Interphase Properties Research Articles

Three-Dimensional Carbon Foam Modified with Mg3N2 for Ultralong Cyclability of a Dendrite-Free Li Metal Anode.

Uncontrolled growth of lithium dendrites and huge volume change during the lithium plating/stripping process as well as poor mechanical properties of the solid electrolyte interphase (SEI) are key obstacles to the development of a stable Li metal anode. Here, an ultralight Mg3N2-modified carbon foam (CF-Mg3N2) was fabricated as a collector to address these issues. The calculated results show that the CF-Mg3N2 composite is relatively stable in terms of energy. Based on the synergistic effect of the three-dimensional skeleton and the lithiophilic nature of Mg3N2, homogeneous lithium deposition/stripping was realized around the foam carbon skeleton with an extremely low nucleation overpotential (∼9.3 mV) and high retention of Coulombic efficiency (99.3%) as well as long cyclability (700 cycles and 3000 h in half and symmetrical cells, respectively). Meanwhile, Mg3N2-CF@Li//LiFePO4 full cells also showed better rate capability and more stable cycling capability than CF@Li//LiFePO4 and Li//LiFePO4 cells, exhibiting extreme practicality. Accordingly, the design concept mentioned in this work provides a far-reaching influence on the development of a stable Li metal anode.

Interphase Engineering for Stabilizing Ni-Rich Cathode in Lithium-Ion Batteries by a Nucleophilic Reaction-Based Additive.

Ni-rich cathode materials are considered promising candidates for next-generation lithium-ion batteries because of their high energy density and low cost. However, interphase failure at the surface of Ni-rich cathodes negatively impacts cycling performance, making it challenging to meet the requirements of long-term applications. In this study, a strategy is developed to improve interphase properties through introduction of a nucleophilic reaction-based additive, using an appropriate amount of the inducer lithium isopropoxide (LIP) in the commercial electrolyte to achieve long-term cycling stability of Li||LiNi0.83 Co0.11 Mn0.06 O2 (NCM83) cells. This strategy enables Li||NCM83 cells to maintain a capacity of 148.7 mAh g-1 with a retention of 83.3 % even after 500 cycles. This outstanding cycling stability is attributed to a robust cathode-electrolyte interphase (CEI) constructed on NCM83 surface LIP-induce ring-opening polymerization of ethylene carbonate (EC). As a result, the organic-inorganic components of the CEI effectively constrain gas evolution and the corresponding phase transformation behavior. Furthermore, the CEI also suppresses microcrack formation and eventually sustains the Ni valence and coordination environment at high voltage.

Stabilizing cathode-electrolyte interphase of LiNi0.5Mn1.5O4 high-voltage spinel by blending garnet solid electrolyte in lithium-ion batteries

This work presents a strategy of blending Li6.7La3Zr1.7Ta0.3O12 (LLZT) garnet solid electrolyte into LiNi0.5Mn1.5O4 (LNMO) high-voltage spinel cathode to enhance electrochemical performances and stabilities of electrode/electrolyte interphase layers in full-cells. Among a series of samples, 5 wt% LLZT blended LNMO delivered improved capacity, cycle life, and rate capability compared with a bare LNMO. The improvement mechanism of LLZT blended cathode can be explained in two folds. First, LLZT contacts with LNMO and improves Li+ transport properties of the cathode-electrolyte interphase (CEI) layer, as evidenced by electrochemical impedance spectroscopy (EIS) and distribution of relaxation time (DRT) analyses. Second, LLZT can scavenge moisture/proton in the electrolyte, oxidative decomposition products from the electrolyte, and suppress the degradation of CEI and solid-electrolyte interphase (SEI) layers during extended cycles, as evidenced by X-ray photoelectron spectroscopy (XPS). As a result, the 5 wt% LLZT blended LNMO cathode delivered a stable electrochemical performance even in the presence of 5000 ppm moisture (and thus HF) in an electrolyte. In contrast to the traditional surface coating methods, the solid-electrolyte blending approach is cost-effective, manufacturing/environmentally friendly, and thereby can serve as a practical pathway for improving the performances and stability of current battery cells for EV and small electronics.

Interface Manipulation of Composite Solid Polymer Electrolyte with Polydopamine to Construct Durable and Fast Li+ Conduction Pathways

Taking advantage of light weight, flexibility, and flame retardancy, solid polymer electrolytes (SPEs) provide a feasible solution to these safety concerns and to the enhancement of energy density for lithium-ion batteries (LIBs). However, the development of SPEs is still restricted by low ionic conductivity. Herein, we develop a type of SPE filler built by flower-like Co3O4 microspheres as a lithiophilic backbone and polydopamine (PDA) as a multifunctional coating for the engineering of the interphase properties of the polyether-based SPEs. The hierarchical structure of Co3O4 affords large interfacial contact area with SPEs and effectively suppresses the regular crystallinity of poly(ethylene oxide) (PEO) segments. Moreover, the PDA coating layers with diverse surface functionalities serve as a versatile mediator to finely tune ionic distribution and transport behavior via multiple Lewis acid–base interactions. We uncover the interphase characterizations and their synergistic effects to enhance Li+ conductivity and mechanical/electrochemical stability. This study provides intriguing alternatives for developing composite solid polymer electrolytes (CPEs), for which we further demonstrate the potential application of Co3O4@PDA-based CPEs in all-solid-state LIBs.

Analytical and parametric analysis of interface stress behaviour in nanoclay/polymer composite

Nowadays, nanoclay-reinforced polymers are one of the most widely used nanocomposites due to their high aspect ratio, higher contact area and their unique properties. These composites are used in a number of industrial applications, such as construction (building sections and structural panels), automotive (gas tanks, bumpers, interior and exterior panels), chemical processes (catalysts), pharmaceutical (as carriers of drugs and penetrants), aerospace (flame retardant panels and high performance components), food packaging and textiles, etc. Their interphase properties are essential for determining their proper design and safety application when applying large mechanical loads on them. In this work, a parametric analysis is performed to investigate how the change in the interphase properties influences the interphase shear stress (ISS) and interphase peel stress (IPS) in a nanoclay/polymer nanocomposite structure, subjected to axial load. The two-dimensional (2D) stress-function method is applied, which results in obtaining an analytical solution for ISS and IPS. The implemented parametric analysis shows how varying of the interphase mechanical properties (Young's modulus and Poisson's ratio) and their geometric properties (thickness and length) influence the value of the model interphase stresses. It was found, that increasing the value of Young modulus of the interphase does not change significantly the value of the model ISS, as well as the value of IPS, in the considered nanoclay/polymer structure. On the other hand, increasing the value of the interphase layer thickness becomes important for the value of ISS and IPS after 25nm. It turned out, that the interphase layer length is the most appreciable parameter, influencing both the model ISS and IPS. The obtained results could be useful for the proper design and safety application of similar nanoclay/polymer composites in industry.

From lithium to emerging mono- and multivalent-cation-based rechargeable batteries: non-aqueous organic electrolyte and interphase perspectives

Similarities and distinctions between lithium-based batteries and other emerging mono- and multi-valent cation-based batteries are comprehensively discussed, with focus on key parameters, which determine the properties of electrolyte and interphases.

Ionic conductivity and mechanical properties of the solid electrolyte interphase in lithium metal batteries

Energy Materials is an interdisciplinary international open access, online journal dedicated to communicating recent progresses related to materials science and engineering in the field of energy conversion and storage. The journal publishes Articles, Communications, Mini/Reviews and Perspectives with original research works focusing on the challenges of sustainable energy for the future.

The role of ion solvation in lithium mediated nitrogen reduction.

Since its verification in 2019, there have been numerous high-profile papers reporting improved efficiency of lithium-mediated electrochemical nitrogen reduction to make ammonia. However, the literature lacks any coherent investigation systematically linking bulk electrolyte properties to electrochemical performance and Solid Electrolyte Interphase (SEI) properties. In this study, we discover that the salt concentration has a remarkable effect on electrolyte stability: at concentrations of 0.6 M LiClO4 and above the electrode potential is stable for at least 12 hours at an applied current density of -2 mA cm-2 at ambient temperature and pressure. Conversely, at the lower concentrations explored in prior studies, the potential required to maintain a given N2 reduction current increased by 8 V within a period of 1 hour under the same conditions. The behaviour is linked more coordination of the salt anion and cation with increasing salt concentration in the electrolyte observed via Raman spectroscopy. Time of flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy reveal a more inorganic, and therefore more stable, SEI layer is formed with increasing salt concentration. A drop in faradaic efficiency for nitrogen reduction is seen at concentrations higher than 0.6 M LiClO4, which is attributed to a combination of a decrease in nitrogen solubility and diffusivity as well as increased SEI conductivity as measured by electrochemical impedance spectroscopy.

Impact of in coin cell atmosphere on lithium metal battery performance

Research on lithium metal as a high-capacity anode for future lithium metal batteries (LMBs) is currently at an all-time high. To date, the different influences of a highly pure argon glovebox (GB) and an industry-relevant ambient dry room (DR) atmosphere have received little attention in the scientific community. In this paper, we report on the impact of in coin cell atmosphere (ICCA) on the performance of an LMB as well as its interphase characteristics and properties in combination with three organic carbonate-based electrolytes with and without two well-known interphase-forming additives, namely fluoroethylene carbonate (FEC) and vinylene carbonate (VC). The results obtained from this carefully executed systematic study show a substantial impact of the ICCA on solid electrolyte interphase (SEI) resistance (RSEI) and lithium stripping/plating homogeneity. In a transition metal cathode (NMC811) containing LMBs, a DR ICCA results in an up to 50% increase in lifetime due to the improved chemical composition of the cathode electrolyte interphase (CEI). Furthermore, different impacts on electrode characteristics and cell performance were observed depending on the utilized functional additive. Since this study focuses on a largely overlooked influential factor of LMB performance, it highlights the importance of comparability and transparency in published research and the importance of taking differences between research and industrial environments into consideration in the aim of establishing and commercializing LMB cell components.

The nature and suppression strategies of interfacial reactions in all-solid-state batteries

Properties of interphases formed between the cathode and the sulfide solid electrolyte and interfacial failure mechanisms.

Magnetic, mechanical, electrical properties and coupling effects of particle reinforced piezoelectric polymer matrix composites

The 0-3 polymer-based magnetoelectric (ME) composites have the advantages of easy preparation, low cost, good flexibility, environmental friendliness and biological affinity, etc., and have a wide range of applications prospect in the biomedical field, such as the biological microelectronics, nanomedicine technology treatment, bone tissue healing and so on. The ME performance of this composite is jointly contributed by the properties of its component and microstructure. In this work, considering the impact of interphase effect, and the relationship between the effective properties of 0-3 ME composites and its microstructure is established, and the expressions of the Young's modulus, permeability, dielectric coefficient, piezoelectric coefficient, piezomagnetic coefficient and ME coefficient are obtained respectively. The effects of interphase properties and particle sizes on the effective properties of ME composites are discussed. By comparison, our theoretical results are in good agreement with experimental data. Then the influence of some factors on its effective performance is discussed. The results show that the effective properties of 0-3 ME composites are strongly dependent on the volume fraction ratio and size of the particles, the applied magnetic field. There is an optimal volume ratio and magnetic field to maximize ∂ α E 33 /∂ H 3 .

Tailoring solid-electrolyte interphase and solvation structure for subzero temperature, fast-charging, and long-cycle-life sodium-ion batteries

The sluggish Na+ reaction kinetics with carbon materials limits the fast-charging capability, Coulombic efficiency, and cycle life of sodium-ion batteries, especially at low temperatures. Herein, free-standing carbon nanofiber films, with controllable crystallinity and surface chemistry, are used as a platform to investigate the correlation between Na+ reaction kinetics, storage mechanism, and electrolyte environment. The ion solvation effect and solid-electrolyte interphase (SEI) properties determine the kinetics and storage mechanism. A strong Na+-solvent interaction, such as Na+-diglyme, tends to form a “pseudo-SEI” layer dominated by anion decomposition, enabling fast Na+-solvent co-intercalation kinetics. Tuning the SEI chemistries by pre-cycling in the weakly solvated electrolyte (e.g., ester electrolyte), the intercalation capacity rapidly disappears due to the high energy barrier for Na+ transport. Such mechanistic insights allow us to develop the optimal combination of electrode materials and electrolyte chemistry to achieve high initial Coulombic efficiency, ultra-long cycle life under fast charging, and excellent low-temperature performance.

Lithium-Ion Transport through Complex Interphases in Lithium Metal Batteries.

Lithium metal is one of the best anode candidates for next-generation batteries. However, there are still many unknowns regarding the structure and properties of the solid electrolyte interphase (SEI) formed due to electron transfer reactions between the Li metal surface and the electrolyte. In addition, because of the difficulties to study amorphous and dynamic phases and interphases, there are many questions about the ion diffusion mechanism through complex multicomponent materials and interphases. In this study, using first-principles theory and computation, we focus on developing a better understanding of the ion motion mechanisms in the vicinity of a SEI formed when a seed Li2O or LiOH cluster nucleates on the Li metal surface. We study the role of charge transfer at the interface between charged surfaces and the electrolyte, and we investigate the evolution of inhomogeneous Li metal deposits present in the neighborhood of the SEI nuclei, aiming to fundamentally understand how these events modify the ion transport through complex electrochemically active materials.

Effect of interphase thickness and fiber diameter on elastic properties of composites using multi-scale modelling

Composite materials are the largely used engineering materials in aerospace and automobile industries due to their high specific strength and high specific stiffness. The composites’ properties are essential for the design and development of the machine parts. They vary with fiber content, fiber properties, matrix properties, and type of manufacturing process. More experiments are required to obtain the properties and the best combination of fibers and matrices. However, several analytical methods are available to find the properties of the composite to avoid the number of experiments. In the present study, the properties of CFRP, GFRP, Amino-functional multi-walled carbon nano-tubes (CNT) added CFRP, CNT added GFRP composites have been calculated using the properties of fiber, interphase between fiber and matrix, matrix, and CNT. The properties of CNT added epoxy are obtained using the Halpin-Tsai equation in the first stage. In the second stage, the properties of interphase are calculated using the properties of CNT added epoxy and fiber properties. In the third stage, the properties of CFRP and GFRP are calculated using three phase constitutive model by considering the properties of fiber, interphase, and CNT added matrix. The properties are calculated at fiber diameters: 8 μm and 14 μm while varying the fiber volume fraction (%): 0 to 70%, interphase thickness: 50 nm to 500 nm, the weight fraction of CNT (%) added in epoxy: 0 to 5%. The addition of CNT has improved the elastic properties of CFRP and GFRP. The elastic properties of the composites are improved significantly with an increase in the interphase thickness.

Revealing the High Salt Concentration Manipulated Evolution Mechanism on the Lithium Anode in Quasi-Solid-State Lithium-Sulfur Batteries.

Lithium-sulfur batteries are promising candidates of energy storage devices. Both adjusting salt/solvent ratio and applying quasi-solid-state electrolytes are regarded as effective strategies to improve the lithium (Li) anode performance. However, reaction mechanisms and interfacial properties in quasi-solid-state lithium-sulfur (QSSLS) batteries with high salt concentration are not clear. Here we utilize in-situ characterizations and molecular dynamics simulations to unravel aforesaid mysteries, and construct relationships of electrolyte structure, interfacial behaviour and performance. The generation mechanism, formation process, and mechanical/chemical/electrochemical properties of the anion-derived solid electrolyte interphase (SEI) are deeply explored. Li deposition uniformity and dissolution reversibility are further tuned by the sustainable SEI. These straightforward evidences and deepgoing studies would guide the electrolyte design and interfacial engineering of QSSLS batteries.

Multiphase approach for calculation of tunneling conductivity of graphene-polymer nanocomposites to optimize breast cancer biosensors

A multiphase approach for the estimation of the electrical conductivity of graphene-based products from the properties of graphene, tunnels, and interphase is proposed. First, a simple model estimates the conductivity of interphase around the nanosheets, and subsequently, the conductivity of pseudoparticles containing graphene, tunnels, and interphase is estimated. Finally, a progressed model estimates the conductivity of the systems containing a polymer and pseudoparticles. The predictions of the multiphase technique were evaluated through comparison with experimented values and by parametric analyses. The predictions showed good agreement with the experimental values. Furthermore, the results of parametric studies supported the correctness of the multiphase technique. Thin and large graphene nanosheets can increase the conductivity to 0.14 S/m, and a high filler concentration and the presence of large tunnels could enhance the conductivity to 50 S/m. The maximum conductivity of 0.016 S/m is gained by an interphase depth of 10 nm and a filler conduction of 2.5 × 105 S/m. The developed model can be used for optimizing breast cancer biosensors since the conductivity is the main factor for detection.

An in-situ microscale investigation into the fracture of wood-adhesive interphase by nanoindentation

• Micropillar compression accompanied by FEA simulation was applied to investigate the fracture of wood-adhesive interphase. • Yield strength of microscale wood-adhesive interphase was contingent with the interpenetrating polymer networks (IPNs). • A crack-dominated fracture mode was found when compressing the wood-adhesive interphase comprising cell wall and adhesive. Green timber high-rises now taking off raises the desire to improve the mechanical performance and durability of engineered wood-based composites. It requires an in-depth understanding of the fracture mechanism of wood-adhesive interphase. Nanoindentation (NI) analyses in conjunction with finite element analysis (FEA) were conducted in this work to reveal the fracture behaviors and static mechanical properties of microscale wood-adhesive interphases composed of different cell wall layers and phenol–formaldehyde (PF) adhesive. Results revealed the evident cracks and bending in microscale wood-adhesive interphase, which originates from the stress concentration at the interfacial interlock of the cell walls and PF adhesive. Deformation of compound middle lamella (CML) located far from the bond line was prior to other microscale wood-adhesive interphases. Prolongation of cracks contributes to the fracture of wood substrates, and brittle fracture of adhesive leads to the deconstruction of wood-adhesive interphase. Results also demonstrated that compact interpenetrating polymer networks (IPNs) impart the corresponding wood-adhesive interphase with the favored yield strength (281 MPa) because of the improved stress transferring. Therefore, building compact IPNs is beneficial for fabricating a strengthened and toughened wood-adhesive interphase in engineered wood-based composites.

From Additive to Cosolvent: How Fluoroethylene Carbonate Concentrations Influence Solid–Electrolyte Interphase Properties and Electrochemical Performance of Si/Gr Anodes

Silicon-containing anodes perform best when the solid–electrolyte interphase (SEI) accommodates the high volume changes of silicon particles, as this reduces side reactions and extends the cell lifetime. With this work, we investigate the influence of different fluoroethylene carbonate (FEC) electrolyte concentrations on the SEI composition and thickness and correlate these SEI properties to the electrochemical performance. Three electrolytes (i.e., 2FEC:98LP30, 20FEC:80DMC, and 50FEC:50DMC) are cycled with 9% Si/Gr anodes, and their SEIs are characterized postmortem using photoelectron spectroscopy (XPS). We propose a fitting model for the XPS results in which FEC decomposition yields −C–O, DO (1,3-dioxolan-2-one), −CO2Li, Li2CO3, and LiF. −C–O, DO, and −CO2Li are most probably incorporated in a cross-linked polymeric network. Due to its distinct chemical environments, detecting DO can be unambiguously linked to the presence of FEC decomposition products in the SEI. The presence of DO-type species in the C 1s spectra is correlated to the electrochemical performance: A higher retention in silicon activity was observed for the 20 and 50 vol % FEC-containing electrolytes, where FEC decomposition products (i.e., DO) were present even after 100 cycles. By contrast, when cycling in the 2FEC:98LP30 electrolyte, the silicon activity cannot be retained, and FEC decomposition products are barely detected after 100 cycles. We suggest that the presence of the −C–O-, DO-, and −CO2Li-containing polymeric network positively influences the SEI during silicon volume changes. Additionally, we show that the interaction of FEC and LiPF6 plays an important role in the formation of SiOxFy species.

The study of physical-chemical and gas methods of treatment in displacement of hydrocarbons

Poor efficiency of displacement coverage while applying the methods of physical-chemical and gas treatment of the deposit is predominantly associated with the issues of viscous fingering and interphase properties of displaced and displacing fluids. An effort is made in this work to study a perspective method of treatment of the deposit allowing providing intra-reservoir reaction of carbon-dioxide emission. The paper presents the results of experimental studies dedicated to the search of new methods of treatment of oil deposit with gas-fluid banks. A possibility of creating banks of gas-fluid systems in the process of reaction of alkaline agents with hydrocarbons containing active acid components is shown as well. A field method based on the effect of leveling of displacement front and increasing the coverage of poor-drainage areas of the layer due to the formation of gas-fluid systems in the reservoir conditions is offered.

Investigation of the Mechanical Properties for Polymer Reinforced by Nanoparticles with Considering Viscoelasticity of the Matrix

Investigation of the Mechanical Properties for Polymer Reinforced by Nanoparticles with Considering Viscoelasticity of the Matrix