Controllable and scalable preparation of electrocatalyst materials holds significant importance for their practical *** sputtering is a highly effective synthesis method,known for its producing uniform films and allow...
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Controllable and scalable preparation of electrocatalyst materials holds significant importance for their practical *** sputtering is a highly effective synthesis method,known for its producing uniform films and allowing easy control of component *** this paper,we propose an in-situ synthesis method for layered double hydroxide(LDH)electrocatalysts through sacrificing magnetron sputtered *** resulting FeCo-LDH catalyst demonstrated a low overpotential of only 300 mV at 10 mA·cm^(-2).Furthermore,we conducted spectroscopic analysis to investigate the surface changes of the catalysts during the oxygen evolution reaction(OER)*** findings indicated that the formation of Co oxyhydroxides plays a beneficial role in enhancing the catalytical performance of the FeCo-LDH for OER *** restructuring strategy of converting a magnetron-sputtered sacrificial film into a catalytical LDH introduces a new avenue to the synthesis of transition metal-based electrocatalysts.
The safety and cycle lifespan of zinc metal-based aqueous batteries are greatly restricted by zinc *** poor cycling performance of zinc metal anode is often considered to be impacted by the dendrite growth,surface pas...
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The safety and cycle lifespan of zinc metal-based aqueous batteries are greatly restricted by zinc *** poor cycling performance of zinc metal anode is often considered to be impacted by the dendrite growth,surface passivation,zinc metal corrosion and hydrogen evolution reaction,while surface roughness is a matter that has often been ignored in past ***,a roughness gradient is constructed on the zinc anode surface by a simple grinding and pasting *** has been found the modified zinc anodes with lower surface roughness exhibit the smaller zinc deposition overpotential and longer cycle ***,in situ optical microscopy photographs indicate that the zinc anode with an optimized roughness enables more uniform distribution of zinc precipitation and corrosion sites,which will facilitate a stable cycling performance of aqueous zinc ion *** Zn anode dendrite-suppressing mechanism via surface roughness engineering was revealed through finite element computational *** results emphasize the effectiveness of roughness engineering for tuning the surface physics of Zn anode and provide a facile strategy to develop better and safer aqueous zinc ion batteries.
Thermoelectric superlattices are expected to decouple the strong correlation between various thermo-electric parameters,and are an important strategy for excellent thermoelectric *** superlattices of(Bi_(2))m(Bi_(2)Te...
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Thermoelectric superlattices are expected to decouple the strong correlation between various thermo-electric parameters,and are an important strategy for excellent thermoelectric *** superlattices of(Bi_(2))m(Bi_(2)Te_(3))n homologous series are well-known for low lattice thermal conductivity and intriguing topological surface ***,the impacts of electronic structure on the thermo-electric performance were still not well-understood in(Bi_(2))m(Bi_(2)Te_(3))*** cope with this issue,Bi_(2)eBi_(2)Te_(3)superlattice-like films with adjustable Bi_(2)/(Bi_(2)+Bi_(2)Te_(3))molar ratio(R)were successfully fabricated by the molecular beam epitaxy ***-resolved photoemission spectroscopy measurements com-bined with theoretical calculations revealed the conduction band evolution from single-valley to multi-valley as R≥0.30,leading to intrinsically high carrier effective mass and improved thermoelectric power ***,the superlattice film(R=0.46)with the structure close to Bi_(4)Te_(3)possesses the topological surface state feature around the high symmetry *** a result of the high effective mass of 3.9 m0 and very high electron density of_(2).31×10^(21)cm^(-3),the film with R=0.46 acquired the highest power factor of 1.49 mW·m^(-1)·K^(-2)at 420 K,outperforming that of other(Bi_(2))m(Bi_(2)Te_(3))n *** work lays an essential foundation on understanding the electronic structure and further improving thermoelectric performances of(Bi_(2))m(Bi_(2)Te_(3))n homologous series.
The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was p...
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The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.
Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active *** work propos...
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Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active *** work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic *** employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging ***,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky *** from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1) at 0.2 A g^(−1) under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 *** results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.
High-voltage LiCoO_(2) (LCO) can deliver a high capacity and therefore significantly boost the energy density of Li-ion batteries (LIBs). However, its cyclability is still a major problem in terms of commercial applic...
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High-voltage LiCoO_(2) (LCO) can deliver a high capacity and therefore significantly boost the energy density of Li-ion batteries (LIBs). However, its cyclability is still a major problem in terms of commercial applications. Herein, we propose a simple but effective method to greatly improve the high-voltage cyclability of an LCO cathode by constructing a surface LiF modification layer via pyrolysis of the lithiated polyvinylidene fluoride (Li-PVDF) coating under air atmosphere. Benefitting from the good film-forming and strong adhesion ability of Li-PVDF, the thus-obtained LiF layer is uniform, dense, and conformal;therefore, it is capable of acting as a barrier layer to effectively protect the LCO surface from direct exposure to the electrolyte, thus suppressing the interfacial side reactions and surface structure deterioration. Consequently, the high-voltage stability of the LCO electrode is significantly enhanced. Under a high charge cutoff voltage of 4.6 V, the LiF-modified LCO (LiF@LCO) cathode demonstrates a high capacity of 201 mA h g^(−1) at 0.1 C and a stable cycling performance at 0.5 C with 80.5% capacity retention after 700 cycles, outperforming the vast majority of high-voltage LCO cathodes reported so far.
Poly(vinylidene fluoride)(PVDF)is the most attractive piezoelectric polymer for application in flexible *** attain excellent piezoelectric properties,a substantial amount of spontaneous polarβ-phase content is highly...
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Poly(vinylidene fluoride)(PVDF)is the most attractive piezoelectric polymer for application in flexible *** attain excellent piezoelectric properties,a substantial amount of spontaneous polarβ-phase content is highly ***,the current reported manufacturing methods to increaseβ-phase contents are inconvenient and complex,hindering progress in PVDF's *** work proposes a folding-hot-pressing method to fabricate highβ-phase-content PVDF *** characterization indicates that the films haveαandβphases and the folding-hot-pressing process transforms theαphase into theβ*** to the 97.5%β-phase content and aligned structure,a piezoelectric constant of 20 pC/N is achieved in the three-times folded ***,the process method enhances the tensile strength(126.2 MPa)of the films,with a low Young's modulus(0.87 GPa)remaining,making the films applicable for flexible piezoelectric ***,sensors based on the achieved films were assembled and applied for human physiological activity *** work offers a scalable new melt-processing strategy for developing high-performance PVDF-based piezo-electric composite films for wearable electronic devices.
Magnetic skyrmions are particle-like topological magnetic textures that are potential information carriers in future *** enormous body of research confirms their existence in a broad range of magnetic materials since ...
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Magnetic skyrmions are particle-like topological magnetic textures that are potential information carriers in future *** enormous body of research confirms their existence in a broad range of magnetic materials since their first discovery in *** date,magnetic skyrmions can not only be found in asymmetric systems but also in centrosymmetric ***,engineered magnetic multilayers are promising structures for skyrmion-based spintronics because they can stabilize small-sized skyrmions at room temperature and facilitate their electric *** this overview,we introduce the topological nature,their special properties,and nucleation methods of skyrmions,and show their potential for *** on skyrmionic devices and developments toward other,more three-dimensional particle-like magnetic nanostructures,are discussed at the end.
Two-dimensional(2D) van der Waals(vdW) heterostructures have emerged as a groundbreaking candidate for future integrated circuits due to their tunable band structures,atomically sharp interfaces and seamless compa...
Two-dimensional(2D) van der Waals(vdW) heterostructures have emerged as a groundbreaking candidate for future integrated circuits due to their tunable band structures,atomically sharp interfaces and seamless compatibility with complementary metal-oxide-semiconductor *** their promise,existing synthesis methods,such as mechanical transfer and vapor-phase conversion,struggle to achieve the high-quality,scalable production for practical *** response to these longstanding challenges,our study unveils for the first time the direct epitaxial growth of wafer-scale 2D vdW heterostructures(MoS2/SnS2) with exceptional quality and *** achievement is made possible through fundamentally enhancing the adsorption interactions between intermediates and the underlying *** heterostructures display pristine,defect-free interfaces,consistent crystal orientation and wafer-level thickness *** Raman peak shifts of MoS2and SnS2are constrained to below 0.5 cm-1across the entire wafer,with intensity deviations maintained within an impressive 2%,and thickness uniformity surpassing 99.5%.Owing to their exceptional crystallinity and interface quality,the heterostructures demonstrate extraordinary electron and hole transfer capabilities,showcasing a prominent rectification effect and an astounding responsivity of 6.28 ± 10~3 A/W,averaged from 30 *** study signifies a pivotal advancement for the integration of 2D materials into semiconductor technologies,paving the way for next-generation integrated circuits.
Smart wearable market is burgeoning,and flexible energy storage is crucial to cope with its *** commonly-used metal-based current collectors are heavy with limited *** carbon-based current collectors are expensive and...
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Smart wearable market is burgeoning,and flexible energy storage is crucial to cope with its *** commonly-used metal-based current collectors are heavy with limited *** carbon-based current collectors are expensive and ***,the poor interface between active material and current collector leads to unsatisfactory ***,these two issues are attempted to be solved by using cheap and lightweight polyester-based fabrics as well as in-situ growth.A deposited thin layer of nickel on the fabrics not only enhances the conductivity,but also serves as the sacrificial precursor for the growth of active ***,intimate contact is secured via chemical *** electrode with ternary(metalinorganic-organic)component shows excellent electrochemical ***,high areal capacity is realized(2.2 C cm^(-2)at 2 mA cm^(-2)),which is far superior to its rigid nickel-foam-based ***,an allsolid-state supercapacitor device was *** device provides an areal capacity of 2.03 C cm^(-2)at the current density of 2 mA cm^(-2).It realizes an energy density of 0.45 mWh cm^(-2)when the power density is 1.6 mW cm^(-2).This work offers a feasible and cost-efficient way for fabricating electrode materials with excellent performance for portable supercapacitors.
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