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Aqueous zinc‐ion batteries (AZIBs) are one of the most promising systems for large‐scale energy storage, but their zinc metal anodes suffer from unsatisfactory stability and reversibility due to the uncontrollable Zn dendrite growth and undesirable side reactions. Herein, a ZnO‐anchored nitrogen‐doped carbon/Ti3C2Tx MXene composite (ZnO@NC/MXene) is developed as a protective layer onto the zinc anode, which establishes a zincophilic and hydrophobic interface. In the ZnO@NC/MXene layer, the nitrogen sites efficiently enhances the adsorption of Zn2+, the ZnO provides homogenous nucleation sites for Zn2+ deposition, and the highly conductive MXene ensures even electric field distribution, synergistically inhibiting the zinc dendrites. Additionally, the hydrophobic ZnO@NC/MXene layer suppresses side reactions by limiting contact between the Zn anode and active water. Therefore, the Zn electrode modified by the ZnO@NC/MXene layer shows remarkable stability with a cycle life of over 2600 h in Zn||Zn symmetric cell and outstanding reversibility with an average coulombic efficiency of 99.37 % for over 1000 cycles in Zn||Cu asymmetric cell. Coupled with V2O5 cathode, the full cell reveals excellent cycle stability of exceeding 1000 cycles at 4 A g−1. These results indicate the potential of the zincophilic and hydrophobic ZnO@NC/MXene as a promising interface layer for protecting Zn anode in AZIBs. [ABSTRACT FROM AUTHOR]

With advantages including high capacity, intrinsic safety and low cost, aqueous zinc‐ion batteries (AZIBs) are ideal electrochemical energy storage devices for large‐scale and portable energy storage. However, the development of AZIBs suffers from tricky challenges, such as the notorious Zn dendrite growth and severe parasitic reactions. Herein, as a low‐cost and nontoxic biomass, agar is adopted to construct an interface layer on Zn foil to mitigate side reactions and induce uniform Zn deposition on Zn anodes. The interaction between Zn2+ and polar functional groups of agar can regulate Zn2+ distribution and promote Zn2+ desolvation, thus simultaneously achieving homogenous Zn deposition and suppressed hydrogen evolution reaction. Meanwhile, SO42− anions are blocked from contacting Zn surface due to electrostatic repulsion, greatly restraining corrosion and passivation. Consequently, Zn||A‐Cu asymmetric cell operates normally for 590 cycles with an average coulombic efficiency of 99.5 %, suggesting good reversibility of Zn plating/stripping. Notably, A‐Zn symmetric cell exhibits a long lifespan of 1100 h at 2 mA cm−2. Furthermore, the A‐Zn||NVO full cell displays a superb capacity retention of 94.8 % after 3600 cycles at 5 A g−1. This work offers a novel interface modification method for constructing stable and dendrite‐free anodes of AZIBs. [ABSTRACT FROM AUTHOR]

Trap states in organic solar cells (OSCs) can capture free charges, leading to a reduction in current density and significant energy loss. Since charge collection is primarily dependent on the interface layer, minimizing trap states at interfaces can effectively suppress energy losses, a topic that has been rarely explored. Herein, an interface strategy is proposed by combining Me‐4PACz and PEDOT:PSS to mitigate the trap‐assisted nonradiative recombination at the hole transport layer (HTL). OSCs based on the Me‐4PACz/PEDOT:PSS exhibit reduced trap densities and low energy losses compared to devices fabricated with a single‐layer HTL. This reduction can be attributed to a lower nonradiative recombination rate during hole transport at the interface. Changes in the work function of the two interlayers due to contact result in the existence of a built‐in potential inside the composite interlayer, promoting charge collection and reducing energy loss from charge recombination. Furthermore, the composite HTL interface induces vertical phase separation of active layer, leading to significant improvements of the fill factor for OSCs. As a result, high power conversion efficiencies (PCEs) of 18.70% and 19.02% are achieved for binary all‐polymer solar cells and polymer donor/small molecule acceptor solar cells, respectively. [ABSTRACT FROM AUTHOR]

All‐solid‐state rechargeable batteries are regarded as one of the most promising next‐generation energy storage devices, while their cycling stability is still a great challenge due to the nonuniform lithium ion transportation and the loss of active lithium during cycling. Herein, a LiF embedded prelithiated graphite interface layer is designed and inserted between Li6PS5Cl solid electrolyte layer and graphite anode layer. The presence of LiF, C−F bonds and prelithiated graphite in this unique interface layer can facilitate uniform lithium ion migration and compensate the loss of active lithium, thus significantly improving the cyclic performances of both monopolar and bipolar all‐solid‐state lithium ion batteries. After 100 cycles at 0.1 C, the capacity retention increases from 58 % to 78.5 % for the monopolar LiNi0.5Co0.2Mn0.3O2|Li6PS5Cl|LiF@2.5 %Li@G|graphite all‐solid‐state lithium ion battery. Besides, the bipolar all‐solid‐state lithium ion batteries show a high discharge plateau of ~7.6 V with a capacity retention of 60.2 % after 190 cycles at 0.1 C. This work demonstrates the effectiveness of LiF embedded prelithiated graphite interface layer for improving the electrochemical performances of all‐solid‐state lithium ion batteries. [ABSTRACT FROM AUTHOR]

Ferroelectric hafnia is one of the most promising materials for next generation of non‐volatile memory devices. Several strategies have demonstrated to be of interest to improve its functional properties. Interface engineering, realized by the introduction of additional layer in the capacitor structure, is demonstrated as a promising strategy. However, interface layers can have multiple implications, such as changes in the chemistry of the interfaces and an increase of depolarization field, whose effects are difficult to discriminate. The role of HfO2 and ZrO2 capping is explored on polarization, retention, endurance, and leakage properties of Hf0.5Zr0.5O2 epitaxial films. In HfO2 capped films, lower polarization is observed, and endurance and retention are also comparably worse than in ZrO2 capped films. Complementary under illumination ferroelectric characterization and capacitance measurements indicate a reduction of defects and interface capacitance contribution in ZrO2 capped films. For both cappings, the interfaces with the Hf0.5Zr0.5O2 layer are shown to be compositionally sharp and the phase of Hf0.5Zr0.5O2 (HZO) grains is replicated on the capping layer, indicating that electrostatic effects prevail and that the use of interface layers with high permittivity, here ZrO2, is crucial to favor good functional properties. [ABSTRACT FROM AUTHOR]

Summary: The microstructure and behaviors of the interface layer around the nanoparticle are strongly related to the overall thermophysical properties of molten salt‐based nanofluids (MSBNFs). Understanding this link may enable the advanced heat transfer fluid (HTF) for concentrated solar power and other applications. In this study, a molecular dynamics (MD) model for solar salt (60 wt% NaNO3/40 wt% KNO3)‐SiO2 nanofluid system is developed to estimate the characteristics of the interface layer and their effects on the overall specific heat capacity (SHC) and effective thermal conductivity (ETC) of MSBNFs. The results show that the SHC and thermal conductivity (TC) of the interface layer in MSBNFs are, respectively, 1.44‐1.85 and 1.05‐1.97 times higher than those of pure solar salt. The SHC of the interface layer has a significant effect on the overall SHC of the MSBNFs, but the interface layer is not the dominant influencing factor for the ETC enhancement of MSBNFs and thus has less effect on the overall ETC. [ABSTRACT FROM AUTHOR]

Lamination technique is one of the most promising and effective approaches to produce flexible organic solar cells (OSCs), with the combination of high throughput and simultaneous encapsulation. In this study, flexible ITO‐free OSCs were successfully fabricated by lamination technique under the optimized temperature and pressure. It is found that the introduction of hole interface layer of PEDOT:MoO3 helps to improve both the film hydrophobicity and the carrier extraction. A high efficiency improvement of about 30% is obtained in the interface‐modified laminating flexible ITO‐free OSCs compared to the conventional laminated device. This work illustrates that anode interface engineering has a significant effect on the improvement of performance of roll‐to‐roll laminated and self‐encapsulated OSCs. [ABSTRACT FROM AUTHOR]

The thermomechanical behavior of polymer nanocomposites is mostly governed by interfacial properties which rely on particle–polymer interactions, particle loading, and dispersion state. We recently showed that poly(methyl methacrylate) (PMMA) adsorbed nanoparticles in poly(ethylene oxide) (PEO) matrices displayed an unusual thermal stiffening response. The molecular origin of this unique stiffening behavior resulted from the enhanced PEO mobility within glassy PMMA chains adsorbed on nanoparticles. In addition, dynamic asymmetry and chemical heterogeneities existing in the interfacial layers around particles were shown to improve the reinforcement of composites as a result of good interchain mixing. Here, the role of chain rigidity in this interfacially controlled reinforcement in PEO composites is investigated. We show that particles adsorbed with less rigid polymers improve the mechanical properties of composites. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 9–14 Poly(methyl methacrylate) (PMMA) chains with a lower local stiffness parameter than poly(2‐vinylpyridine) enhance the reinforcement of poly(ethylene oxide) (PEO) composites when they are used in coating the nanoparticles. This behavior of interfacially strengthened and thermally stiffened PMMA adsorbed nanoparticles is explained by the networking between interfacial layers, which is controlled by the molecular rigidity and overall conformation of the chains in buried interfaces. [ABSTRACT FROM AUTHOR]

Replacing the traditional PVdF(-HFP) electrode binder with water-soluble alternatives can potentially render electrode fabrication more environmentally benign. Herein, the surface layer formation of stored and cycled samples of two water-based Li4Ti5O12 composites employing either poly(sodium acrylate) (PAA−Na) or sodium carboxymethyl cellulose (CMC−Na) as binders are studied with X-ray photoelectron spectroscopy. In all three formulations, the surface layer composition formed upon storage differed notably from the solid-electrolyte interphase (SEI) layer formed on cycled samples. The surface layer under open-circuit conditions seems to originate mostly from the electrolyte salt (LiPF6) degradation. The comparison with cycled samples after 10 and 100 cycles shows a continuous build-up of an SEI layer on PAA−Na and PVdF-HFP electrodes. In contrast, on CMC−Na containing electrodes the SEI composition remains nearly unchanged. The results correlate well with the electrochemical behavior. [ABSTRACT FROM AUTHOR]

ABSTRACT Material layers at electrode/semiconductor interfaces are fundamental for the photovoltaic properties of polymer solar cells. The relationship between open-circuit voltage ( VOC) and the work function ( φ) of these interface layers is still a matter of debate. Simulations, together with experiments on over more than 20 cell architectures based on P3HT:PC60BM, enabled us to analyze the physical dependence of VOC on φ. In particular, when the work function of the contacts is well inside the gap we observe that performance depends strongly on even small variations of φ. On the other hand, when it approaches the energy levels of the semiconducting polymers, device operation becomes the most efficient and less sensitive to variations in φ. Furthermore, by varying the Gaussian density of states (DOS) of the active blend we were able to show that VOC performance depends significantly also on the DOS. Our study based on the simultaneous variation of transport layers represents a promising method to optimize the design and performance of polymer solar cells. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 690-699 [ABSTRACT FROM AUTHOR]

We consider a two-dimensional singularly perturbed transmission problem with two different diffusion coefficients, in a domain with smooth (analytic) boundary. The solution will contain boundary layers only in the part of the domain where the diffusion coefficient is high and interface layers along the interface. Utilizing existing and newly derived regularity results for the exact solution, we prove the robustness of an h p finite element method for its approximation. Under the assumption of analytic input data, we show that the method converges at an 'exponential' rate, provided the mesh and polynomial degree distribution are chosen appropriately. Numerical results illustrating our theoretical findings are also included. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013 [ABSTRACT FROM AUTHOR]

In order to study the effect of an interface layer on fatigue crack growth, a thin pure Al layer was sandwiched between two LY12 plates using explosive bonding. Experiment shows that as a fatigue crack approaches the interface a remote plastic zone appears in the soft Al layer. Energy dissipation in the interface leads to significant deceleration of crack growth rate. FEM analysis shows that crack arrest is associated with load and distance between the crack tip and the interface. The size of the plastic zone can be calculated and used to predict the reduction in crack growth rate. The predictions agree well with the experimental results. [ABSTRACT FROM AUTHOR]