while substantially reducing rebound tendencies. This study uses numerical methods to analyze the droplet’s behavior on a hydrophobic substrate under partial electrowetting conditions. When a droplet reaches its maximal spreading width, the electrowetting process is turned off. This method increases the maximal spreading width while decreasing the recoiling time compared to scenarios without electrowetting. Therefore, droplet rebounds from the surfaces quickly. Furthermore, the recoiling time decreases with higher frequencies and Weber numbers. Understanding the droplet dynamics has broad applications in areas such as self-cleaning surfaces, spray cooling, and microfluidic devices.

The droplet’s impact dynamics on the superhydrophobic substrate can be manipulated by varying the viscosity of the droplet. A phase-field numerical technique with a dynamic contact angle (DCA) approach is used to investigate the droplet impact on a superhydrophobic surface. With the increase in the Weber number (We), the spreading factor ( β) of the impacting droplet increases, and the non-dimensionalized spreading height decreases for all Ohnesorge numbers. The minimum value of non-dimensionalized spreading height is attained in the recoiling phase rather than when the droplets attain maximum spreading (D_max ) . It means the droplet velocity decreases at the center when the droplet is at its maximum spreading factor. The spreading factor ( β) decreases, and the minimum value of non-dimensionalized spreading height increases at the droplet's center with the increase in the Oh for all We because of the more losses of kinetic energy (K.E) into the viscous dissipation energy. The time required to rebound the droplet is the same up to Ohnesorge number = 0.0916, and after an increment in Ohnesorge number, bouncing time increases. With the further increase in Ohnesorge number, the droplet completely suppresses the rebound behavior of the droplets. The droplet's height decreases as the Ohnesorge number increases for all Weber numbers when the droplet starts to rebound. The percentage change in β_max is 61.75

Lithium-sulfur (Li-S) batteries are among the most promising next-generation energy storage technologies due to their high theoretical energy density and the abundance of sulfur. However, their practical implementation is limited by active material loss, unstable electrode interfaces, intermediate polysulfide dissolution, and low sulfur utilization. In this study, we present a hybrid binder composed of a lithium-ion-conductive poly(ionic liquid) (PIL), poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (PDADMA-TFSI), and carboxymethyl cellulose (CMC) engineered to operate synergistically with ionic liquid (IL) electrolytes based on trimethylisobutylphosphonium bis(fluorosulfonyl)imide [P111i4][FSI] and N-trimethyl-N-propylammonium bis(fluorosulfonyl)imide [N1113][FSI]. This PIL-CMC binder significantly improves interfacial stability and enables efficient sulfur utilization in polysulfide-free cycling. Among all combinations tested, 50 mol% LiTFSI in [N1113][FSI] exhibited the best electrochemical performance, sustaining capacities above 1100 mA h g-1 for over 100 cycles at 50 degrees C. A reduced total binder content formulation (5 wt% PIL and 5 wt% CMC) maintained comparable performance, suggesting potential for further optimization. Electrochemical analysis revealed low voltage polarization and high Coulombic efficiency of up to 99.5 %, while UV-vis and Raman spectroscopy confirmed the absence of dissolved polysulfides. Overall, this work demonstrates a robust and scalable strategy for realizing additive-free, thermally stable Li-S cathodes, emphasizing the importance of binder-electrolyte integration in the design of high-performance Li-S batteries.

The formation of unstable interphases on the anode and cathode severely limits the long-term cycling performance of sodium-ion full cells. This study demonstrates that the use of low-viscosity, weakly solvating linear carbonates-dimethyl carbonate (DMC) and diethyl carbonate (DEC) - promotes the involvement of the main salt anion (PF6 -) and additive anions (BF4 - and TFSI-) in the primary solvation shell. This leads to the formation of an anion-rich, ion-conducting interphase on the hard carbon (HC) anode surface, significantly enhancing its initial coulombic efficiency (ICE) and rate performance. Additionally, it promotes the formation of an inorganic-rich cathode electrolyte interphase (CEI) on the titanium doped sodium nickel manganese oxide (NMTNO) cathode. The full-cell utilizing the modified electrolyte demonstrates an excellent cycling stability, with a stable areal capacity of 1.25 mAh cm-2 at a current rate of 0.25 mA cm-2 after 200 cycles. Moreover, the sodium-ion full-cell exhibited impressive high-rate performance, maintaining a stable capacity of 0.75 mAh cm-2 at a current rate of 1.5 mA cm-2, with a capacity retention of over 90% after 300 cycles.

The electrode/electrolyte interfacial contact, ionic percolation pathways, and charge transfer resistance within the cathode significantly impact the performance and lifespan of all-solid-state sodium batteries (AS3Bs). Addressing these issues requires optimization of the composite cathode architecture and the electrode/electrolyte interface in AS3Bs. One major challenge in developing composite cathodes with oxide solid electrolytes is selecting the appropriate thermal processing temperature to ensure intimate contact between the cathode active material and solid electrolyte while ensuring a sufficient ionic percolation pathway inside the composite cathode. In this study, we present an approach for fabricating a composite cathode by cofiring sodium vanadium fluorophosphate (Na3V2(PO4)2F3, NVPF) and the sodium superionic conductor (Na3Zr2Si2PO12, NZSP) at 700 °C using an optimized weight ratio. This method ensures reduced interfacial resistance between NVPF and NZSP while establishing an efficient ionic percolation pathway. To further enhance ionic percolation within the composite cathode, residual voids are filled with a polymer electrolyte composed of PEO/NaClO4. Benefits of the dense composite cathode structure, a stable NVPF/NZSP interface, negligible pores in the composite cathode, and a three-dimensional electronic and ionic percolation network facilitate the greater utilization of cathode active material with almost no capacity degradation upon long-term cycling. The full cell, with the optimized composite cathode, delivers an initial discharge capacity of 114 mA h g-1 at 0.1 C, retaining 85% of its capacity after 500 cycles with a 99% Coulombic efficiency and excellent rate capability at 1 C.

Despite the potential for a greater energy density than lithium-ion batteries, polysulphide dissolution, the polysulphide shuttle effect, and lithium metal instability impede the commercialization of lithium–sulfur (Li–S) batteries.

Despite the advancements in additive manufacturing to prepare personalized implants of complex geometries, the additive manufacturing of Mg alloys has posed significant challenges. In this work, commercially pure (Cp) Mg and Mg-2Ag-2Sn alloys were additively manufactured via laser-powder bed fusion (L-PBF). Elemental powders were ball-milled to prepare the alloy powder for L-PBF. Optimized fabrication parameters were determined by preparing tracks at varying laser parameters. Non-spherical powders could be successfully utilized in this process. Microstructural analysis by optical microscopy, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy revealed the presence of different phases, including some Al uptakes from the substrate. Hardness studies revealed a 63% increase in the hardness of the Mg-2Ag-2Sn alloy compared to Cp Mg. Additionally, the fabricated Mg-2Ag-2Sn alloy system demonstrated almost two-and-a-half-fold improved corrosion resistance than Cp-Mg, making it potentially viable for orthopaedic implants. This study demonstrates the fabrication of Cp Mg via additive manufacturing by laser powder bed fusion (LPBF), accompanied by systematic optimization of the processing parameters. Furthermore, a comparative analysis between pure Mg and the Mg-2Ag-2Sn alloy is conducted to evaluate their properties. The results demonstrate that LPBF is a promising process for the advanced manufacturing of Mg-based alloys for biomedical applications.

Nitinol parts prepared by wire arc additive manufacturing were heat-treated to impart excellent superelastic recovery, while exhibiting good corrosion resistance and cytocompatibility, for biomedical applications.

Block copolymers (BCPs) as solid electrolytes for batteries are usually designed to have an ion-solvating block for ion conduction and an ionophobic block for providing mechanical strength. Here, we show a novel solid polymer electrolyte (SPE) for sodium batteries based on a poly(vinyl benzoate)-b-poly(diallyldimethyl ammonium bis(trifluoromethanesulfonyl)imide) PVBx-b-PDADMATFSIy-b-PVBx ABA triblock copolymer. The SPE triblock copolymer comprises a polymerized ionic liquid (PIL) ion-solvating block combined with NaFSI salt as an internal block and an ionophilic PVB as an external block. Four distinct compositions with varying chain lengths of the blocks were synthesized by reversible addition−fragmentation chain-transfer (RAFT) polymerization. The neat copolymers were subsequently mixed with NaFSI in a 2:1 mol ratio of Na to ionic monomer units. Through comprehensive analysis using differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR), it was revealed that the ion coordination within the polymer–salt mixtures undergoes changes based on the composition of the starting neat polymer. Electrochemical evaluations identified the optimal composition for practical application as PVB11.5K-b-PDADMATFSI33K-b-PVB11.5K, showing an ionic conductivity at 70 °C of 4.2 × 10−5 S cm−1. This polymer electrolyte formulation was investigated for sodium in Na|Na symmetrical cells, showing an overpotential of 200 mV at 70 °C at 0.1 mA cm−2. When applied in a sodium–air battery, the polymer electrolyte membrane achieved a discharge capacity of 1.59 mAh cm−2 at 50 °C.

Sodium batteries are considered a promising candidate for large-scale grid storage at tropical climate zone, and solid-state sodium metal batteries have a strong proposition as high energy density battery. The main challenge is to develop ultra-pure solid-state ceramic electrolyte and compatible metal interface. Here, a scalable and energy-efficient synthesis strategy of sodium (Na) Super Ionic CONductor, Na1+xZr2SixP3-xO12 (x = 2, NZSP) solid electrolyte, has been introduced with the complete removal of unreacted zirconium oxide (ZrO2) impurities. Additionally, the reaction mechanism for the formation of pure phase NZSP is reported for the first time. The NZSP prepared by utilizing the Zr precursor, i.e., tetragonal zirconium oxide (t-ZrO2) derived from the Zr(OH)(4) gets quickly and completely consumed in the synthesis process leaving no unreacted monoclinic ZrO2 impurities. The synthesis process only needs a minimum stay of 4h, which is three times less than the conventional synthesis method. The elimination of ZrO2 impurities results in a 2.5-fold reduction in grain boundary resistivity, showcasing a total ionic conductivity of 1.75 mS cm(-1) at room temperature and a relative density of 98%. The prepared electrolyte demonstrates remarkable resistance to dendrite formation, as evidenced by a high critical current density value of 1.4 mA cm(-2).

An anionic-additive electrolyte system is introduced by incorporating Lithium tetrafluoroborate (LiBF4) into a conventional base electrolyte for high-voltage LiNi0.Mn-5(1).O-5(4) (LNMO) cathodes in lithium-metal batteries. At high voltages, the sacrificial oxidation of LiBF4 mitigates electrolyte degradation and forms a robust cathode electrolyte interface (CEI) enriched with boron and fluorine-based components, which protects against active material corrosion. Density Functional Theory (DFT) studies reveal that BF4- is more readily oxidized, while MD simulations validate the CEI's inorganic composition. Initial cycling with a specialized charge-discharge protocol ensures optimal use of the additive, resulting in a uniform, thin (4-6 nm) CEI on the LNMO cathode. The CEI formed in anionic-additive electrolyte system effectively suppresses transition metal dissolution and surface degradation, enhancing long-term cycling performance. The LiBF4-enhanced electrolyte also lowers overpotential and promotes more uniform Li deposition compared to the base electrolyte. At a 1 C-rate, the LNMO cathode with a Li metal anode and optimized electrolyte achieves a discharge capacity of 115 mA h g(-)(1) and an energy density of 540 Wh kg(-)(1) over 500 cycles. These findings underscore LiBF4's dual role in protecting LNMO cathodes and Li metal anodes, highlighting the critical role of additives in CEI development for advanced lithium-metal batteries.

Nitinol (NiTi) is well known for its corrosion resistance, shape memory effect, superelasticity, and biocompatibility, whereas Titanium (Ti) is well known for its high specific strength, corrosion resistance, and biocompatibility. The bimetallic joint of NiTi and Ti is required for applications that require tailored properties at different locations within the same component, as well as to increase design flexibility while reducing material costs. However, because of the formation of brittle intermetallic phases, connecting NiTi and Ti is difficult. In the present study, a systematic experimental investigation is carried out to develop NiTi-Ti bimetallic joint using wire arc additive manufacturing (WAAM) for the first time and to evaluate its microstructure, mechanical properties, martensitic transformation, and actuation behavior in the as-built condition. The defect-free joint is obtained through WAAM and microstructural studies indicate the formation of intermetallics at the NiTi-Ti interface leading to higher microhardness values (600 HV). Shape recovery behavior and phase transformation temperature were also enhanced in comparison to NiTi. An improved actuation and bending angle recovery is observed in comparison with NiTi. The present study lays the way for the use of WAAM in the construction of NiTi and Ti bimetallic structures for engineering and medicinal applications.

A synergistic stabilization effect in a Nb-doped P2-type single crystal cobalt-free layered oxide cathode material, offering remarkable cycling stability and high-power performance for Na-ion batteries have unveiled in this study. The introduction of Nb in the transition metal layer not only reduces the electronic band gap but also enhances electronic conductivity and mitigates ionic diffusion energy barriers. The induction of a robust Nb-O bond expedites electron and Na+ transfer, contributing to the stabilization of the host structure is further confirmed through the density functional theory calculations, including electron localization function (ELF) and crystal orbital Hamiltonian population (COHP). To the best of our knowledge, this study is the first to demonstrate a homogeneous distribution of niobium throughout the single crystal, specifically doped at the nickel site within the bulk, without inducing atomic-scale surface reorganization. The presence of single crystals improves various kinetic factors, demonstrating the profound correlation between structural defects and chemical proliferation, thereby reducing the evolution of oxygen gas. The P2-type Nb-doped single crystal cathode (Na0.67Ni0.31Mn0.67Nb0.02O2) exhibits remarkable capacity retention, >95% after 100 cycles at 0.1 C and >90% after an extended cycling of 2000 cycles at 1 C. Practical assessments in complete cell setups with a pre-sodiated hard carbon anode further validate the material's viability, showcasing capacity retention of over 93% after 100 cycles in a coin cell and approximately 89% in a pouch cell format. This comprehensive study establishes the transformative potential of Nb-doped single crystal cobalt-free P2-type layered oxide cathode materials, marking a significant advancement in sodium-ion battery technology.