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This study focuses on establishing and validating a method to accurately measure the in-plane thermal conductivity of very conductive thin films, such as single-crystal metals or semiconductors, 2D and nanostructured materials. By integrating both 2 ω and 3 ω measurements, the method is rendered insensitive to the superficial thermal boundary resistance of the insulating overlayer, enabling precise estimation of the in-plane thermal properties of conductive films grown on top of substrates or multilayer stacks. The proposed technique is applied to analyze the thermal conductivity of a silicon-on-insulator stack with a top layer consisting of a 340 nm thick film of monocrystalline silicon. Measurements are conducted within a temperature range spanning from 250 to 325 K. The results confirm the method's capability to correctly assess the thermal conductivity decrease of the silicon film compared to bulk value, demonstrating its reliability for the thermal characterization of conductive thin films. [ABSTRACT FROM AUTHOR]

As electronic devices continue to undergo miniaturization, the concomitant reduction in the size of semiconductor components presents significant challenges for thermal management at interfaces. Numerous studies have underscored graphene as an auspicious material for enhancing heat dissipation within integrated circuits, attributed primarily to its superior thermal conductivity. We have employed a molecular dynamics approach to examine the influence of various charge distributions on the thermal transport properties at the graphene–water interface. Specifically, this study explores how modifications in charge distribution at the interface impact thermal conductivity. The results show that comparing the interfacial graphene sheet modified with charge to the case without charge modification, the Kapitza resistance is significantly lower. In addition, the temperature difference at the graphene–water interface is smaller as the charge increases, and the thermal transport at the interface is easier. When the charge strengths of the modifications are the same, the thermal resistance of the diagonal distribution is smaller than that of the filled modification, and part of the reason for the ease of heat transport is due to the increase in interfacial mutual strength due to Coulomb forces. The other main reason is that when the charge reaches a certain strength (q = 0.8 e), an ordered water layer is created near the charge-modified graphene interface. Our study provides a method for designing solid–liquid interfacial heat transport properties by controlling and regulating the liquid stratification at the interface. [ABSTRACT FROM AUTHOR]

We study the effects of uniaxial pressure on the thermal conductivity between two nanoparticles using atomistic simulation. While the system is compressed, we analyze the evolution of contact area, the relative density, and the dislocation density. Lattice thermal conductivity is calculated by non-equilibrium molecular dynamics simulations at several stages of the compression. Despite the increment of dislocation defects, thermal conductivity increases with pressure due to the increase in relative density and contact radius. The behavior of the contact radius is compared with the Johnson–Kendall–Roberts (JKR) model. While there is good agreement at low strain, after significant plasticity, signaled by the emission of dislocations from the contact region, the discrepancy with JKR grows larger with the dislocation density. The results for thermal conductivity show good agreement with previous studies at zero strain, and a theoretical model is used to accurately explain its behavior vs strain-dependent contact radius. Both the Kapitza resistance and thermal resistance decrease with strain but with very different evolution. Simulations of a bulk sample under uniaxial strain were also carried out, allowing for a clear distinction between the role of compressive stress, which increases the conductivity, vs the role of dislocations, which decrease the conductivity. For the NP system, there is the additional role of contact area, which increases with stress and also modifies conductivity. An analytical model with a single free parameter allows for a description of all these effects and matches both our bulk and NP simulation results. [ABSTRACT FROM AUTHOR]

As electronic devices continue to advance toward higher integration, thermal management issues have become a bottleneck, limiting device performance at the nanoscale. In this study, we reveal the bistable structural characteristics of circular hole defects in few-layer graphene, exhibiting both adhered and separated states, through molecular dynamics simulations. We propose a mechanical model that considers the interplay between the bending energy and cohesive energy to determine the critical size of the hole defect, at which the structure transits between the adhered and separated states. We further demonstrate that strain engineering can adjust the interfacial thermal resistance by more than fivefolds, which drives the structure transit between bistable states. The strain effect on the interfacial thermal resistance of the structure can be accurately described using analytical models. These findings illustrate that strain engineering is an effective method for precisely controlling the interfacial thermal resistance in few-layer graphene and provide new insights into possible thermal switch applications. [ABSTRACT FROM AUTHOR]

The document discusses the integration of machine learning (ML) into thermal transport research, highlighting its transformative impact on understanding and controlling heat transfer processes. It features 31 papers categorizing ML applications into machine learning potentials, predicting thermal properties, design and optimization, data analysis, and tutorials. ML has enabled accurate simulations, precise property predictions, innovative system designs, and efficient data analysis in thermal transport research, showcasing the potential for further advancements in the field. Despite challenges like model transferability, data scarcity, and interpretability, the document emphasizes the promising future of ML in advancing thermal science and engineering. [Extracted from the article]

We investigated thermal management challenges in semiconductor devices that use fusion bonding, with a focus on measuring the thermal resistance of the bonded interface. Starting with two fusion-bonded silicon wafers, we thinned the top wafer to below 100 μ m and used frequency domain thermoreflectance to measure the effective thermal boundary resistance of the fusion bond. We established the measurement uncertainty with a multilayer thermal diffusion model, considering the effects of the top Si layer thickness and laser spot size. The thermal boundary resistance was measured to be 0.2 and 0.5 m 2 K/MW for two types of bonded wafers, with total SiO 2 film thicknesses of 200 and 470 nm at the fusion bond layer, respectively. We also created defects at the interface and imaged these defects with the thermal phase response at specific frequencies chosen according to a thermal model. The method described can be applied to other types of wafer-to-wafer or die-to-die bonding including direct, polymeric, and metallic bonds. [ABSTRACT FROM AUTHOR]

We outline a surface scattering kernel for rarefied gas flows through ideally ordered nanomaterials, such as high aspect ratio carbon nanotubes. The derived model allows for a comparison of the tangential momentum accommodation coefficient, and, hence, the total effective friction, for different species of gases as a function of the particle diameter. This surface kernel is incorporated with a Fokker–Planck model as an approximation to transport of a rarefied gas through ideally ordered carbon nanotubes. The results of this analysis predict that H 2 experiences higher friction in such systems in comparison with larger molecules such as C H 4 . The results are proposed as a potential explanation of the reduced gas transport of hydrogen gas in nanoporous systems. [ABSTRACT FROM AUTHOR]

Non-contact photothermal pump-probe methodologies such as Frequency-Domain Thermo-Reflectance (FDTR) systems facilitate the examination of thermal characteristics spanning semiconductor materials and their associated interfaces. We underscore the significance of meticulous measurements and precise error estimation attained through the analysis of both amplitude and phase data in Thermo-Reflectance (TR). The precision of the analytical estimation hinges greatly on the assumptions made before implementing the method and notably showcases a decrease in errors when both the amplitude and phase are incorporated as input parameters. We demonstrate that frequency-domain calculations can attain high precision in measurements, with error estimations in thermal conductivity (k), thermal boundary resistance (Rth), and thermal diffusivity (α) as low as approximately 2.4%, 2.5%, and 3.0%, respectively. At the outset, we evaluate the uncertainty arising from the existence of local minima when analyzing data acquired via FDTR, wherein both the phase and amplitude are concurrently utilized for the assessment of cross-plane thermal transport properties. Expanding upon data analysis techniques, particularly through advanced deep learning approaches, can significantly enhance the accuracy and precision of predictions when analyzing TR data across a spectrum of modulation frequencies. Deep learning models enhance the quality of fitting and improve the accuracy and precision of uncertainty estimation compared to traditional Monte Carlo simulations. This is achieved by providing suitable initial guesses for data fitting, thereby enhancing the overall performance of the analysis process. [ABSTRACT FROM AUTHOR]

A novel interfacial resistance-free (IRF) bifunctional camouflage (transparent and invisible) device is proposed in this paper. The thermal and electric conductivities of the shell and background are the same to eliminate the interfacial resistance. The IRF bifunctional camouflage device can operate in thermal–electric fields based on the neutral inclusion method. The distribution of isotherm and equipotential lines are studied quantitatively by the simulations. It is confirmed that the IRF bifunctional camouflage device with arbitrary natural materials can effectively achieve not only the invisible function but also the transparent function in thermal–electric fields. This method provides a window to the realization of bifunctions and the development of multi-physics fields. [ABSTRACT FROM AUTHOR]

The significance of interfacial thermal resistance in the thermal conductivity of nanofluids is not well understood, in part because of the absence of measurements of this quantity. Here, we study the interfacial thermal resistance for metal–oil nanofluids of interest as heat transfer fluids for concentrating solar power, using density functional theory and molecular dynamics simulations. Insights on the role of chemical interactions in determining the interfacial thermal resistance are revealed. The results presented here showcase a general picture in which the stronger the chemical interactions between species at the interface, the lower the associated interfacial thermal resistance. The implications toward nanofluid design are discussed. We show that, for this important family of metal–oil nanofluids, the interfacial thermal resistance values are low enough so that it is possible to afford a reduction in particle size, minimizing stability and rheological issues while still offering enhancement in the effective thermal conductivity with respect to the base fluid. [ABSTRACT FROM AUTHOR]

As renewable hydrogen energy serves for primary input of cyclic clean energy systems, environmental instability and fluctuations during energy conversion impose multiple challenges to the stable and efficient operation of proton exchange membrane water electrolyzer (PEMWE) cells. Herein, the performance and stability of platinum coated titanium (Pt/Ti) bipolar plates to withstand diverse environmental conditions (H 2 SO 4 pH = 1, 3, 5 at 60, 70 and 80 °C) and relatively high electrolysis potentials (0.6–1.8 V Ag/AgCl) were explored. The thickness of platinum coating was about 680 nm without obvious defects, which reduced the corrosion current density of Pt/Ti bipolar plates to 0.09 μA cm−2 in a simulated PEMWE environment with applied potential of 1.0 V Ag/AgCl for 10 h. Meanwhile, the value of interfacial contact resistance (ICR) of the Pt/Ti bipolar plates was measured as 1.5 mΩ cm2, showing no significant increase in high-level potentials tests under diverse environment. In addition, the influence of internal and external conditions to the electrolyzer stack on bipolar plates were discussed in detail, and the interrelated effects of pH values and applied potentials on the corrosion resistance of the Pt/Ti bipolar plates were established, especially in the range around the value of the water electrolysis potential. • Effects of pH and temperature conditions on Pt coating were reported. • Enhanced anticorrosion and conductivity of Ti bipolar plates was realized. • ICR of Pt/Ti was 3.5 mΩ cm2 after 10 h potentiostatic polarization at 1.8 V. [ABSTRACT FROM AUTHOR]

[Display omitted] Composite solid-state electrolytes (CSEs) exhibit the high ionic conductivity of ceramic electrolytes and the facile processing and good flexibility of polymer electrolytes, representing the most promising class of solid-state electrolytes for the industrialization of lithium batteries. Nevertheless, CSEs continue encountering substantial interfacial resistance, which impedes their practical deployment. In response to these issues, a Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 /poly(vinylidene fluoride) (LLZTO/PVDF) solid electrolyte membranes with a thickness of 25 μm were prepared by the doctor blade method. In situ polymerization of 1,3-dioxolane (DOL) at the electrolyte–electrode interface was initiated by lithium hexafluorophosphate (LiPF 6) and lithium difluoro(oxalate)borate (LiDFOB) dual-salts to produce poly(1,3-dioxolane) (PDOL). The presence of PDOL in LLZTO/PVDF@PDOL results in a high room temperature ionic conductivity of 3.578 mS cm−1. Moreover, the Li||LLZTO/PVDF@PDOL||LiFePO 4 (LFP) battery exhibits a discharge-specific capacity of 143 mAh g−1 and capacity retention of 81.7 % after 1000 cycles at 2 C, and the pouch cell with LLZTO/PVDF@PDOL achieved a high energy density of 190 Wh kg−1. The findings of this study may facilitate the industrial application of CSEs. [ABSTRACT FROM AUTHOR]

Li metal batteries have been considered promising candidates for next-generation high-energy-density batteries due to their high theoretical capacity and low redox potential. However, the uneven Li flux causes the formation of Li dendrites, and "dead lithium" caused by the reaction with the liquid electrolyte hinders their practical application. Herein, a PVDF-HFP/LiTFSI polymer electrolyte was designed and fabricated to stabilize the interfaces of the Li metal anode. LiTFSI could participate in the formation of inorganic LiF-rich interphases through preferential reduction of TFSI− to effectively restrain the growth of lithium dendrites. The PVDF-HFP/LiTFSI polymer electrolyte coating showed a uniform morphology that induced uniform Li+ flux and dendrite-free Li deposition and stripping. Consequently, the polymer electrolyte-modified PE separator enabled a high rate and stable cycling performance of Li metal batteries. The PVDF-HFP/LiTFSI-modified PE separator showed an ionic conductivity of 5.7 × 10−4 S cm−1 with a lithium ion transference number of 0.47. Paired in Li‖Li symmetric cells, a long-duration cycling performance of 1100 h at 0.2 mA cm−2 was achieved. The polarization voltage remained at 0.013 V due to a low interfacial resistance of 70.6 Ohm cm2 in the Li metal anode. In Li‖LFP full cells, the polymer/ceramic electrolyte-modified separator enabled stable cycling over 700 cycles while maintaining 81% capacity retention after 500 cycles. Even at a high rate of 10C, the cell delivered a specific capacity of 74.7 mA h g−1. This work provides a new approach for developing high-performance Li metal batteries using a polymer/ceramic electrolyte-modified separator. [ABSTRACT FROM AUTHOR]

Highlights: Copolymer of divinylphenyl-acryloyl chloride copolymers (PDVB-co-PACl) is designed and synthesized to graft on the surface of aluminum nitride (AlN) to improve its hydrolysis resistance. AlN fillers functionalized by PDVB-co-PACl with the molecular weight of 5100 g mol-1 exhibits the highest hydrolysis resistance and the lowest interfacial thermal resistance. When the mass fraction of AlN@PDVB-co-PACl is 75 wt% and the grafting density of PDVB-co-PACl is 0.8 wt%, the λ for AlN@PDVB-co-PACl/PMHS composites is 1.14 W m-1 K-1 and maintains 99.1% after soaking in 90 °C deionized water for 80 h. A series of divinylphenyl-acryloyl chloride copolymers (PDVB-co-PACl) is synthesized via atom transfer radical polymerization employing tert-butyl acrylate and divinylbenzene as monomers. PDVB-co-PACl is utilized to graft on the surface of spherical aluminum nitride (AlN) to prepare functionalized AlN (AlN@PDVB-co-PACl). Polymethylhydrosiloxane (PMHS) is then used as the matrix to prepare thermally conductive AlN@PDVB-co-PACl/PMHS composites with AlN@PDVB-co-PACl as fillers through blending and curing. The grafting of PDVB-co-PACl synchronously enhances the hydrolysis resistance of AlN and its interfacial compatibility with PMHS matrix. When the molecular weight of PDVB-co-PACl is 5100 g mol−1 and the grafting density is 0.8 wt%, the composites containing 75 wt% of AlN@PDVB-co-PACl exhibit the optimal comprehensive performance. The thermal conductivity (λ) of the composite is 1.14 W m−1 K−1, which enhances by 20% and 420% compared to the λ of simply physically blended AlN/PMHS composite and pure PMHS, respectively. Meanwhile, AlN@PDVB-co-PACl/PMHS composites display remarkable hydrothermal aging resistance by retaining 99.1% of its λ after soaking in 90 °C deionized water for 80 h, whereas the λ of the blended AlN/PMHS composites decreases sharply to 93.7%. [ABSTRACT FROM AUTHOR]

[Display omitted] The electrochemical performance of lithium metal batteries (LMBs) was hampered by the uncontrolled growth of lithium (Li) dendrites. To address this issue, the extensive application of artificial solid electrolyte interphase (SEI) coatings on anode surfaces emerged as an effective solution. Electrospinning, as an innovative technique for fabricating artificial SEI layers on the surface of copper (Cu) foil, effectively mitigated Li volume strain during cycling. In this study, an electrospun organic–inorganic composite nanofiber membrane was in-situ fabricated on Cu foil, serving as an artificial SEI layer (CuWs) for anode-free LMBs (AF-LMBs) to enhance battery performance. Lithiophilic polyvinylpyrrolidone was used as the polymer matrix, and Cu nitrate served as the inorganic functional particles capable of in-situ redox reactions. The CuWs with their three-dimensional (3D) network structure accommodated electrode volume changes and suppressed Li dendrite growth during Li deposition and stripping. Additionally, CuWs facilitated the in-situ generation of Li nitrate (LiNO 3), which helped stabilize SEI layer and enhance Li utilization. The release sites of LiNO 3 on the nanofibers enabled the in-situ reduction of metallic Cu, providing nucleation sites for Li deposition and forming the 3D ion–electron hybrid conductive networks. This CuWs layer reduced interfacial resistance and nucleation barriers, promoting uniform Li+ distribution on the anode surface. Li-Cu cells incorporating CuWs exhibited remarkable cycling stability, enduring over 460 cycles at 1.0 mA cm−2 and 1.0 mAh cm−2 with an average Coulombic efficiency of over 98.6 %. In Li-poor cells, the LFP|PE|CuWs achieved stable cycling for more than 30 cycles at 1.0 C, with a capacity retention rate of 92.0 %. These findings demonstrated that the CuWs membrane significantly enhanced the electrochemical performance of Li-poor cells and provided a novel artificial SEI protective strategy for advanced AF-LMBs with high energy density. [ABSTRACT FROM AUTHOR]

Te2−/ZIS-V S in situ heterojunction with S-Scheme charge transfer mechanism was synthesized by replacing S2− with Te2− for atomic reconstruction and introducing S vacancies. The absence of interfacial resistance between the in situ heterostructures, combined with the presence of S vacancies, can significantly promote the photogenerated charge separation, surface electron enrichment and CO 2 adsorption/activation, and which effectively improve the photocatalytic CO 2 reduction activity. [Display omitted] • Ultrathin Te2−/ZIS-V S in situ heterojunction nanosheets synthesized by atomic-level substitution of homologous Te2− for S2− remodeling. • In situ heterostructure with gradient work function and no interfacial resistance can effectively enhance the charge separation efficiency. • In situ characterization and DFT indicate the formation of an S-Scheme heterojunction charge transfer mechanism. • Te2−/ZIS-V S exhibits enhanced CO 2 reduction activity and selectivity. • The evaluation results showed that most of the 17 impact categories showed low overall impact values and were environmentally friendly. Reconfiguration of in situ heterojunction composites without interfacial resistance by substitution of homologous anions for the formation of gradient work function differences inducing the formation of built-in electric field is an effective strategy to enhance the charge separation efficiency. Herein, Te2−/ZnIn 2 S 4 -V S (Te2−/ZIS-V S) in situ heterojunction was synthesized by substitution of Te2− ions for S2− in ultrathin ZIS containing S vacancies, which can significantly promote photogenerated charge separation, surface electron enrichment, and CO 2 adsorption/activation. The presence of S vacancies and adjacent Te2−/S2− double anions, the double active sites constructed by defect engineering promote the desorption of *CO molecules while inhibiting the protonation toward *CHO, which was more favorable for selective CO 2 photoreduction to CO. The experimental results showed that the CO yield of Te2−/ZIS-V S was significantly increased to 672.1 μmol g−1 h−1 compared with pristine ZIS (54.3 μmol g−1 h−1) and the CO selectivity was close to 83 %. Notably, the life cycle assessment (LCA) of Te2−/Znln 2 S 4 nanosheets with S-vacancy was performed. The evaluation results showed that most of the 17 impact categories showed low overall impact values and were environmentally friendly. Based on the results of this LCA, suggestions were put forward to further optimize the product to reduce carbon emissions. [ABSTRACT FROM AUTHOR]

This study investigates the development of pore-filling anion-exchange membranes (PFAEMs) for water-electrolysis applications. Ionomers using two different cross-linking monomers, namely hydrophilic C10 and hydrophobic C11, along with a common electrolyte monomer, E3, were compared in terms of through-plane ion conductivity, hydrogen permeability, mechanical and chemical stability, I-V polarization, and water-electrolysis durability. The results revealed that the E3-C10 PFAEM exhibited 40% higher OH− conductivity (98.7 ± 7.0 mS cm−1) than the E3-C11 PFAEM with a similar ion-exchange capacity. This improvement was attributed to improved separation of hydrophobic and hydrophilic domains, creating well-connected ion channels by the hydrophilic C10. Alkaline stability tests demonstrated that the E3-C10 retained higher ion conductivity compared to E3-C11, due to the absence of ether linkages and increased resistance to nucleophilic attack. During water-electrolysis operations, the E3-C10 PFAEMs showed 10% better durability and 87% lower hydrogen permeability, confirming their suitability for anion-exchange-membrane water electrolysis (AEMWE). Despite the higher ion conductivity of the E3-C10 PFAEM, performance was limited by interfacial resistance. It is suggested that ionomer-coated electrodes could further enhance AEMWE performance by leveraging the higher ion conductivity of the E3-C10. Overall, this study provides valuable guidance on strategies for utilizing pore-filling membranes in water electrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The performance and stability of different anionic salts in 2G for HC/Na half-cells are investigated. • The interfacial chemistry, interphasial properties and electrochemical kinetics are comprehensively studies. • The underlying side reaction and mechanism of different anionic salts with Na metal is elucidated. In hard carbon (HC) anodes, elucidating the relationship between the solid electrolyte interphase formation and the solvated Na+ co-intercalation mechanism is crucial, particularly considering different anionic salts in ether-based electrolytes. Here, we comprehensively explore the impact of different anionic salts on the electrochemical performance of HC/Na half-cell and elucidate the underlying mechanism through experimental studies and theoretical calculations. The surface morphology of the HC anode and its interphasial property are further investigated to evaluate the differences endowed by the presence of various anionic salts in diglyme (2G). The HC/Na half-cells with NaPF 6 -2G and sodium trifluoromethanesulfonate (NaCF 3 SO 3)-2G display superior electrochemical performance with faster kinetics and lower interfacial resistance than those with NaClO 4 -2G, sodium bis-(fluorosulfonyl) imide (NaFSI)-2G and sodium bis-(trifluoromethanesulfonyl) imide (NaTFSI)-2G. NaClO 4 -2G forms a relatively thick interphase layer with high resistance at the electrode/electrolyte interface owing to its insufficient stability. NaFSI-2G and NaTFSI-2G exhibit severe side reactions with Na metal, producing a thick interphase layer on the HC surface with high interfacial resistance from excess electrolyte decomposition, thus deteriorating the electrochemical performance. In summary, the study on the stability of different anionic salts in ether-based electrolyte for the HC anode with the intercalation mechanism provides valuable insights for screening appropriate conductive salts for high-performance sodium-ion batteries, especially when considering Na metal counter/reference electrodes. [ABSTRACT FROM AUTHOR]

Surface modification of metallic bipolar plates is a crucial subject for the performance elevation of proton exchange membrane fuel cells (PEMFCs). In this work, a series of CrN coatings and CrN/Nb coatings were prepared on SS316L by DC magnetron sputtering technology with different deposition power of 80 W, 100 W, 150 W and 200 W. The results show that with the decrease of deposition power, the surface of CrN/Nb coating changes from loose porous to uniform and dense, and the columnar crystal structure changes from burly to fine, which improves the corrosion resistance and electrical conductivity of the coating. The corrosion current density decreases from 3.5 μA cm−2 of CrN/Nb-200 W to 0.39 μA cm−2 of CrN/Nb-80 W. The XPS results show that the intensity of O–Cr peaks decreases while the intensity of N–Cr peaks increases with the decrease of power, which also confirms that the coatings prepared at low power have better corrosion resistance. Furthermore, the corrosion current density of CrN/Nb-80 W coated SS316L is 0.39 μA cm−2, and the interface contact resistance at 1.4 MPa is 9.2 mΩ cm2, which are much lower than those of CrN-80 W coated samples (1.58 μA cm−2 and 16.3 mΩ cm2). After the constant potential polarization test, the Fe and Cr ion concentrations in the solution of CrN/Nb coated specimens were significantly lower than those of CrN coated specimens, which indicates that the CrN/Nb coating has better corrosion resistance. The applying of Nb transition layer endows the coating and substrate better adhesion (increased 48%), which can hinder the penetrating cracks to the substrate in the coating and improve the corrosion resistance. • CrN and CrN/Nb coatings were deposited on the SS316L alloy under different powers. • The surface morphology becomes uniform and compact with decreasing the deposit power. • Coatings prepared at lower power possess better corrosion resistance and lower ICR. • The addition of Nb transition layer improves the performance of CrN coating. • Nb addition can hinder the columnar crystals growth of CrN. [ABSTRACT FROM AUTHOR]

Addressing the challenges in solid oxide fuel cells (SOFCs) applications, this study develops efficient low-temperature cathode materials. The proton-conducting barium zirconate-based electrolyte BaZr 0·1 Ce 0·7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) shows excellent conductivity and stability, indicating significant potential in proton conducting SOFCs (H–SOFCs). A series of A-site defect-engineered (La 0·6 Sr 0.4) x Co 0.2 Fe 0·7 Nb 0·1 O 3-δ (LSCFN, x = 1, 0.95, 0.90) cathode materials were synthesized via the sol-gel method. The composite electrodes incorporating LSCFN and BZCYYb exhibited enhanced oxygen reduction reaction (ORR) performance. Results indicate that A-site defects significantly enhance electrocatalytic activity. At 750 °C, a single cell with a Ni-BZCYYb|BZCYYb|(LS) 0.90 CFN-BZCYYb configuration exhibited the lowest interfacial resistance (0.063 Ω cm2) and highest peak power density (0.933 W/cm2). Durability testing at 700 °C for 100 h under 0.3 A/cm2 showed excellent stability with negligible degradation, confirming the positive impact of A-site defects on ORR activity. The distribution of relaxation times (DRT) analysis provided insights into performance optimization. Thus, (La 0·6 Sr 0.4) 0.9 0 Co 0·2 Fe 0·7 Nb 0·1 O 3-δ -BZCYYb demonstrates excellent potential as an H–SOFC cathode material, advancing SOFC technology. • Synthesized (LS) x CFN (x = 1, 0.95, 0.90) cathodes with A-site defects. • Reached peak power density of 0.933 W/cm2 at 750 °C using (LS) 0.90 CFN-BZCYYb cathode. • Stable H–SOFC operation for 100 h at 700 °C, 0.3 A/cm2, with minor degradation. • A-site defects enhanced ORR kinetics, reducing interfacial resistance to 0.063 Ω cm2. • DRT analysis insights into electrochemical process optimization & cathode performance. [ABSTRACT FROM AUTHOR]

Li1.5Al0.5Ge1.5(PO4)3 (LAGP) is a promising solid-state electrolyte (SSE) for solid-state batteries but suffers from side reactions with Li metal resulting in cracking and interfacial resistance rise which hinders its practical application. Herein, in operando Raman spectroscopy was performed to gain insights into local chemical and structural transformations of the Cu/LAGP interface during cathodic polarization. [ABSTRACT FROM AUTHOR]

Short carbon fiber reinforced aluminum matrix composites exhibit suitable thermal conductivity and desirable coefficient of thermal expansion for electronic packaging applications. The interfacial bonding characteristics between carbon fibers and aluminum matrix play a crucial role in determining the performance of the composites. In the present study, the surface modification of carbon fibers and optimization of fabrication processing parameters were used to ameliorate the interface bonding and improve the properties of carbon fiber/Al composites. The electroless plating method was employed to deposit a nickel coating on the surface of carbon fibers. Aluminum matrix composites reinforced with 20∼50 vol.% uncoated or nickel-coated carbon fibers were fabricated by vacuum hot pressing technique. The microstructures, interface structures, relative density and thermal conductivity of the composites were systematically investigated. The results indicated that carbon fiber/Al composites with relatively high density of 98.9% and acceptable thermal conductivity of 218.1 W·m−1 K−1, as potential candidates for electronic packaging applications, were successfully fabricated. Through the application of nickel coating, the interfacial thermal resistance was effectively reduced by one order of magnitude derived from the experimental calculations using Maxwell-Garnett effective medium approach as a result of improved interface bonding. [ABSTRACT FROM AUTHOR]

Graphite (GR) is a commonly used two-dimensional filler with abundant sources and low cost. Its excellent electrical conductivity makes it widely used to prepare various conductive materials. However, its utilization in anti-corrosion materials is hindered by its extremely high conductivity, which pose significant challenges in material application. Nevertheless, its two-dimensional laminate structure serves as an effective filler for anti-corrosion applications. If the insulation properties of graphite can be enhanced, it will significantly broaden its applications in anti-corrosion coatings. The hydrolysis and condensation of tetraethyl orthosilicate (TEOS) and γ-methacryloxy propyl trimethoxy silane (MPS) were used to modify GR to improve its insulation. Additionally, this modification improved the compatibility between the filler and resin, reducing interfacial thermal resistance and thereby enhancing the thermal conductivity of the coating. The modified GR filler (SiO@GR) was added to epoxy resin (EPR) to prepare the composite coating (SiO@GR/EPR). When the SiO@GR content is 18 wt%, thermal conductivity can reach 0.67 W m−1K−1, and after soaking in 3.5 wt% NaCl solution for 7 days, the impedance modulus remains above 1.06 × 1011 Ω cm2. The synergistic effect of the physical barrier provided by two-dimensional fillers and the capacity enhancement of siloxane is thoroughly examined in relation to heat conduction and anticorrosive mechanisms. This study provides a simple approach to fabricating composite coatings with anti-corrosion and thermal conductivity performances. [ABSTRACT FROM AUTHOR]

In the frame of this work, we report a profound insight into the thermal conductivity (k) of aluminum nitride (AlN) thin films deposited on AlN-molecular beam epitaxy (MBE)/Si(111) and AlN-Kyma/Si(111) substrates at low temperatures (<200 °C) using reactive direct current magnetron sputtering (DCMS). Our concern is not on the thermal properties at the nanoscale, but rather on relating thermal macroscopic properties to the microstructure for submicronic to micronic AlN films. As the mean free path for AlN material is about 100 nm, the thickness of our films lies between 400 nm and 2 μm. The k measurements were conducted using the ultra-fast transient hot strip technique. It was found that the k values of the deposited films change depending on both the substrate type and the film thickness. For the 500 nm AlN thick film, k value was about 250 W m−1 K−1 for AlN-DCMS films grown on 10 nm AlN-MBE/Si against 90 W m−1 K−1 for those deposited on 200 nm AlN-Kyma/Si. The thermal boundary resistance has been computed equal to (0.25 ± 0.08) × 10−9 K m2 W−1 on 10 nm AlN-MBE/Si against (3.56 ± 1.50) × 10−9 K m2 W−1 on 200 nm AlN-Kyma/Si. Additionally, both pole figures and high resolution transmission electron microscopy confirm k results. In fact, pole figures confirm the good crystal quality of the film on both substrates, but HR-TEM analyses show that the AlN films grown on 10 nm AlN-MBE/Si template exhibit good crystalline quality with an epitaxial regrowth and abrupt interface compared to those obtained for 200 nm AlN-Kyma/Si. It also appears that the thermal boundary resistance plays a major role in the thermal properties of AlN films. [ABSTRACT FROM AUTHOR]

The significant interfacial resistance between solid electrolyte‐electrode interfaces is a major bottleneck for the practical application of solid‐state lithium batteries. This resistance is primarily caused by the formation of space charge layers (SCLs), resulting from the redistribution of ionic carriers at the interface between dissimilar materials with varying chemical potentials, which lead to insufficient carriers and sluggish lithium‐ion transport. In this study, a conjugated structure polymer is constructed through in situ polymerization onto the oxide electrolyte, forming charge‐rich SCLs on the organic/inorganic interface, and enabling the interfacial layer to maintain superior ion transfer and contact. The Li solid NMR spectra and computational study suggest that optimized SCLs offer effective pathways for Li+ conduction in the electrolyte, thereby enhancing the interfacial conduction. Furthermore, the designed electrolyte induces the formation of an inorganic‐rich interphase layer on the lithium anode, enabling rapid lithium‐ion transport and uniform Li deposition. Consequently, the lithium symmetric cell with this electrolyte operates for more than 5100 h, while LiFePO4/Li solid‐state batteries can stably cycle up to 800 times at 5 C. This interfacial modification strategy provides a new perspective for the rational design of the charge‐rich SCLs and advances the understanding of the SCLs inside the electrolyte. [ABSTRACT FROM AUTHOR]

Cubic‐garnet solid electrolyte has garnered significant attention in all‐solid‐state batteries (ASSBs) due to its ionic conductivity and chemical robustness against Li metal. However, the short‐circuit formation at low current density poses a significant obstacle with the main cause remaining ambiguous. Here, the lithium‐penetration mode originating from phase transformation is unveiled at the sintered pellet surface via mechanically induced lithiation. Mechanical stress applied during polishing under excess lithium content induces lithiation into the cubic‐garnet structure, leading to partial structural evolution into the tetragonal phase. This surface alteration induces current constriction, hindered by sluggish interfacial Li‐ion transport from the tetragonal phase, which exhibits low ionic conductivity, causing short circuits. By reducing mechanical stress, mitigating surface strain, and restoring the cubic phase, stable operation is ensured without short‐circuit formation in both Li symmetric and hybrid‐full cells. This insights illuminate the origin of lithium penetration related to phase transition at the surface of cubic‐garnet and pave the way for enhancements in ASSB development. [ABSTRACT FROM AUTHOR]

Dopability plays a pivotal role in determining the limit of carrier concentration and the chemical potential of semiconductor thermoelectric materials, which are directly related to the figure of merit. Here, the doping behavior and mechanism of cobalt (Co) in GeTe‐based thermoelectric materials are first investigated. According to theoretical calculations and tentative experiments, the extremely hard Co dopability in GeTe system is ascribed to the formation of an insoluble intermetallic phase in eutectics, even though the point defect formation energy and charge transition level indicate a 3at.% doping limit. A two‐step method is developed to synthesize (CoGe2)xGe0.85Sb0.10Te composited thermoelectric materials and use synchrotron technologies to investigate both average and local structures. CoGe2 nanoprecipitates are observed endotaxially and uniformly embedded in Ge0.85Sb0.10Te matrix, which acts as an electron reservoir to optimize carrier concentration without deteriorating carrier mobility, conceiving an ideal modulation doping scheme. Moreover, the phonon mismatch at the semi‐coherent CoGe2/Ge0.85Sb0.10Te interfaces gives rise to the Kapitza resistance to impede phonon propagation. The synergistic manipulation of electronic and thermal transport leads to a desirable figure of merit of 2.2 at 775 K and a conversion efficiency of 8.2% under a temperature difference of 420 K, representing a promising performance in this field and providing a benchmark workflow to design composited thermoelectrics. [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of CO 2 to ethylene was achieved by using metal–organic framework-derived Cu0/Cuδ+-based photocatalyst. The selectivity of the ethylene product reaches up to 90.2%, which is a record high among all the photocatalysts reported so far for photocatalytic CO 2 reduction. [Display omitted] • Photocatalysts were synthesized by reducing MOF precursors with NaBH 4 solution. • Photocatalytic CO 2 reduction to C 2 H 4 with high selectivity was achieved. • Structures of MOF precursors affect the type of products during photocatalysis. The highly selective conversion of CO 2 into valuable C 2 H 4 is a highly important but particularly challenging reaction. Herein, the metal–organic frameworks MOF-74(Cu) with infinite Cu(II)-O chains and Cu-BTC (BTC=benzene-1,3,5-tricarboxylate) with paddle-wheel binuclear Cu(II) clusters are used as precursors. These MOFs are reduced by NaBH 4 to obtain Cu0/Cuδ+-based photocatalysts denoted as R-MOF-74(Cu) and R-Cu-BTC, respectively. Significantly, R-MOF-74(Cu) achieves a high selectivity of 90.2 % for C 2 H 4 with a yield rate of 6.5 μmol g−1 within 5 h due to its high Cu+ content. To the best of our knowledge, this C 2 H 4 product selectivity is a record high among all the photocatalysts reported so far for photocatalytic CO 2 reduction. In contrast, R-Cu-BTC only forms CO as a product with a cumulative yield of 0.7 μmol g−1 within 5 h. Photoelectrochemical characterization and electron paramagnetic resonance results show that R-MOF-74(Cu) has low interfacial transfer resistance, high photogenerated electron separation efficiency, and excellent CO 2 activation and water oxidation performance. In addition, in situ Fourier transform infrared spectroscopy is used to determine the possible reaction pathway from CO 2 to C 2 H 4 over R-MOF-74(Cu). This work demonstrates the great potential of MOF-derived photocatalysts for the conversion of CO 2 into C 2 H 4 and provides guidance for future photocatalyst development. [ABSTRACT FROM AUTHOR]

With the miniaturization of electronic devices, thermal management has become a critical challenge, especially for high-power systems where efficient heat dissipation is essential. Polycrystalline diamond films, renowned for their exceptional thermal conductivity, offer a promising solution. However, the thermal boundary resistance (TBR) at the diamond/substrate interface remains a significant bottleneck, severely impacting heat dissipation efficiency. This study presents a measurement approach tailored for quantifying TBR in thick-film diamond heterostructures, focusing on diamond-on-silicon (Diamond-on-Si) systems with a silicon nitride barrier layer. Compared to conventional methods, such as transient thermoreflectance techniques, which often exhibit limited sensitivity for thick layers, this approach demonstrates greater reliability and applicability. The findings establish a foundation for advancing strategies to reduce TBR and improve the thermal management performance of diamond films in high-power electronic applications. [ABSTRACT FROM AUTHOR]

Li metal batteries with garnet‐type solid electrolytes have the potential to increase specific energy and power densities of current Li‐ion batteries. Li metal batteries have been hampered by the poor wettability of solid electrolyte with elemental lithium. Here, to resolve the solid garnet electrolyte/Li interface issue, a scalable, cost‐effective, and efficient surfactant‐assisted wet‐chemical strategy is developed. A ZnF2 interlayer coating is applied on Ba and Ta ‐co‐doped Li7La2.75Ba0.25Zr1.75Ta0.25O12 that formed LiF and Li‐Zn alloy upon contact with molten Li. Conformal contact applying a homogenous surfactant‐assisted ZnF2 coating reduced the interfacial resistance from 87 to 15.5 Ω cm2 which enhanced critical current density to a record high value of 5 mA cm−2 at room temperature. Dense and Li2CO3 free garnet solid electrolyte assisted in achieving long‐term stability for 1000 cycles at 1 mA cm−2. Interface stabilized Li/ZnF2‐ solid electrolyte/liquid electrolyte/LiFePO4 cell displayed a 90% capacity retention over 800 cycles at 0.2 C, with Coulombic efficiency of 99% as well as excellent cycle stability at 1 C, with ≈91% of capacity retention for 500 cycles. Using a new design principle for Li anode interfaces, next‐generation power‐intensive and stable solid‐state Li metal batteries can be developed. [ABSTRACT FROM AUTHOR]

The interfacial properties of fiber asphalt aggregate and the cracking resistance of asphalt mixture are directly affected by moisture infiltration. In order to investigate the correlation between interfacial properties and immersion stability of asphalt mixture, three different types of fiber, including basalt fiber (BF), glass fiber (GF), and polyester fiber (PF); five types of fiber contents (0.1% to 0.5% by mass of the mixtures); and two types of aggregates (basalt and limestone) were selected. Experimental methods such as the Bond Strength Test (BBS), Disk-Shaped Compact Tension test (DCT), and interfacial image processing were used in order to assess the strength of interfacial interaction and resistance to cracking under both dry and wet conditions. The results showed that the addition of fibers could enhance fiber asphalt mastic-aggregate interfacial strength; under the influence of moisture infiltration, the interfacial strength showed a significant downward trend. In the process of fiber content increasing from 0.1% to 0.5%, the peak load and fracture energy of fiber asphalt mixtures were first increased and then decreased. The interface between asphalt mastic and aggregate is easier to spalling after being subjected to moisture infiltration, resulting in a decrease in cracking resistance. Compared with the dry environment, after moisture infiltration, the correlation index between interfacial strength and fracture energy is much higher than other influencing factors. The interfacial strength is still an important factor affecting the fracture energy. These findings provide valuable insights for the design and application of more durable asphalt pavement. [ABSTRACT FROM AUTHOR]

• Cu coating synergistically improves thermal and mechanical properties of composite. • Thermal diffusivity of composites is enhanced by 52.97% via introducing Cu coating. • Cu coating can promote Al, Mn, and Ni in Mg matrix to accumulate to the interface. Mg alloy matrix composites reinforced with short carbon fibers (C sf /Mg) are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight, excellent mechanical properties, and heat dissipation. However, the different characteristics of C sf and Mg alloy make the interface a critical issue affecting the synergistic improvement of thermal and mechanical properties of the composites. Here, Cu coating with different thicknesses is introduced to modify the C sf /Mg interface, so as to simultaneously enhance the thermal and mechanical performances, which can combine the advantages of coating modification and matrix alloying. Results reveal that thermal diffusivity (TD) of 3-C sf -Cu/Mg composites is as high as 22.12 mm2/s and an enhancement of 52.97% is achieved compared with C sf /Mg composites, as well as 16.3% enhancement of ultimate compressive strength (UCS) in the longitudinal direction, 8.84% improvement of UCS in the transverse direction, and 53.08% increasement of ultimate tensile strength (UTS). Such improvement can be ascribed to the formation of intermetallic compounds. The formation of intermetallic compounds can not only effectively alleviate the lattice distortion of the matrix and decrease interfacial thermal resistance, but also bear the loads. Our work is of great significance for designing C sf /Mg composites with integrated structure and function. [ABSTRACT FROM AUTHOR]

Current collectors are key components of lithium-ion batteries, providing conductive pathways and maintaining interfacial stability with the electrode materials. Conventional metal-based current collectors, such as aluminum and copper, exhibit excellent conductivity and mechanical strength. However, they have considerable limitations, including electrochemical corrosion, interfacial resistance caused by the formation of passive layers, and mechanical degradation due to repeated cycling. To overcome these challenges, various carbon-based coatings, including amorphous carbon, graphene, and carbon nanotubes, have been developed. These coatings enhance the current collector performance by improving the collector conductivity, chemical stability, and interfacial adhesion. Vertically aligned graphene-like structures known as carbon nanowalls (CNWs) have garnered attention owing to their unique architecture, resulting in high surface area, exceptional conductivity, and excellent thermal and mechanical properties. In this mini-review, the recent advancements in carbon-based coating technologies and their role in enhancing the performance of current collectors were summarized, focusing on the innovative applications of CNWs in next-generation energy storage systems. [ABSTRACT FROM AUTHOR]

Stainless steel (SS) is highly susceptible to corrosion in acidic environments, which significantly limits its applicability in such conditions. In this paper, a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid (PEDOT-PSS)/waterborne acrylic resin (AR) composite coating was designed and prepared for enhancing the corrosion resistance of 304SS. Corrosion current density (jcorr) of the PEDOT-PSS/AR-coated 304SS at the simulated PEMFCs' operating temperature (80 °C) is only 0.86 μA·cm−2 which achieves the 2025 DOE goal (jcorr < 1 μA·cm−2). The improved corrosion resistance would be attributed to both the anode protection and barrier effect provided by the PEDOT-PSS/AR coating. Moreover, the 304SS coated by the PEDOT-PSS/AR obtains a lower interfacial contact resistance (ICR) of 37.01 mΩ·cm2 at 1.4 MPa than that coated by the pure AR coating with the ICR of 167.95 mΩ·cm2. This eco-friendly, conducting, and anti-corrosive PEDOT-PSS/AR coating offers a new insight into high-performance applications for SS. [ABSTRACT FROM AUTHOR]

Controlling the motion of neutral excitons in optically active media is a mandatory development to enable the conception of advanced circuits and devices for applications in excitronics, quantum photonics, and optoelectronics. Recently, proof of unidirectional exciton transport from high‐ to low‐bandgap material is evidenced using a high‐quality lateral heterostructure separating transition metal dichalcogenide monolayers (TMD‐MLs). In this paper, by combining room‐temperature micro‐photoluminescence far‐field imaging with a statistical description of exciton transport, the underlying excitonic local distribution and fluxes taking place near lateral heterojunctions are unveiled. The complex 2D excitonic transport properties found near a linear interface separating WSe2 from MoSe2 TMD‐MLs are studied and reveal two distinct diffusion regimes profoundly affecting the effective diffusion length. Then, it is shown that combining two and three of these interfaces, allows advanced in‐plane control of the excitonic distribution and flux over large distances. Exciton focalization and trapping, allowing an increase in the local exciton density up to three orders of magnitude are demonstrated. Finally, flux collimation is achieved with the formation of parallel current lines extending a few micrometers away from the source. We believe that the deterministic shaping and positioning of the exciton distribution and flux shown here will be key toward the conception of realistic excitronic devices. [ABSTRACT FROM AUTHOR]

Garnet electrolyte Li6.5La3Zr1.5Ta0.5O12 (LLZTO) has been identified as a promising candidate for solid‐state batteries (SSBs). However, the implementation of garnet‐based SSBs is severely restricted owing to the Li dendrite originating from the uneven Li+ deposition and the electron leakage. Herein, one high‐performance garnet‐based SSB is proposed through the enhancement of interfacial dynamics and the inhibition of electron penetration, induced by an artificial harmonized interphase (LSF). The formation of a tightly bonded LLZTO|Li interface is facilitated by the Li3Sb with lower interfacial energies against LLZTO and Li, elucidated by the density functional theory (DFT) calculations. Furthermore, electron leakage and dendrite infiltration are effectively suppressed by the LiF with the electron‐insulating nature and an exceptional γE value. Therefore, a low interfacial resistance of 4.8 Ω cm2 is successfully achieved by the utilization of the functional LSF interphase layer, and the Li|LLZTO‐LSF|Li symmetric cell displayed prolonged Li plating/stripping stability over 1200 h at 0.3 mA cm−2. Moreover, the LFP|LLZTO‐LSF|Li full cell also exhibited notable cycling performance (93.1% capacity retention after 200 cycles at 1 C). The utilization of a synergistic interlayer has been identified as an effective strategy for the advancement of garnet‐based solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

Aqueous potassium‐ion batteries with inherent safety, high abundance, and competitive hydrated ion‐radius point to future availability in energy storage. However, the extensively studied electrodes (metal‐oxides, Prussian‐blue‐analogues, etc.) typically suffer from undesirable capacities and sluggish kinetics owing to overwhelming ion diffusion barriers. Herein, for the first time, the metal chalcogenide bismuth selenide reinforced by iodine‐doping (I‐Bi2Se3) is implemented for high‐performance aqueous potassium‐ion storage. The co‐intercalation mechanism of potassium‐ion with proton in I‐Bi2Se3 is entirely revealed by operando synchrotron X‐ray diffraction and substantial ex‐situ analysis, and the excellent interlayer diffusion kinetics in the high‐conductive host are further enhanced by iodine‐doping, as proposed by theoretic calculations. Therefore, the resulting high diffusion coefficient and low interfacial transfer resistance endow I‐Bi2Se3 with superior rate performance (109.2 mAh g−1 at 10 A g−1) and cycling stability (91% capacity retention after 1200 cycles). Employing in hybrid‐ion batteries matching zinc metal, the highest reversible aqueous potassium‐ion storage to date of 316.8 mAh g−1 is demonstrated, permitting the establishment of reliable performance pouch cells. The promising aqueous potassium intercalation chemistry built in the improved metal chalcogenide is proven to be extendable to other hybrid‐ion devices, offering novel mechanistic insights and material practices for aqueous energy storage. [ABSTRACT FROM AUTHOR]

Garnet‐type Li6.5La3Zr1.5Ta0.5O12 (LLZTO) solid electrolytes provide the necessary electrochemical stability and ionic conductivity for solid‐state lithium‐metal batteries (SSLMBs). However, their wider application is hindered by their high interfacial resistance with electrodes and a lengthy synthesis process. This study presents the synthesis of densified LLZTO electrolytes using unconventional Li2O and Li2ZrO3 precursors through an ultrafast (≈60 s) Joule heat‐assisted synthesis approach in a single‐step process. The lower sintering temperature of Li2ZrO3 compared to traditional ZrO2 precursor yields LLZTO with larger grains, resulting in enhanced Li+ conductivity (7.0 × 10−4 S cm−1 at 25 °C), reduced electronic conductivity (1.7 × 10−10 S cm−1), and higher density (94.2%). Applying a 52–80 nm Sn:SnF2 coating on the LLZTO surface using a melt‐quenching approach produces a uniform interlayer that chemically converts to Li‐Sn alloy and LiF upon contact with lithium, resulting in a near‐zero interfacial resistance and a critical current density of 4.2 mA cm−2 at 25 °C. The SSLMBs, incorporating Sn:SnF2‐coated LLZTO electrolyte with NMC811 cathode, demonstrate remarkable initial capacity (181.1 mAh g−1) and cycle performance (88.63% capacity retention at 3000th cycle). The results indicate that this approach has the potential to advance the commercial fabrication technology for high‐performance solid electrolytes for SSLMBs. [ABSTRACT FROM AUTHOR]

This study presents an experimental measurement of interfacial thermal resistance (ITR) at polymer–polymer interfaces using a multi‐layered bulk sample approach. ITR is commonly measured using thin‐film techniques, but new advancements enable testing in bulk materials with multilayered structures. However, traditional multilayer fabrication is often resource‐intensive and lacks consistency. This study introduces a simple rotational overlapping method for fabricating multi‐layered polymer samples for bulk ITR measurement. Combining numerical simulations with experimental validation, researchers optimize layer overlapping conditions using measured viscosity data of high‐density polyethylene (HDPE), polypropylene (PP), and polylactic acid (PLA). Samples are fabricated at viscosity‐matching temperatures, and shear forces from stirring disks create uniform layer patterns. Computational fluid dynamics (CFD) simulations elucidate the layer formation mechanism, enabling the fabrication of samples with over 112 layers within a 4.6 mm thickness. ITR testing reveals a direct correlation between layer number and thermal resistance. PE‐PP samples exhibit an average ITR of 9.58 × 10−6 K m2 W−1, with a 10.32% increase in resistance from 38 to 112 layers. Similarly, PE‐PLA samples with an ITR of 1.31 × 10−5 K m2 W−1 show a 2.8% increase from 5 to 23 layers. Overall, The experimental procedure provides valuable data to advance the understanding of ITR in polymer–polymer interfaces. [ABSTRACT FROM AUTHOR]

The contact resistances at the metal–organic interface often limit the performance of organic thin-film transistors. However, it is not straightforward to characterize the electrical property of the metal–organic interface of the organic thin film. This is because the conventional electrical measurement only gives the total electrical property of the metal–organic–metal system that is affected by many grain boundaries. In this study, we investigated a single pentacene grain connected to a Au electrode by time-resolved electrostatic force microscopy (tr-EFM), which can capture the time-evolving electrostatic force images at a nanometer-scale spatial resolution. Using the tr-EFM, we found the gradual and uniform potential increase in the pentacene grain following the positive step voltage applied to the Au electrode, which indicates that the resistance in the grain–electrode system is governed by the grain–electrode interfacial resistance. By assuming the equivalent circuit of the grain–electrode interface system, we reconstructed the femto-ampere-order current-to-voltage characteristic at the grain–electrode interface. The asymmetric characteristic in the hole injection regime and the ejection regime suggests the existence of a metal–organic Schottky junction at the interface. [ABSTRACT FROM AUTHOR]

ABSTRACT During the process of treating soft soil foundations with prefabricated drainage drains (PVD), “soil columns” form around the PVD, and a “weak zone” forms outside the range of the “soil columns.” The difference in properties between the two forms a distinct interface, leading to a gradual decrease in drainage efficiency and obstruction of vertical drainage channels, which in turn causes cracks and lateral displacement in the soil during consolidation. The interfaces between adjacent soil layers are incomplete contact, and the water within the interstices impedes the transfer of heat, manifesting a thermal resistance effect. To address this phenomenon, a synchronous measurement system for the thermal gradient and the heat flux density between the soil interfaces has been developed. Applying Fourier's law of heat conduction, the thermal resistance coefficient has been determined. Based on the theory of thermo‐hydro‐mechanical coupling, a multi‐zone axisymmetric model for saturated soils that considers thermal resistance effect has been proposed. Semi‐analytical solutions were derived and validated through comparison with the custom FEM model and field experiments. The thermal consolidation characteristics of the multi‐zone soils under various thermal contact models have also been discussed, with a comprehensive analysis of the influence of different parameters. Outcomes show that: the generalized incomplete thermal contact model provides a better description of the thermal resistance phenomenon between multi‐zone soils interfaces; ignoring the thermal resistance effect leads to an overestimation of the deformation during the thermal consolidation, and, the thermal resistance effect decreases the influence of the thermo‐osmosis effect on the consolidation characteristics. [ABSTRACT FROM AUTHOR]

The performance of solid‐state lithium‐metal batteries (SSLMB) is often constrained by the low ionic conductivity, narrow electrochemical window, and insufficient mechanical strength of polyethylene oxide (PEO)‐based electrolytes. Inspired by the soft‐outside, rigid‐inside structure of starfish, we designed multifunctional “starfish‐type” composite polymer electrolytes (CPEs) using electrospinning technology. These CPEs feature a three‐dimensional rigid skeleton network composed of polyacrylonitrile/metal–organic frameworks/ionic liquids (PAN/MOFs/ILs), creating continuous and efficient Li+ transport channels: MOFs impart rigidity, PEO acts as a cushioning outer layer to enhance interfacial compatibility, and ILs reduce interfacial resistance. The resulting CPEs exhibited excellent ionic conductivity (4.37×10−4 S cm−1), a wide electrochemical window (5.34 V), uniform lithium‐ion flux, and a high transference number (0.69). Leveraging these synergistic advantages, the Li/CPEs/Li symmetric cell demonstrated outstanding dendrite suppression for over 1300 hours, and the LiFePO4/CPEs/Li cell retained 90.1 % capacity after 2100 cycles at 1.0 C, which is the best performance reported for SSLMB with MOF/PEO. The formation of multi‐component solid‐electrolyte interphase and its role in stabilizing lithium metal cycling were systematically elucidated through theoretical simulations and spectroscopic analysis. This nature‐inspired design provides a promising strategy for the development of stable solid‐state electrolytes with extended lifespans. [ABSTRACT FROM AUTHOR]

Titanium (Ti), commercially used as substrate for porous transport layers (PTLs) in proton exchange membrane water electrolyzers (PEMWEs), tends to form passivating oxide layer, increasing interfacial contact resistance (ICR) and reducing performance and durability; practice of using precious metal coatings for mitigation significantly increases costs. This study investigates niobium-tantalum (Nb–Ta) alloys as cost-effective interlayer coatings on Ti-felt to reduce precious metal loading. Nb–Ta coated samples significantly increase corrosion potential, lower current densities by 3–4 orders of magnitude, reduce ICR by 3.5 times, and improve durability. The best performance sample with an ultra-low amount of platinum, shows 8 times greater durability, 12.5% reduction in ohmic resistance and 28% increase in current density at +2.0 V than the commercial PTL in a single cell stack. Improved contact angle, electrical, and thermal conductivity highlight Nb–Ta interlayer coatings for PTLs, offering a cost-effective strategy to enhance PEMWE performance and durability for green hydrogen production. [Display omitted] • Nb–Ta alloy-coated Ti-felt improved corrosion potential, reduced corrosion current. • Nb–Ta alloy-coated Ti-felt lowered interfacial resistance, enhanced durability. • Pt layer on alloy interlayer increased durability eightfold over commercial samples. • Pt/Nb–Ta alloy reduced ohmic resistance by 12.5%, increased current density by 28%. • Pt/Nb–Ta alloy sample enhanced corrosion resistance, durability, and conductivity. [ABSTRACT FROM AUTHOR]

Fuel cell systems are potential power sources for transportation applications due to their high energy efficiency, rapid start-up, and low emissions. The bipolar plates, which constitute the major volume of the fuel cell stack, are usually made of graphite. However, the brittle nature of graphite plates makes them unable to resist shock or vibration; as a result, metallic plates are considered as bipolar plates in fuel cell stacks due to their resistance to impact, strength, and cost-effective manufacturing. However, surface corrosion and hydrophobicity are significant challenges that need to be overcome in the fuel cell working environment. In this study, the resistance of SS304 plates to the electrochemical environment is enhanced by coating them with TiN, while the hydrophobic surface of the stainless steel is induced using femtosecond lasers and vacuum treatments. The effects of treatment conditions on surface morphology, contact angle, interfacial resistance, and fuel cell performance are investigated. Results show that linearly polarized lasers with scanning speeds of 20 mm s−1 and 80 mm s−1 are the optimum treatments for SS304 and TiN-coated SS304 plates, respectively. The TiN coating greatly improves the performance of SS304 flow field plates, with a maximum power density of 0.9 W cm−2 compared to 0.44 W cm−2 without the coating. Fuel cells consisting of laser-processed TiN-coated SS304 flow field plates can also operate durably with hydrogen and oxygen at the anode and cathode, respectively. [Display omitted] • Superhydrophobic surface of SS304 plates is created by femtosecond laser treatment. • A scanning speed of 80 mm s−1 is suitable for 3–5 μm thin TiN-coated SS304. • Four hours of vacuum-treated laser-processed SS304 exhibits a contact angle of 152.6°. • Fuel cell exhibits a high stability with maximum power density of 0.9 W cm−2. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) are efficient, environmentally friendly devices for applications such as transportation and stationary power generation. The bipolar plate (BP) is a key component in PEMFCs, responsible for electrical conductivity, gas distribution, and water management. 6061 aluminum alloy (AA) is commonly used for BPs due to its lightweight and conductive properties, but it is prone to corrosion. This study examines the efficacy of polypyrrole (PPy) coatings that are enhanced with chromium nitride (CrN) nanoparticles (NPs) on 6061 AA specimens. These coatings greatly enhance the corrosion resistance, polarization resistance, and protection efficiency of the 6061 AA. Out of all the coatings that were tested, the PPy-CrN0.2 coating stood out as the top performer. It showed a positive corrosion potential (Ecorr) of − 0.51 V versus SCE and a significantly lower corrosion current (Icorr) of 0.44 µA/cm2. This coating demonstrates the highest polarization resistance value of 47,904.53 Ω/cm2 and achieves an impressive protection efficiency of 72.84%, surpassing other coated specimens. In addition, the PPy-CrN0.2 coating demonstrates exceptional protective properties, boasting an impressive impedance value (Z) of 5019 Ω/cm2. This underscores its remarkable effectiveness in preventing the infiltration of corrosive ions, as confirmed by electrochemical impedance spectroscopy. Future characterization studies, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) will further elucidate the structural and functional properties of the PPy-CrN0.2 coating. Additionally, interfacial contact resistance (ICR) measurements were conducted to assess the electrical performance of the coating. The PPy-CrN0.2 coating demonstrated the lowest ICR value of 18.4 mΩ/cm2 at a compaction pressure of 1.4 MPa, confirming its improved conductivity and suitability for PEMFC applications. These findings highlight the importance of ICR testing in evaluating the overall performance and efficiency of the PPy-CrN0.2 coating in PEMFC systems. [ABSTRACT FROM AUTHOR]

Surface coating lithium‐ion battery cathodes is a promising strategy to improve performance and mitigate cathode degradation. The coatings studied to date focus on either electronically or ionically conducting layers, which have been introduced to enhance the redox reactions of cathode particles, or oxide‐based physical protection layers limiting surface degradation. Such coatings require high‐temperature, time‐consuming synthesis processes, along with uncertainty in the specific interactions between these coatings and lithium ions. Here, metal‐phenolic network coated LiNi0.6Mn0.2Co0.2O2 (NMC) cathodes are, produced using naturally occurring polyphenols via a rapid one‐step assembly, improve cathode electrochemical performance. The performance improvement arises from the interaction between lithium ions and the coated layer, which enhances the lithium‐ion transport to the cathode. In half‐cell 1C rate cycling conditions, the modified cathode displays a 20% reduction in overpotential and a 54% decrease in interfacial resistance compared to the uncoated cathode. In a full‐cell format, the modified cathode exhibits a 10% increase in capacity and a 54% increase in lifespan for constant current cycling; in addition to a 5% increase in capacity and a 25% increase in lifespan for constant current‐constant voltage (CCCV) cycling. This work paves the way for improving cathode materials via eco‐friendly lithium‐ion attraction strategies. [ABSTRACT FROM AUTHOR]