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All‐solid‐state Li metal batteries (ASSLMBs) using inorganic solid‐state electrolytes (ISEs) are considered promising energy storage technologies owing to their intrinsic safety and high energy density. Nevertheless, one critical challenge confronting ASSLMBs is the inability of the ISEs to prevent Li dendrite growth, which has not yet been fully addressed. Herein, general design principles of artificial solid electrolyte interphases (ASEI) for suppressing Li dendrites in ASSLMBs are proposed by systematically exploring the formation mechanism of Li dendrites. Subsequently, a tailored LiF‐Li3N ASEI is constructed to inspect the Li‐dendrite‐free design principles. The LiF‐Li3N modified Li (LFN‐Li) can effectively inhibit the side reactions and suppress the growth of Li dendrites, thus boosting the critical current densities of Li10GeP2S12 (LGPS) to a record‐high value of 3.4 mA cm−2. Furthermore, the LFN‐Li/LGPS/LFN‐Li can cycle stably for over 5000 h at 0.2 mA cm−2. Crucially, the versatility of the designed ASEI is highlighted as it ensures outstanding long‐term stability in symmetric cells featuring oxide Li1.3Al0.3Ti1.7(PO)3 or halide Li2ZrCl6 ISEs. As a result, the ASEI enables LiNi0.8Mn0.1Co0.1O2/LGPS/LFN‐Li and FeS2/LGPS/LFN‐Li cells to achieve high discharge‐specific capacities and desirable cyclic stability at room temperature. The generalized ASEI design principles rationalize the development of high‐energy ASSLBMs. [ABSTRACT FROM AUTHOR]

BiCuSeO is a promising oxygen‐containing thermoelectric material due to its intrinsically low lattice thermal conductivity and excellent service stability. However, the low electrical conductivity limits its thermoelectric performance. Aliovalent element doping can significantly improve their carrier concentration, but it may also impact carrier mobility and thermal transport properties. Considering the influence of graphene on carrier‐phonon decoupling, Bi0.88Pb0.06Ca0.06CuSeO (BPCCSO)‐graphene composites are designed. For further practical application, a rapid preparation method is employed, taking less than 1 h, which combines self‐propagating high‐temperature synthesis with spark plasma sintering. The incorporation of graphene simultaneously optimizes the electrical properties and thermal conductivity, yielding a high ratio of weighted mobility to lattice thermal conductivity (144 at 300 K and 95 at 923 K). Ultimately, BPCCSO‐graphene composites achieve exceptional thermoelectric performance with a ZT value of 1.6 at 923 K, bringing a ≈40% improvement over BPCCSO without graphene. This work further promotes the practical application of BiCuSeO‐based materials and this facile and effective strategy can also be extended to other thermoelectric systems. [ABSTRACT FROM AUTHOR]

All‐solid Na‐ion batteries (ASNIBs) present significant potential for integration into large‐scale energy storage systems, capitalizing on their abundant raw materials, exemplary safety, and high energy density. Among the pivotal components propelling the advancement of ASNIBs, inorganic solid electrolytes (ISEs) have garnered substantial attention in recent years due to their high ionic conductivity (σ), wide electrochemical stability window (ESW), and high shear modulus. Herein, this review systematically encapsulates the latest strides in Na‐ion ISEs, furnishing a comprehensive panorama of various ISE systems along with their interface engineering strategies against the electrodes. The prime focus resides in accentuating key strategies for refining ion conduction properties and interfacial compatibility of ISEs through structure design and interface modification. Furthermore, the review explores the foremost challenges and prospects inherent to sodium‐ion ISEs, striving to deepen our understanding of how to engineer more robust and efficient ISEs and interface stability, poised for the forthcoming era of advanced ASNIBs. [ABSTRACT FROM AUTHOR]

Lithium argyrodite solid electrolytes have attracted ever‐increasing attention for all‐solid‐state batteries due to their high ionic conductivity and low cost. However, the relation between structure and ionic transport for the halogen‐rich lithium argyrodites under different synthesis routes is still elusive. Herein, the influence of synthesis procedures, such as annealing conditions and balling milling, on the structure, ionic conductivity, and activation energy of the lithium argyrodite (e.g., Li5.5PS4.5Cl1.5, Li5.3PS4.3Cl1.7), is systematically investigated. Compared with high‐energy ball milling followed by annealing, using fast dry mixing followed by annealing can obtain comparable ionic conductivity of the chlorine‐rich lithium argyrodites. Single‐crystal LiNi0.83Co0.11Mn0.06O2‐based solid‐state battery with these electrolytes shows stable cycling performance, demonstrating that chlorine‐rich lithium argyrodite is a promising candidate for all‐solid‐state batteries. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSLBs) are considered a promising technology for next‐generation energy storage systems due to their inherent safety. However, the conventional laboratory‐scale ASSLBs reported to date are based on pellet‐type structures with thick solid electrolyte layers, leading to challenges related to low energy densities and poor electrochemical performance. In this study, porous adhesive poly(ethylene vinyl acetate) (PEVA) scaffolds and polytetrafluoroethylene (PTFE) binders are utilized to interweave sulfide solid electrolytes into freestanding films with an ultra‐low thickness of 40 µm, high ionic conductivity of 1.1 mS cm−1, and a high tensile strength of 74 MPa. To mitigate the reduction reaction between the PTFE binder and the lithium metal anode, a Li3N‐rich solid electrolyte interphase (SEI) in situ on lithium metal is formed, and the assembled symmetric cell shows excellent cycling stability within 800 h at the current density of 0.2 mA cm−2 and room temperature. Additionally, the ASSLBs using oxidatively stable Li2ZrCl5F in the composite cathode and the prepared solid electrolyte film demonstrate exceptional cycling performance and fast‐charging capability, with a high cell‐level energy density of 354.4 Wh kg−1. The ASSLBs prepared by coupling E‐LPSCl film and stable interface design exhibit excellent electrochemical performance and a high cell‐level energy density. [ABSTRACT FROM AUTHOR]

The simultaneous detection of multiple stimuli, such as pressure and temperature, has long been a persistent challenge for developing electronic skin (e‐skin) to emulate the functionality of human skin. Meanwhile, the demand for integrated power supply units is an additional pressing concern to achieve its lightweightness and flexibility. Herein, we propose a self‐powered dual temperature–pressure (SPDM) sensor, which utilizes a compressible ionic gel electrolyte driven by the potential difference between MXene and Al electrodes. The SPDM sensor exhibits a rapid and timely response to changes in pressure‐induced deformation, while exhibiting a slow and hysteretic response to temperature variations. These distinct response characteristics enable the differentiation of current signals generated by different stimuli through machine learning, resulting in an impressive accuracy rate of 99.1%. Furthermore, the developed SPDM sensor exhibits a wide pressure detection range of 0–800 kPa and a broad temperature detection range of 5–75°C, encompassing the environmental conditions encountered in daily human life. The dual‐mode coupled strategy by machine learning provides an effective approach for temperature and pressure detection and discrimination, showcasing its potential applications in wearable electronics, intelligent robots, human–machine interactions, and so on. [ABSTRACT FROM AUTHOR]

NaNbO3‐based antiferroelectric ceramics are promising candidates for high‐performance energy storage capacitors due to their environmental friendliness and low cost despite their current energy storage properties being inferior to those of their lead‐based and AgNbO3‐based counterparts. Typically, the antiferroelectric phase in NaNbO3 ceramics is not stable and the characteristic double hysteresis loops are seldom observed. In this work, the antiferroelectricity was improved by reducing the polarizability, resulting in well‐developed double hysteresis loops in 0.94NaNbO3–0.06(K0.5Bi0.5)SnO3 ceramics. To further improve the energy storage properties, defect engineering was performed for 0.94NaNbO3–0.06(K0.5Bi0.5)SnO3 by substituting Na+ with La3+ and introducing Nb vacancies. As a result, the stability of the field‐induced ferroelectric phase was reduced, and the energy storage properties were enhanced. The strategy of combining polarizability design and defect engineering can be a promising approach for optimizing NaNbO3‐based antiferroelectric ceramics. [ABSTRACT FROM AUTHOR]

With the development of information processing, various neuromorphic synaptic devices have been proposed, including novel devices mimicking multiple sensory systems in the biosome, in which vision is a vital source of information. Due to the pressing issue of high energy consumption and the ever‐increasing complexity of practical application scenarios, there is an urgent need to investigate optoelectronic synapses with simple structure but multifunctional capabilities, thereby broadening their application scope. Here, remarkable performances in both electrical and optical operation modes are achieved in multilayer graphene/CuInP2S6/Au electronic/optoelectronic device. By modulating the electrical and optical pulses, both short‐term and long‐term memory can be emulated in the same device, while visual perception, processing, and memorizing functions are demonstrated in this single cell with relatively low energy consumption. In addition, light adaptive behavior can also be simulated through optical–electrical cooperative modulation in the device, further providing a novel and promising strategy for future applications in artificial visual systems. [ABSTRACT FROM AUTHOR]

Superionic solid electrolytes (SEs) are essential for bulk‐type solid‐state battery (SSB) applications. Multicomponent SEs are recently attracting attention for their favorable charge‐transport properties, however a thorough understanding of how configurational entropy (ΔSconf) affects ionic conductivity is lacking. Here, we successfully synthesized a series of halogen‐rich lithium argyrodites with the general formula Li5.5PS4.5ClxBr1.5‐x (0≤x≤1.5). Using neutron powder diffraction and 31P magic‐angle spinning nuclear magnetic resonance spectroscopy, the S2−/Cl−/Br− occupancy on the anion sublattice was quantitatively analyzed. We show that disorder positively affects Li‐ion dynamics, leading to a room‐temperature ionic conductivity of 22.7 mS cm−1 (9.6 mS cm−1 in cold‐pressed state) for Li5.5PS4.5Cl0.8Br0.7 (ΔSconf=1.98R). To the best of our knowledge, this is the first experimental evidence that configurational entropy of the anion sublattice correlates with ion mobility. Our results indicate the possibility of improving ionic conductivity in ceramic ion conductors by tailoring the degree of compositional complexity. Moreover, the Li5.5PS4.5Cl0.8Br0.7 SE allowed for stable cycling of single‐crystal LiNi0.9Co0.06Mn0.04O2 (s‐NCM90) composite cathodes in SSB cells, emphasizing that dual‐substituted lithium argyrodites hold great promise in enabling high‐performance electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Thermoelectric oxide thin films are promising in chip cooling. The issues on the orientation of thin films are essential as they are related to the structures, morphologies, and thermoelectric properties. In this regard, the orientation modulation is conducted on La‐doped SrTiO3 thin films on (LaAlO3)0.3(Sr2TaAlO6)0.7 (LSAT) single crystal substrates. Layer‐by‐layer growth mode is found in (001)‐ and (110)‐ oriented thin films, resulting in few grain boundaries (GBs). In (111)‐oriented films, island growth mode leads to columnar grain boundaries that build up potential barriers for electrons to be strongly scattered and filtered, suppressing electron mobility and increasing effective mass. In addition, the GBs serve as oxygen vacancy diffusion paths when annealing, causing increased carrier concentration and lattice contraction. The weighted mobility of 71.9 cm2 V−1 s−1 and electrical conductivity of ≈600 S cm−1 are realized in the (001)‐oriented film at room temperature. Ultimately, outstanding power factor values of ≈569 µW m−1 K−2 (room temperature) and ≈791 µW m−1 K−2 (573 K) are successfully achieved, outperforming those in polycrystalline ceramics and (111)‐oriented films. This study systematically investigates the influence of grain boundaries and orientations on SrTiO3‐based thermoelectric films, which lays a solid foundation for improving thermoelectric performance in other oxide thin films. [ABSTRACT FROM AUTHOR]

Mechanically driven polarization switching via scanning probe microscopy provides a valuable voltage‐free strategy for designing ferroelectric nanodomain structures. However, it is still challenging to realize reversible polarization switching with mechanical forces. Here, the mechanically driven reversible polarization switching observed in imprinted ferroelectric BiFeO3 thin films is reported, i.e., up‐to‐down switching by a sharp scanning tip and down‐to‐up switching by a blunt tip. Free energy calculations, phase‐field simulations, and piezoresponse force microscopy reveal that reversible mechanical switching arises from the interplay among the flexoelectric effect, the piezoelectric effect, and the internal upward built‐in field in BiFeO3 films. This study gains a deeper insight into the mechanism and control of mechanically driven polarization switching, and provides guidance for exploring potential ferroelectric‐based electro‐mechanical microelectronics. [ABSTRACT FROM AUTHOR]

Dielectric film capacitors with high power density and rapid charge–discharge capability are widely used as key components in modern electronic and electrical systems, and polymers are primary dielectric for film capacitors due to their low cost, flexibility, and ease of processing. Here, a surface engineering approach is reported to improve the energy storage properties of polymer films by directly spray coating 2D nanosheets on the polymer film surface. The spraying of 2D calcium niobate nanosheets on the surface of biaxially oriented polypropylene (BOPP) films leads to remarkably increased breakdown strength and dielectric constant, resulting in a maximum 64% enhancement of energy density compared to the pristine BOPP films. Ultraviolet irradiation is further employed to improve the adhesion of nanosheets to the BOPP film surface, leading to an ultrahigh energy density of 11.6 J cm−3 with a high energy efficiency of 90%, which is the highest energy density ever achieved in polypropylene‐based films. This work provides a universal, cost‐effective, and scalable approach to improve the energy density of dielectric polymer films, which is of great significance for the application of high‐energy‐density polymer films in compact and efficient power systems. [ABSTRACT FROM AUTHOR]

The magnetoelectric effect is technologically appealing because of its ability to manipulate magnetism using an electric field rather than magnetic field or current, thus providing a promising solution for the development of energy‐efficient spintronics. Although 180° magnetization switching is vital to spintronic devices, the achievement of 180° magnetization switching via magnetoelectric coupling is still a fundamental challenge. Herein, voltage‐driven full resistance switching of a magnetic tunnel junction (MTJ) with dipole interaction on a ferroelectric substrate through switchable parallel/antiparallel magnetization alignment is demonstrated. Parallel magnetization alignment along the y direction is obtained under a bias magnetic field. By rotating the magnetic easy axis via strain‐mediated magnetoelectric coupling, the parallel magnetizations in the MTJ reorient to the x axis with opposite paths because of dipole interaction, thus resulting in antiparallel alignment. Moreover, this voltage switching of MTJs is nonvolatile owing to variations in dipole interaction and can be well understood via phase field simulations. The results provide an avenue to realize electrical switching of MTJs and are significant for exploring energy‐efficient spintronic devices. [ABSTRACT FROM AUTHOR]

Understanding the electromechanical breakdown mechanisms of polycrystalline ceramics is critical to texture engineering for high‐energy‐density dielectric ceramics. Here, an electromechanical breakdown model is developed to fundamentally understand the electrostrictive effect on the breakdown behavior of textured ceramics. Taking the Na0.5Bi0.5TiO3‐Sr0.7Bi0.2TiO3 ceramic as an example, it is found that the breakdown process significantly depends on the local electric/strain energy distributions in polycrystalline ceramics, and reasonable texture design could greatly alleviate electromechanical breakdown. Then, high‐throughput simulations are performed to establish the mapping relationship between the breakdown strength and different intrinsic/extrinsic variables. Finally, machine learning is conducted on the database from the high‐throughput simulations to obtain the mathematical expression for semi‐quantitatively predicting the breakdown strength, based on which some basic principles of texture design are proposed. The present work provides a computational understanding of the electromechanical breakdown behavior in textured ceramics and is expected to stimulate more theoretical and experimental efforts in designing textured ceramics with reliable electromechanical performances. [ABSTRACT FROM AUTHOR]

Layered oxychalcogenides have received extensive attention in the fields of magnetism, superconductivity, lithium battery, and luminescence due to their unique electronic, magnetic properties, and layered structure, among which layered oxyselenides have excellent and promising thermoelectric performance, such as BiCuSeO and Bi2LnO4Cu2Se2. Here, we successfully synthesized Sr2MO2Cu2Se2 (M = Co, Ni, Zn) and Sr2FeO3CuSe and investigated the thermoelectric properties at a wide temperature range (298–923 K). They have a relatively high Seebeck coefficient (>300 μV K−1) in medium to high temperature range and possess a low thermal conductivity. The power factor and ZT reach 65 μW m−1 K−1 and 0.07 at 923 K for intrinsic Sr2NiO2Cu2Se2, and a higher performance is expected to be achieved by strategies like carrier concentration optimization and band structure engineering. [ABSTRACT FROM AUTHOR]

As a transparent thermoelectric oxide, gallium‐doped zinc oxide (GZO) has the potential to power wearable or portable electronics and may be used in the integrated circuits industry for chip cooling. Constructing ZnO–GZO interfaces has been proposed as an effective strategy for improving thermoelectric performance of GZO thin films. However, without the aid of band structure calculation for multilayered films, it is hard to directly elucidate the underlying mechanisms of carrier transport. Weighted mobility is an indicator that reveals the inherent electronic transport properties like carrier scattering, electronic band structure, and so on. Thus, to further investigate the effects of ZnO–GZO interfaces on electrical properties of GZO thin films, the structures containing different numbers of ZnO–GZO interfaces were designed and the correlations among numbers of ZnO–GZO interfaces, weighted mobility, and electrical properties were explored. It was found that with more ZnO–GZO interfaces, the weighted mobility increased, and the power factor values also improved as well. Consequently, an enhanced power factor value reached 439 μW m−1 K−2 at 623 K. This work demonstrated the beneficial effects of multiple interfaces on the improvements of electrical transport performance through analyzing weighted mobility, which laid a foundation for further optimization of thermoelectric performance. [ABSTRACT FROM AUTHOR]

Polymer composite dielectrics capable of high energy density, high efficiency, and high‐temperature stability are in high demand for application in various electronic vehicles and power systems. A major challenge, however, is the reasonable design of high‐performance nanofillers that are beneficial to the polarization and breakdown strength simultaneously. Here, high‐entropy‐induced ceramic nanofibers with a stable Bi2Ti2O7‐type pyrochlore phase are developed as effective nanofillers to enhance the energy storage performance of polyetherimide (PEI) composites. Benefiting from the linear pyrochlore phase, refined grain size, and increased amorphous fraction of the high‐entropy nanofillers, the resultant PEI composites exhibit significantly improved energy storage performance over a wide temperature range of 25–150 °C. Notably, a high energy density of 6.46 J cm−3 under an electric field of 590 MV m−1 is achieved at 150 °C, which outperforms most of the reported PEI composites. This study provides a guideline for the development of dielectric fillers with tunable dielectric properties and microstructures, thus promoting the development of high‐performance polymer composites. [ABSTRACT FROM AUTHOR]

The anomalous Hall effect (AHE) is a quantum coherent transport phenomenon that conventionally vanishes at elevated temperatures because ofthermal dephasing. Therefore, it is puzzling that the AHE can survive in heavy metal (HM)/antiferromagnetic (AFM) insulator (AFMI) heterostructures at high temperatures yet disappears at low temperatures. In this paper, an unconventional high-temperature AHE in HM/AFMI is observed only around the Néel temperature of AFM, with large anomalous Hall resistivity up to 40 nQ cm is reported. This mechanism is attributed to the emergence of a noncollinear AFM spin texture with a non-zero net topological charge. Atomistic spin dynamics simulation shows that such a unique spin texture can be stabilized by the subtle interplay among the collinear AFM exchange coupling, interfacial Dyzaloshinski-Moriya interaction, thermal fluctuation, and bias magnetic field. [ABSTRACT FROM AUTHOR]

With the increasing popularity of smart wearable devices, flexible pressure sensors are highly desired in various complex application scenarios. A great challenge for existing flexible pressure sensors is to maintain high sensitivity over a wide temperature range, which is critical for their applications in harsh environments. Herein, a flexible piezoresistive sensor made of polyetherimide (PEI) fibrous network evenly covered with MXene nanosheets is reported to construct conductive pathways, showing ultrahigh sensitivity over a wide temperature range from −5 °C (sensitivity of 80 kPa−1) to 150 °C (20 kPa−1), low detection limit of 9 Pa, fast response time of 163 ms, outstanding durability over 10 000 cycles at room temperature, 2000 cycles at 100 °C and 500 cycles at −5 °C. The pressure sensor can monitor various human activities in real‐time, apply to human–machine interaction, and measure pressure distribution. It also can sensitively respond to external mechanical stimuli at 150 °C and extremely low temperature (in liquid nitrogen). Moreover, the fibrous network exhibits an excellent Joule heating performance, which can reach 78 °C at an applied voltage of 12 V. Thus, the piezoresistive sensor has considerable potential for wearable garments and personal heating applications in harsh temperature conditions. [ABSTRACT FROM AUTHOR]

Physical properties of materials are mainly determined by valence electron configurations, where different valence shells would induce divergent phenomena. In compounds containing Sc2+, 3d electron occupancy is expected, the same as other transition metal atoms like Ti3+. But this situation still awaits experimental verification in inorganic materials. Here, we selected ScS to measure the valence electron density and orbital population of Sc2+ through delicate quantitative convergent‐beam electron diffraction. With the absence of 3d orbital features around Sc‐atom sites and the nearly bare population of t2g orbital, the unintuitive occupation of 4s orbital in Sc2+ is concluded. It should be the first time to report such a special electron configuration in a transition metal compound, in which 4s rather than 3d orbital is preferred. Our findings reveal the distinct behavior of Sc and probable ways to modulate material properties by controlling electron orbitals. [ABSTRACT FROM AUTHOR]

Conductive Ti3C2Tx MXenes have been widely investigated for the construction of flexible and highly‐sensitive pressure sensors. Although the inevitable oxidation of solution‐processed MXene has been recognized, the effect of the irreversible oxidation of MXene on its electrical conductivity and sensing properties is yet to be understood. Herein, we construct a highly‐sensitive and degradable piezoresistive pressure sensor by coating Ti3C2Tx MXene flakes with different degrees of in situ oxidation onto paper substrates using the dipping‐drying method. In situ oxidation can tune the intrinsic resistance and expand the interlayer distance of MXene nanosheets. The partially oxidized MXene‐based piezoresistive pressure sensor exhibits a high sensitivity of 28.43 kPa−1, which is greater than those of pristine MXene, over‐oxidized MXene, and state‐of‐the‐art paper‐based pressure sensors. Additionally, these sensors exhibit a short response time of 98.3 ms, good durability over 5000 measurement cycles, and a low force detection limit of 0.8 Pa. Moreover, MXene‐based sensing elements are easily degraded and environmentally friendly. The MXene‐based pressure sensor shows promise for practical applications in tracking body movements, sports coaching, remote health monitoring, and human–computer interactions. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries (ASSBs) using sulfide electrolytes have attracted ever‐increasing interest due to high ionic conductivity of the sulfides. Nevertheless, a thin, strong solid‐state sulfide electrolyte membrane maintaining high ionic conductivity is highly desired for ASSBs. Here, a thin, flexible composite solid electrolyte membrane composed of argyrodite sulfide Li6PS5Cl and a polar poly(vinylidene fluoride‐co‐trifluoroethylene) (P(VDF‐TrFE)) framework is prepared via an electrospinning‐infiltration‐hot‐pressing method. The interaction between Li6PS5Cl and polar P(VDF‐TrFE) ensures a high lithium‐ion conductivity (≈1.2 mS cm–1) at room temperature and good mechanical ductility of the composite electrolyte membrane. The coin‐type ASSB cells with the thin composite electrolyte membrane, a composite cathode of LiNbO3‐coated LiNi0.8Co0.1Mn0.1O2 and Li6PS5Cl, and a lithium‐indium anode, show super cycling performance, and the capacity retention is 92% after 1000 cycles and 71% even after 20 000 cycles at 1.0 mA cm–2 (i.e., 1.61 C) at room temperature. Moreover, pouch‐type ASSB cells with a high mass loading of active materials are made to demonstrate the potential and feasibility in future commercial applications. [ABSTRACT FROM AUTHOR]

High‐performance dielectric capacitors are critical for advanced electronics and electrical power systems. Polymeric dielectrics have been widely investigated for using in dielectric capacitors because of their high dielectric constants, flexibility, low density, and easy processability. However, it is still challenging to achieve simultaneous improvements in both energy density and efficiency in these dielectric polymers. Here, we report ferroelectric polyvinylidene‐fluoride‐based all‐organic dielectric polymer films with continuous compositional gradient structure are reported by modulating the spatial distribution of polymethyl‐methacrylate components, prepared via a facile and scalable additive manufacturing method. The continuous out‐of‐plane composition gradient in the all‐organic dielectric polymer films allows to tune electrical and mechanical behaviors, and thus induces a notably enhanced breakdown strength by modulating the electromechanical breakdown process related to the coupling of local electric field and stress. An ultrahigh discharge energy density of 38.8 J cm−3 along with a high discharge efficiency of >80% is achieved at the electric field of 800 kV mm−1 in the gradient polymer films, which is the highest energy density reported thus far in polymer‐based dielectrics including their nanocomposites and the highest energy efficiency achieved along with an energy density of >30 J cm−3. [ABSTRACT FROM AUTHOR]

Layered oxyselenides have been widely investigated as promising thermoelectric materials due to their unique merits such as super‐lattice structural features and intrinsic complexity, which contributes to low thermal conductivity and easily controllable electrical properties. Newly developed Bi2LnO4Cu2Se2 (Ln stands for lanthanide) oxyselenides are found to be potential thermoelectric systems since they have excellent electrical conductivity over 103 S cm−1. In this work, unique energy and time‐saving method combined self‐propagating high‐temperature synthesis (SHS) with spark plasma sintering (SPS) is adopted to successfully prepare a highly pure Bi2LnO4Cu2Se2 instead of a traditional solid‐state reaction. To explore the most suitable lanthanide for Bi2LnO4Cu2Se2, thermoelectric performance in a wide temperature range (300 to 923 K) of Bi2LnO4Cu2Se2 (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho, and Er) is deeply evaluated and studied. Ultimately, with a relatively high electrical conductivity, moderate Seebeck coefficient, and extremely low thermal conductivity, a maximum ZT value of ≈0.27 at 923K is achieved in Bi2DyO4Cu2Se2, which is 4 times larger than that of the ever‐reported Bi2YO4Cu2Se2 and proves a potential thermoelectric system for further investigation. This work may provide some enlightenment and broaden the horizon in finding new thermoelectric materials, especially for complex layered compounds. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries have emerged as a priority candidate for the next generation of safe and energy‐dense energy storage devices surpassing state‐of‐art lithium‐ion batteries. Among multitudinous solid‐state batteries based on solid electrolytes (SEs), sulfide SEs have attracted burgeoning scrutiny due to their superior ionic conductivity and outstanding formability. However, from the perspective of their practical applications concerning cell integration and production, it is still extremely challenging to constructing compatible electrolyte/electrode interfaces and developing available scale processing technologies. This review presents a critical overview of the current underlying understanding of interfacial issues and analyzes the main processing challenges faced by sulfide‐based all‐solid‐state batteries from the aspects of cost‐effective and energy‐dense design. Besides, the corresponding approaches involving interface engineering and processing protocols for addressing these issues and challenges are summarized. Fundamental and engineering perspectives on future development avenues toward practical application of high energy, safety, and long‐life sulfide‐based all‐solid‐state batteries are ultimately provided. [ABSTRACT FROM AUTHOR]

In recent years, the microstructure and physicochemical properties of high‐entropy ceramics have received much interest by the combination of multiple principal elements. Herein, (Ti0.2V0.2Cr0.2Nb0.2Ta0.2)2AlC–(Ti0.2V0.2Cr0.2Nb0.2Ta0.2)C high‐entropy ceramics (M2AlC‐MC HECs) were prepared by the spark plasma sintering (SPS) technique, attributing to the structural and chemical diversity of MAX phases. The microstructure of M2AlC‐MC HECs was characterized from micron to atomic scales, and the phase composition of M2AlC‐MC HECs was analyzed by a combination of Maud and Rietveld analysis. The results indicate the successful solid solution of Ti, V, Cr, Nb, and Ta atoms in the M‐site of the 211‐MAX configuration, and all the samples show a classic layered structure. The weight percentage of (Ti0.2V0.2Cr0.2Nb0.2Ta0.2)2AlC in the M2AlC‐MC HECs was more than 90%. Furthermore, the thermoelectric properties of M2AlC‐MC HECs were investigated for the first time in this study, and the electrical conductivity and thermal conductivity of HECs are 3278 S cm−1 and 2.78 W m−1 K−1at 298 K, respectively. [ABSTRACT FROM AUTHOR]

Li metal is the next‐generation anode material for high‐energy‐density Li‐ion batteries. Unfortunately, its practical application is hampered by drawbacks such as an unstable solid electrolyte interphase and undesirable Li dendrites. Herein, an Fe‐based protective layer with a valence gradient is constructed on Li anodes, which consists of an Fe3+/Fe2+‐rich outer layer and an Fe0‐containing inner layer. The protective layer not only isolates the underlying Li metal from the corrosive carbonate electrolyte, but also uniformly stores Li during plating and inhibits the growth of Li dendrites. The Li anode with the Fe‐based protective layer shows dendrite‐free Li plating/stripping behaviors; therefore, Li symmetric cells stably run for 1000 h at 1 mA cm‐2 and 1 mA h cm‐2 and even survive for 380 h at an ultra‐high capacity of 30 mA h cm‐2. With such a highly stable Li anode, LiFePO4 cells operate steadily for 1600 and 1000 cycles at 1 and 5 C, respectively. High‐loading LiCoO2 cells also present excellent cycling stability and rate capability, proving the advantages of the protective layer in Li anode protection. [ABSTRACT FROM AUTHOR]

Poor interfacial contacts between cathode active materials and solid‐state electrolytes in solid‐state lithium (Li) metal batteries often lead to a poor Li‐ion conductive pathway, and thus a short cycle life and a low energy density. In this work, we synthesized succinonitrile (SCN)‐based ionic conductors (ICs) with different flowability at room temperature for using in the composite cathodes and investigated the effect of the ICs on the cycle performance of the solid‐state Li metal batteries with a poly(vinylidene fluoride) (PVDF)‐based polymer electrolyte separator. Our results showed that the gel‐like SCN‐LiClO4 IC was superior to the flowable SCN‐LiTFSI [lithium bis(trifluoromethanesulfonyl)imide] IC and the rigid SCN‐LiClO4 IC. The gel‐like IC can build an effective Li‐ion conduction path in the cathodes, establish a stable cathode/electrolyte interface with a small interfacial resistance change during cycling, and allow a high mass loading of active materials, which enables a long cycle life and high energy density of solid‐state batteries. [ABSTRACT FROM AUTHOR]

Dielectric capacitors are an essential passive component widely used in integrated circuits. Recently, inkjet printing of 2D nanosheets into highly insulating layers has been developed for capacitor applications. However, the relatively low dielectric constant inherently associated with 2D nanosheets will hinder the rational design of high‐performance capacitor devices. In this work, the inks of high‐k Ca2NaNb4O13 perovskite nanosheets are formulated, and all‐printed dielectric capacitor consisting of Ca2NaNb4O13 films with commercial Ag electrodes is demonstrated. An average areal capacitance of ≈21 nF cm−2, together with low current density (<10−7 A cm−2) and low dielectric loss (≈2%), is achieved for the dielectric layer with thickness of ≈2 µm. The research shows that high‐k perovskite nanosheets have a great potential for applications in ink‐based additive manufacturing of flexible electronic devices. [ABSTRACT FROM AUTHOR]

Gaseous CO2 reduction driven by solar energy is a promising solution to the current energy crisis and environmental problems. Although thermocatalysts, electrocatalysts, and photocatalysts are developed as classical strategies for CO2 reduction, it remains a challenge for high efficiency and CO2 net reduction during this process. Here, a multi‐field driven hybrid catalyst, Pt/ZnO nanorod arrays/Bi1‐xErxCuSeO, is designed using the photo‐thermoelectric effect, which can take advantage of both photocatalysis and thermocatalysis. The results indicate that the maximum CO production rate of 2.91 µmol g−1 h−1 at 423 K can be realized in such Pt/ZnONR/Bi0.9Er0.1CuSeO hybrid catalyst, as can be ascribed to a synergetic photo‐thermoelectric effect (i.e., light irradiation can provide heat, photo‐excited carriers, and the concomitant Seebeck voltage). The band alignment of ZnO/BiCuSeO heterojunction and carriers transport are proposed to be optimized by the Er doped BiCuSeO thermoelectric supports, greatly enhancing the catalytic performance. The application of thermoelectric support could be promising in the structure design of multi‐field driven hybrid catalysts, and such a photo‐thermoelectric catalytic process demonstrates a desirable way of solar energy utilization in CO2 transformation. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries with conversion‐type cathodes promise to exceed the performance of lithium‐ion batteries due to their high theoretical specific energy and potential safety. However, the reported performance of solid‐state batteries is still unsatisfactory due to poor electronic and ionic conduction in the composite cathodes. Here, in situ formation of active material as well as highly effective ion‐ and electron‐conducting paths via electrochemical decomposition of Li6PS5Cl0.5Br0.5 (LPSCB)/multiwalled carbon nanotube mixtures during cycling is reported. Effectively, the LPSCB electrolyte forms a multiphase conversion‐type cathode by partial decomposition during the first discharge. Comprehensive characterization, especially operando pressure monitoring, reveals a co‐redox process of two redox‐active elements during cycling. The monolithic LPSCB‐based cell shows stable cycling over 1000 cycles with a very high capacity retention of 94% at high current density (0.885 mA cm−2, ≈0.7 C) at room temperature and a high areal capacity of 12.56 mAh cm−2 is achieved. [ABSTRACT FROM AUTHOR]

Ga‐doped ZnO (GZO) thin films grown on sapphire substrates have been widely investigated as a promising transparent thermoelectric (TE) material. However, due to the large lattice mismatch and thermal expansion between the sapphire substrate and GZO film, strain‐induced lattice distortion impedes the transport of electrons, leading to low carrier mobility. In this study, ZnO homo‐buffer layers with different thicknesses were inserted between sapphire substrates and GZO films, and their effect on the TE properties was investigated. A thin ZnO interlayer (10 nm) effectively reduced the lattice mismatch of the GZO film and improved the carrier mobility, which contributed to the large enhancement in the electrical conductivity. Simultaneously, energy filtering occurred at the interface between GZO and ZnO, resulting in a relatively high density of states (DOS) effective mass and maintaining a high Seebeck coefficient compared to that of the unbuffered GZO films. Consequently, the GZO film with a 10 nm thick ZnO buffer layer possessed a high power factor value of 449 μW m−1 K−2 at 623 K. This study provides a facile and effective method for optimizing the TE performance of oxide thin films by synergistically improving their carrier mobility and enhancing their effective mass. [ABSTRACT FROM AUTHOR]

Solid electrolytes (SEs) largely define the properties of all‐solid‐state batteries (ASSBs) and are expected to improve their safety, stability, and performance. Their ionic conductivity has much improved in recent years, enabling higher power and energy density. However, more subtle parameters, such as crystallinity, may also influence the electrochemical performance of cells. In this work, the correlation between the performance of ASSBs and thiophosphate SEs having the same stoichiometry, but different crystallinity is investigated. In In/InLi | SE | LiCoO2@ LiNb0.5Ta0.5O3 model cells, better cycling and rate performance is achieved when using glass/glass‐ceramic SEs (e.g., 75Li2S·25P2S5 glass, 70Li2S·30P2S5 glass, and Li6PS5Cl glass‐ceramic). This can be mostly attributed to the mitigation of contact loss by the glass/glass‐ceramic SEs compared to their crystalline SE counterparts. Furthermore, the SE decomposition at typical cathode potentials is investigated by using SE and carbon composites as cathodes. Larger volume changes and more severe decomposition are observed with crystalline SEs in the SE/carbon composite cathode after cycling. The crystalline SEs show higher electronic partial conductivity which results in more degradation in the composite cathode. This work sheds light on optimized composite cathode design for ASSB by carefully choosing solid electrolytes with appropriate mechanical and (electro‐)chemical properties. [ABSTRACT FROM AUTHOR]

Magnetic mixed‐phase materials with competing ground states are important from both scientific and technical points of view due to their magnetic phase transition and phase coexistence properties. Unlike artificially fabricated multi‐phase composites, it should be possible to modify their physical properties more efficiently by making use of the interphase coupling effects in mixed‐phase materials. In this study, the magneto‐transport properties are investigated to provide evidence of the existence of interphase coupling in a magnetic mixed‐phase system, specifically, Ni‐doped FeRh thin films. The rotation of the external magnetic field induces an emergent promotion effect of the antiferromagnetic (AFM)–ferromagnetic (FM) phase transition, which can be attributed to the modification of the magnetic free energy by interphase magnetic coupling across the AFM–FM phase boundary. The results shed light on the availability of an extra degree of freedom for manipulating the physical properties of material systems with mixed magnetic phases and help to further exploit their potential applications. [ABSTRACT FROM AUTHOR]