Recent breakthroughs and perspectives of high-energy layered oxide cathode materials for lithium ion batteries

Ni-rich layered oxides (NRLOs) and Li-rich layered oxides (LRLOs) have been considered as promising next-generation cathode materials for lithium ion batteries (LIBs) due to their high energy density, low cost, and environmental friendliness. However, these two layered oxides suffer from similar problems like capacity fading and different obstacles such as thermal runaway for NRLOs and voltage decay for LRLOs. Understanding the similarities and differences of their challenges and strategies at multiple scales plays a paramount role in the cathode development of advanced LIBs. Herein, we provide a comprehensive review of state-of-the-art progress made in NRLOs and LRLOs based on multi-scale insights into electrons/ions, crystals, particles, electrodes and cells. For NRLOs, issues like structure disorder, cracks, interfacial degradation and thermal runaway are elaborately discussed. Superexchange interaction and magnetic frustration are blamed for structure disorder while strains induced by universal structural collapse result in issues like cracks. For LRLOs, we present an overview of the origin of high capacity followed by local crystal structure, and the root of voltage hysteresis/decay, which are ascribed to reduced valence of transition metal ions, phase transformation, strains, and microstructure degradation. We then discuss failure mechanism in full cells with NRLO cathode and commercial challenges of LRLOs. Moreover, strategies to improve the performance of NRLOs and LRLOs from different scales such as ion-doping, microstructure designs, particle modifications, and electrode/electrolyte interface engineering are summarized. Dopants like Na, Mg and Zr, delicate gradient concentration design, coatings like spinel LiNi_0.5Mn_1.5O₄ or Li₃PO₄ and novel electrolyte formulas are highly desired. Developing single crystals for NRLOs and new crystallographic structure or heterostructure for LRLOs are also emphasized. Finally, remaining challenges and perspectives are outlined for the development of NRLOs and LRLOs. This review offers fundamental understanding and future perspectives towards high-performance cathodes for next-generation LIBs.     

Improving hydrothermal performance of hybrid nanofluid in double tube heat exchanger using tapered wire coil turbulator

Tapered wire coil insert is proposed as a novel enhancer in the double tube heat exchanger and experimental studies on Al₂O₃ + MgO hybrid nanofluid flowing under the turbulent condition are performed to investigate the hydrothermal characteristics. Effects of using tapered wire coil turbulator and hybrid nanofluid on the hydrothermal behaviors are examined for different coil configurations (Converging (C) type, Diverging (D) type and Conversing-Diverging (C-D) type) and hybrid nanofluid inlet temperatures and volume flow rates. Results show that D-type wire coil insert promotes better hydrothermal performance as compared to C-type and C-D type. Nusselt number and friction factor of hybrid nanofluid using D-type, C-D type and C-type wire coil inserts enhance up to 84%, 71% and 47%, and 68%, 57% and 46%, respectively than that of water in tube without insert. The entropy generation of hybrid nanofluid is lower than that of base fluid in all cases. The thermal performance factor for hybrid nanofluid is found more than one with all inserts. The thermal performance factor is observed a maximum of 1.69 for D-type coil. The study reveals that the hybrid nanofluid and tapered wire coil combination is promising option for improving the hydrothermal characteristics of double pipe heat exchanger.     

3D HCN nanotexture with synergistic effect of nickel and hole scavengers for enhancing photocatalytic H2 production: Role of morphology and influential parameters

Well-designed three-dimensional (3D) nanotextures of graphitic carbon nitride (g-C₃N₄), synthesized using template free single step method and mediated with nickel as a noble free metal, for solar hydrogen production, has been investigated. The photoactivity was investigated in a slurry type continuous flow photoreactor system by using different influential parameters such as hole scavengers, diffusion effects, time, and mass transfer. Compared to bulk g-C₃N₄, H₂ yield was increased with 3D hierarchical carbon nitride (HCN) nanotexture. The H₂ evolution rate was reached to 1310 µmol g^?1 h^?1 with optimized 2 % Ni loading to 3D HCN. This H₂ evolution rate was 19.8 and 24.9 times higher than it was generated using 3D HCN and g-C₃N₄, respectively. The special interlayer opening, more light penetration and suppressed charge carrier recombination were the main contributors for this photoactivity enhancement. Among the different influential parameters, lower viscosity, higher number of protons and less diffusion effects were promising to give significantly higher H₂ production. The stability of nanotextures was entirely dependent on the attached reactants over the nickel reactive sites, which was more promising for Triethanolamine (TEOA) than using methanol. This newly developed low-cost 3D HCN can be promising in solar energy conversion and other energy applications.     

Breaking behaviour and interactions in maize and soybean meal while grinding of a hammer mill

The objective of the present study was to investigate whether mixing ratio of maize and soybean meal (SBM) affects the breaking behaviour during hammer-milling in terms of the nutrient properties and in vitro digestibility of fractionated particles. Mixtures of maize and SBM with different proportions (% Maize:SBM; 0:100, 25:75, 50:50, 75:25, 100:0) were hammer milled using a 2-mm screen. The obtained powder was sieved into seven fractions with size ranges from 0.149 to 1.190 mm. Results show that energy consumption of grinding mixtures increased from 3.8 to 48.4 kJ/kg with the maize proportion increasing from zero to 100%. Mixing proportion of maize and SBM showed significant effects on nutrient content of fractionated material. For hammer milled material <595 µm, the in vitro digestibility of crude protein (CP) and organic matter (OM) of fractionated material decreased with increasing particle size. Additionally grinding fractionated particles ≥595 µm over a 1-mm sized screen before in vitro digestion analysis increased the digestibility of OM and CP. Equivalent particle size (EPS) and geometric standard deviation (GSD) of hammer milled maize and SBM and their mixtures correlated better than geometric mean diameter (GMD) to OM and CP in vitro digestibility in a linear regression model. In summary, the mixing ratio of maize and SBM had a significant effect on the breaking behaviour of ingredients and in vitro digestibility of CP and OM of the isolated fractions. Mixing ingredients before grinding is suggested in terms of saving energy consumption. The GSD/EPS of ground material should be considered while studying the effects of particle size distribution on the in vitro digestibility of nutrients.     

Recent progress in bismuth-based high Curie temperature piezo-/ferroelectric perovskites for electromechanical transduction applications

Piezo-/ferroelectric materials with high Curie temperature (T_C) are widely needed in sensors, actuators and transducers which can be used for high-temperature (HT) electromechanical transduction applications. In recent years, remarkable progress has been made in bismuth-based piezo-/ferroelectric perovskite materials (BPPs). In this article, recent progress in high T_C BPPs is reviewed. This review starts with an introduction to HT piezoelectrics and their applications. A detailed survey is then carried out on bismuth-based perovskites (BPs) with high T_C. Material synthesis, doping effects and chemical modifications of the related solid solutions are examined. Based on this analysis, the structure–property relationship of these materials is established. In addition, recent developments of BPPs for HT electromechanical transduction applications are presented and evaluated. Lastly, some main existing issues are analyzed and their possible solutions are proposed. This article provides a comprehensive overview of the research and development of BPPs and offers some prospects towards making these materials a viable resource for the design and fabrication of electromechanical transducers with unique specifications, especially, high temperature, high frequency and high power, for a wide range of technological applications.     

Changes in the oxygen content,morphology, and microstructure of Mo-10Nb composite powders during mechanical alloying

The prefabrication of Mo-Nb composite powders is an effective way of improving the homogeneity of Mo-10Nb targets, which have broad application prospects in the photoelectric sensor industry. However, this aspect has been rarely addressed so far. Therefore, we prepared Mo-10Nb composite powders by mechanical alloying (MA), and investigated the effects of the experimental parameters such as the milling speed and duration on the particle morphology, size distribution, compositional homogeneity, crystallite size, inner strain, and oxygen content. High-quality Mo-10Nb composite powders with 3-μm spherical particles of narrow size distribution, homogeneous elemental distribution, and nanometric crystalline structure were obtained by implementing optimum MA parameters, viz., a milling speed of 250 rpm and duration of 36 h using an MITR QM-QX-4L omnidirectional ball mill. The mechanically alloyed Mo-10Nb composite powders were prone to oxidation when exposed to air, which led to a sharp increase in the oxygen content to ~5400 ppm. X-ray photoelectron spectroscopic analysis revealed the presence of Nb₂O₅, MoO₂, and MoO₃ on the surface of the Mo-10Nb particle. We believe that this study demonstrates an interesting strategy for the fabrication of high-quality Mo-10Nb targets.     

Investigation of the molecular state of 4-aminosalicylic acid in matrix formulations for dry powder inhalers using solid-state fluorescence spectroscopy of 4-dimethylaminobenzonitrile

Carrier-free method is an alternative approach for dry powder inhaler (DPI) formulations, which overcome poor drug mobility and distribution. Here we investigated the properties of an active pharmaceutical ingredient (API) within composite particles. We used highly-branched cyclic dextrin (HBCD) as the excipient matrix that was prepared using a spray-drying technique. 4-Aminosalicylic acid (4-ASA) and 4-dimethylaminobenzonitrile (DMABN) were selected as a hydrophilic second-line antitubercular agent and a surrogate for 4-ASA as a model compound, respectively. The spray-dried particles (SDPs) containing 4-ASA or DMABN with HBCD had geometric median diameters (D₅₀) of 2.34 ± 0.07 μm and 2.26 ± 0.10 μm, respectively. Further, the in vitro aerodynamic properties were similar for SDPs containing 4-ASA and DMABN with HBCD. To determine the properties of APIs within composite particles, we performed solid-state fluorescence spectroscopy of DMABN. As a candidate excipient, hydroxypropyl methylcellulose (HPMC) was compared to HBCD. We determined the intensity ratio of twisted intramolecular charge transfer (TICT) emission to locally excited emission within the excipient matrix environment. The HBCD matrix environment was better than HPMC to trigger a more robust TICT reaction of DMABN. A potent state-changing interaction of APIs occurred in the HBCD matrix environment versus another excipient environment.     

CFD modelling and simulation of an industrial scale continuous fluidized bed roaster

In the present work, computational fluid dynamics (CFD) based modelling of an industrial scale continuous fluidised bed roaster (FBR) has been carried out to study its performance at different operating conditions, so that the sulphide-sulphur content in the product is within 0.4% at the designed feed rate of 39.75 DMT/h. Eulerian-Eulerian multiphase model, considering four granular phases and one gas phase has been implemented to investigate the velocity and mass fraction profile of the particles in the FBR. The heat and species mass balance calculations have been performed external to CFD, by dividing the roaster into several sections. The conversion of ZnS to ZnO at various sections of the roaster has been estimated using reaction kinetics under isothermal condition (1203 K). The heat liberated and possible temperature rise at each section was predicted based on the heat of reaction and sensible heat of the solid and gaseous products. The CFD model was validated with the plant data for a feed rate of 36.5 DMT/h, air flow rate of 65,000 Nm³/h and O₂ content of 21%. The proposed model predicted the sulphide-sulphur content in the product to be 0.4% for the designed feed rate of 39.75 DMT/h, when the O₂ content in the inlet air was increased to 25%.     

Designing amorphous formulations of polyphenols with naringin by spray-drying for enhanced solubility and permeability

Naringin (NAR), a major flavanone (FVA) glycoside, is a component of food mainly obtained from grapefruit. We used NAR as a food additive to improve the solubility and permeability of hydrophobic polyphenols used as supplements in the food industry. The spray-dried particles (SDPs) of NAR alone show an amorphous state with a glass transition temperature (T_g) at 93.2 °C. SDPs of hydrophobic polyphenols, such as flavone (FVO), quercetin (QCT), naringenin (NRG), and resveratrol (RVT) were prepared by adding varying amounts of NAR. All SDPs of hydrophobic polyphenols with added NAR were in an amorphous state with a single T_g, but SDPs of hydrophobic polyphenols without added NAR showed diffraction peaks derived from each crystal. The SDPs with NAR could keep an amorphous state after storage at a high humidity condition for one month, except for SDPs of RVT/NAR. SDPs with NAR enhanced the solubility of hydrophobic polyphenols, especially NRG solubility, which was enhanced more than 9 times compared to NRG crystal. The enhanced solubility resulted in the increased membrane permeability of NRG. The antioxidant effect of the hydrophobic NRG was also enhanced by the synergetic effect of NAR. The findings demonstrated that NAR could be used as a food additive to enhance the solubility and membrane permeability of hydrophobic polyphenols.     

pH-responsive dual-functional hydrogel integrating localized delivery and anti-cancer activities for highly effective therapy in PDX of OSCC

As one of the most promising localized drug delivery systems for enhancing therapeutic efficacy and reducing systemic toxicity, supramolecular hydrogels self-assembled from natural products have recently attracted tremendous attention. However, the intricate drug loading process, limited drug entrapment efficacy, and lack of stimulus responsiveness considerably impede their potential for biological applications and raise the need for advanced hydrogel-based delivery systems. Therefore, the development of updated materials that integrate localized delivery and drug activity into a single system is extremely desired and has great potential to overcome the aforementioned shortcomings. In this study, a pH-responsive dual-functional isoG-based supramolecular hydrogel with both localized delivery and anti-cancer activity in one molecule is successfully developed in one pot by following a simple and green procedure. The isoguanosine-phenylboronic-guanosine (isoGPBG) hydrogel exhibits exceptional stability (more than one year), outstanding pH-responsiveness and excellent sustained release capability. Both in vitro and in vivo experiments demonstrate that the isoGPBG hydrogel not only shows acceptable biocompatibility and biodegradability but also significantly inhibit tumor growth (approximately 60% inhibition of tumor growth) and improve overall survival, especially in preclinical patient-derived xenograft (PDX) model of oral squamous cell carcinoma (OSCC). Therefore, the isoGPBG hydrogel, to the best of our knowledge, is the first example of pH-responsive dual-functional isoG-based supramolecular hydrogel integrating localized delivery and anti-cancer activity in one molecule. It is implied that the isoGPBG hydrogel could act as a smart dual-functional localized delivery system in the future for clinical cancer therapy.     

Immersed-boundary/soft-sphere method for particle–particle-fluid interaction in a viscous flow: An OpenFOAM solver

We developed a stable OpenFOAM solver for Immersed Boundary Method based on direct forcing and regularized delta function. The soft-sphere model and a lubrication model were implemented to consider particle–particle collision in a viscous flow. We proposed a fluid–structure interaction (FSI) coupling method to accurately calculate the fluid forcing term and particle velocity. Our solver was validated for fixed and moving bodies, including rotation. The accuracy of various FSI schemes was evaluated in predicting the solid and fluid flow behavior in a viscous flow. It was demonstrated that neglecting or simplifying the fluid momentum change affects the accuracy of the solid velocity and fluid flow dynamic; for higher solid-to-fluid density ratios, a larger deviation was predicted. Furthermore, the FSI schemes highly influenced the behavior of the formed vortices.The solver was validated to predict the effective restitution coefficient of particles in a viscous flow as a function of the Stokes number. We also thoroughly analyzed the dynamic flow behavior of colliding particles through the pressure and velocity field and fluid force. This analysis helped us accurately determine the rebound velocity of particles in case of high Stokes numbers when the effect of viscous force is significant.     

Influence of the solvent evaporation rate on the β-Phase content of electrosprayed PVDF particles and films studied by a fast Multi-Overtone QCM

A combination of an electrospray setup and a quartz crystal microbalance with dissipation monitoring (QCM-D) was employed to study the drying of droplets of poly(vinylidene fluoride) (PVDF) dissolved in dimethylformamide (DMF). A novel variant of the QCM was used, which interrogates the resonance frequency and the resonance bandwidth on four overtones at the same time, achieving a time resolution of 2 ms. This instrument allowed to elucidate the mechanism of β-phase formation in electrospray deposition of PVDF. When the distance between the nozzle and the substrate was small, the droplets landed in a partially wet state, as evidenced from an increase in the resonance bandwidth. No such increase in bandwidth was observed when the distance was large. From the flight time (milliseconds) and the drying time on the substrate (seconds), one concludes that drying in the plume is faster than drying on the substrate. IR spectra show that the β–phase content is close to 100 % for particles, which dried in the plume. It is less than 50 % for particles having dried on the substrate. Fast drying promotes the formation of the β-phase. Follow-up experiments with thicker films on steel substrates also show increased β-phase content for larger distances.     

Steel slag waste combined with melamine pyrophosphate as a flame retardant for rigid polyurethane foams

To explore the potential application of industrial waste, steel slag powder in combination with melamine pyrophosphate (MPP) was adopted to improve the flame retardancy of rigid polyurethane foam (RPUF). The incorporation of steel slag slightly reduced the thermal conductivity of the resulting flame-retardant RPUF samples. The addition of MPP and/or steel slag did not significantly alter the thermal stability in terms of T_-10% and T_max but did obviously increase the T_-50% value, suggesting the improved thermal resistance of the residues. The coaddition of MPP and steel slag into RPUF resulted in higher LOI values and lower peak heat release rates than the samples incorporating either MPP or steel slag alone. The superior flame retardancy could be attributed to MPP promoting char formation, which then acted as a barrier at the beginning of RPUF thermal decomposition; simultaneously, the thermally stable inorganics in the steel slag powder strengthened the thermal resistance of this char layer.     

Novel preparation approach with a 2-step process for spherical particles with high drug loading and controlled size distribution using melt granulation: MALCORE®

A novel approach for preparing drug-containing particles (DCPs) with controlled size distribution and high drug loading was developed using melt granulation. This approach comprises two steps. First, melting component adsorbed particles (MAs) were prepared by mixing and heating the melting components with a porous carrier using a high shear granulator. Second, DCPs were prepared by layering the drug on MAs using a fluidized bed rotor granulator. The time taken for both steps was within 30 min. Adding the polymer in the second step remarkably increased the viscosity of the mixture of melting components and the polymer. Therefore, DCPs could be successfully loaded with a high amount of drug (70% w/w). The particle size distribution of the DCPs was narrow, and it depended on that of the MAs. The flowability of the DCPs was excellent, and the sphericity was close to 1. A unique particle formulation mechanism was suggested based on the observation of DCPs using scanning electron microscopy. The manufacturing time and DCP characteristics were not affected by the manufacturing scale. In conclusion, we have successfully developed a highly efficient novel approach for preparing optimal DCPs through melt granulation, named “Melt Adsorption and Layering with Porosity Core” (MALCORE®).     

Metal-organic framework derived hexagonal layered cobalt oxides with {1 1 2} facets and rich oxygen vacancies: High efficiency catalysts for total oxidation of propane

A cobalt-based metal–organic framework was used as a precursor to synthesize Co₃O₄ catalysts exhibiting a hexagonal layered morphology by calcination at varying temperatures. Various characterization techniques, such as XRD, SEM, Raman, H₂-TPR, O₂-TPD and N₂ adsorption–desorption, were used to study the effects of calcination temperature on the grain size, surface area, and pore volume of the catalysts. The Co₃O₄ catalyst obtained by calcination at 350 °C (Co₃O₄-350) exhibited the highest catalytic activity for the total oxidation of propane. Furthermore, the small grain size and layered structure of Co₃O₄-350 allowed it to possess a high specific surface area, a highly exposed {1 1 2} facets, and abundant oxygen defects that facilitated a favorable low-temperature reducibility and oxygen mobility, thereby improving catalytic activity. This research offers a simple strategy for synthesis of Co₃O₄ with layered structure, highly exposed {1 1 2} facets and rich oxygen defects.     

Scalable production of glass flakes via compression in the liquid phase

A comprehensive study on controlled shape formation with high yield of three commercially relevant SiO₂-based amorphous glasses in a stirred media mill is presented. Stressing under well-controlled conditions leads to micron-sized amorphous glass flakes with high aspect ratios. This unique result is quite contrary to the fundamental observation that comminution processes generally result in irregular shaped particles. The influences of glass composition, processing time, stirrer tip speed and grinding media size on the obtained products have been investigated. The size and shape of the obtained glass flakes have been characterized by scanning electron microscopy and atomic force microscopy. The glass flakes exhibit thicknesses as low as 155 nm while the lateral dimensions are well within the micrometer range. Our study shows that particle size reduction occurs within the first hour of grinding. Afterwards plastic deformation of the fragments, which can be accompanied by densification of the glass network, leads to the formation and further thinning of the glass flakes. To demonstrate the quality and applicability of the glass flakes interference pigments were realized by a TiO₂ coating via an aqueous titration process. The presented approach offers a simple, convenient and fully scalable top-down method to produce flake-like particles from various silica glasses. The obtained flakes are suitable substrates for further modifications and applications and the process can be transferred to other materials and glasses with tailor-made chemical compositions.     

Screening of sugars and cyclodextrins as carriers in montelukast dry powder inhalers processed by spray freeze drying

The purpose of this study was to develop a site targeting montelukast sodium (MTK) microparticles as a respiratory drug delivery system using the spray freeze drying (SFD) process. A range of sugars and cyclodextrins (CDs) were screened as carrier in order to find compatible excipients for the preparation of dry powder inhalers (DPIs). The physical characteristics of collected powders were studied by scanning electron microscopy (SEM), laser light scattering, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The aerodynamic behavior of the particles was also assessed using twin stage impinge (TSI). In the presence of simple sugars as carriers, highly porous particles in irregular shapes were produced. The use of CDs resulted in the formation of spherical particles with high porosity. Among all carriers that were used during the preparation of powders, raffinose had the best aerodynamic behavior with a fine particle fraction (FPF) of 60 % in sugar groups, while the lowest FPF was related to trehalose as carrier. Powders containing CDs mostly showed proper aerodynamic behavior, especially in formulations containing alfa-cyclodextrin (A-CD), beta-cyclodextrin (β-CD), and highly branched cyclic dextrin (HBCD). Overall, data indicated that the CDs were excellent excipients for use with MTK for respiratory drug delivery.     

3D printing vertically: Direct ink writing free-standing pillar arrays

Over the last three decades, a variety of additive manufacturing techniques have gradually gained maturity and will potentially play an important role in future manufacturing industries. Among them, direct ink writing has attracted significant attention from both material and tissue engineering areas, where the colloidal ink is extruded and dispensed according to a pre-designed path, usually in the X-Y plane with suitable increments in the Z direction. Undoubtedly, this way of disassembling geometries, simple or complex, can facilitate most of the printing process. However, for one extreme case, i.e. pillar arrays, the size resolution can deviate from both nozzle and design if the common way of slicing and additive manufacturing is used. Therefore, a different printing path is required – directly depositing pillars in a converse gravitational direction. This paper gives multiple examples of printing viscoelastic colloidal ceramic and metal inks uniaxially and periodically into free-standing and height-adjustable pillar arrays. It is expected to inspire the additive manufacturing community that more versatile degrees of freedom and complex printing paths, not confined within only complex shapes, can be achieved by ink-based 3D printing.     

Size-dependent aerosol penetration through facemasks and respirators (FMRs) during simulated exhalation and cough

Despite a good understanding of the filtration properties of various face and nose coverings during aerosol inhalation, their effectiveness in reducing aerosol emitted by infected individuals during exhalation or coughing is not fully characterized. This paper presents experiments conducted using a silicone model of a standardized face for controlled flow patterns (steady flow, typical exhalation or flow pulses associated with coughing/sneezing) used to push test aerosols (0.5–20 μm) through valved or non-valved respirators, surgical masks and cloth masks. The aerosol characteristics determined during experiments allowed quantitative comparison of size-dependent aerosol penetration for different flow conditions. The results showed that only aerosols smaller than 8.5–10 μm more easily penetrated beyond the face coverings tested but their concentrations outside were significantly reduced. Calculations based on experimental data showed that the amount of emitted airborne particles that can be inhaled into the lower respiratory tract of bystanders was reduced 1.3–5.7 times compared to the case when the spreader does not use a mask. These results bring additional quantitative information on the role of selected masks and respirators in reducing aerosol emission that potentially contribute to the transmission of viral diseases, including COVID.     

Characterization of solid-electrolyte/active-material composite particles with different surface morphologies for all-solid-state batteries

In all-solid-state lithium-ion batteries (ASS-LIBs), the electrode structure is an important factor that determines the battery performance; in particular, the formation of contact interface between the active material (AM) and solid electrolyte (SE) is an important issue associated with ASS-LIBs. Although we previously reported the formation of interfacial contacts between AM and SE by dry coating, the influence of the surface morphologies of composite particles on the performance of ASS-LIB was not revealed. In this study, we investigated the effects of the surface morphologies of composite particles on the performance of ASS-LIB. The surface morphologies of composite particles changed from “discrete” to “continuous” as the dry coating progressed. The cell prepared with composite particles showed higher ionic conductivity due to well-percolated ionic path than that prepared with simple mixture. Comparing the composite particles with different surface morphologies, the cell prepared with discrete-coating particles showed lower internal resistance due to higher ionic/electrical conductivity than that prepared with continuous-coating particles. Further, the cells prepared with discrete- and continuous-coating particles showed the highest charge and discharge capabilities, respectively. The results suggest that the contact areas of AM-SE and AM-AM were critical structural factors for the discharge and charge rate capability, respectively.