Design of an Ultra-Highly Stable Lithium-Sulfur Battery by Regulating the Redox Activity of Electrocatalyst and the Growth of Lithium Dendrite through Localized Electric Field.

Polysulfide shuttling and dendrite growth are two primary challenges that significantly limit the practical applications of lithium-sulfur batteries (LSBs). Herein, a three-in-one strategy for a separator based on a localized electrostatic field is demonstrated to simultaneously achieve shuttle inhibition of polysulfides, catalytic activation of the Li-S reaction, and dendrite-free plating of lithium ions. Specifically, an interlayer of polyacrylonitrile nanofiber (PNF) incorporating poled BaTiO (PBTO) particles and coating with a layer of MoS (PBTO@PNF-MoS) is developed on the PP separator.

Ultrasensitive electrochemical microRNA-21 detection based on MXene and ATRP photocatalytic strategy.

A TiCTMXene-based biosensor has been developed and the photocatalytic atom transfer radical polymerization (photo ATRP) amplification strategy applied to detect target miRNA-21 (tRNA). Initially, TiCTMXene nanosheets were synthesized from the TiAlC MAX precursor via selective aluminum etching. Then, functionalization of TiCTMXene nanosheets with 3-aminopropyl triethoxysilane (APTES) via silylation reactions to facilitate covalent bonding with hairpin DNA biomolecules specifically designed for tRNA detection.

Rational electrolyte design and electrode regulation for boosting high-capacity Zn-iodine fiber-shaped batteries with four-electron redox reactions.

Aqueous Zn ion-based fiber-shaped batteries (AZFBs) with the merits of high flexibility and safety have received much attention for powering wearable electronic devices. However, the relatively low specific capacity provided by cathode materials limits their practical application. Herein, we first propose a simple strategy for fabricating high-capacity Zn-iodine fiber-shaped batteries with a high concentration electrolyte and a reduced graphene oxide fiber (GF) cathode.

Gradiently Foaming Ultrasoft Hydrogel with Stop Holes for Highly Deformable, Crack-Resistant and Sensitive Conformal Human-Machine Interfaces.

Hydrogels are considered as promising materials for human-machine interfaces (HMIs) owing to their merits of tailorable mechanical and electrical properties; nevertheless, it remains challenging to simultaneously achieve ultrasoftness, good mechanical robustness and high sensitivity, which are the pre-requisite requirements for wearable sensing applications. Herein, for the first time, this work proposes a universal phase-transition-induced bubbling strategy to fabricate ultrasoft gradient foam-shaped hydrogels (FSHs) with stop holes for high deformability, crack-resistance and sensitive conformal HMIs. As a typical system, the FSH based on polyacrylamide/sodium alginate system shows an ultralow Young's modulus (1.

Synergistic Ion Sieve and Solvation Regulation by Recyclable Clay-Based Electrolyte Membrane for Stable Zn-Iodine Battery.

The high dissolution of polyiodides and unstable interface at the anode/electrolyte severely restrict the practical applications of rechargeable aqueous Zn-iodine batteries. Herein, we develop a zinc ion-based montmorillonite (ZMT) electrolyte membrane for synergizing ion sieve and solvation regulation to achieve highly stable Zn-iodine batteries. The rich M-O band and special cation-selective transport channel in ZMT locally tailor the solvation sheath around Zn and therefore achieve high transference number ( = 0.

High-Throughput Manufacturing of Multimodal Epidermal Mechanosensors with Superior Detectability Enabled by a Continuous Microcracking Strategy.

Non-invasive human-machine interactions (HMIs) are expected to be promoted by epidermal tactile receptive devices that can accurately perceive human activities. In reality, however, the HMI efficiency is limited by the unsatisfactory perception capability of mechanosensors and the complicated techniques for device fabrication and integration. Herein, a paradigm is presented for high-throughput fabrication of multimodal epidermal mechanosensors based on a sequential "femtosecond laser patterning-elastomer infiltration-physical transfer" process.

Tough Interfacial Adhesion Enabled Extremely Durable Flexible Supercapacitors.

The interfacial void and delamination between the hydrogel electrolyte and flexible electrode caused by the inconformal contact and weak adhesion lead to serious performance degradation of solid-state-sandwiched supercapacitors (SCs) upon repetitive deformation. Herein, we propose a hydrogel polymer electrolyte (HPE) engineering strategy for enhancing the interfacial adhesion (Γ) to achieve extremely durable SCs via the soft, tough, and self-adhesive HPE. Using a self-cross-linked poly(-hydroxyethyl acrylamide)/HPO (PHEAA/HPO) HPE as the model, the interfacial adhesion between HPE and polyaniline (PANI)-modified carbon cloth (CC) electrode (CC/PANI) reaches up to 556 J/m, leading to excellent durability of electrochemical performance under long-term repetitive deformations.

Identifying the Role of the Cationic Geometric Configuration in Spinel Catalysts for Polysulfide Conversion in Sodium-Sulfur Batteries.

An ABX spinel structure, with tetrahedral A and octahedral B sites, is a paradigmatic class of catalysts with several possible geometric configurations and numerous applications, including polysulfide conversion in metal-sulfur batteries. Nonetheless, the influence of the geometric configuration and composition on the mechanisms of catalysis and the precise manner in which spinel catalysts facilitate the conversion of polysulfides remain unknown. To enable controlled exposure of single active configurations, herein, Co and Co in CoO catalysts for sodium polysulfide conversion are in large part replaced by Fe and Fe, respectively, generating FeCoO and CoFeO.

Rheology Engineering for Dry-Spinning Robust N-Doped MXene Sediment Fibers toward Efficient Charge Storage.

MXene nanosheets are believed to be an ideal candidate for fabricating fiber supercapacitors (FSCs) due to their metallic conductivity and superior volumetric capacitance, while challenges remain in continuously collecting bare MXene fibers (MFs) via the commonly used wet-spinning technique due to the intercalation of water molecules and a weak interaction between Ti C T nanosheets in aqueous coagulation bath that ultimately leads to a loosely packed structure. To address this issue, for the first time, a dry-spinning strategy is proposed by engineering the rheological behavior of Ti C T sediment and extruding the highly viscose stock directly through a spinneret followed by a solvent evaperation induced solidification. The dry-spun Ti C T fibers show an optimal conductivity of 2295 S cm , a tensile strength of 64 MPa and a specific capacitance of 948 F cm .

Mechanisms for self-templating design of micro/nanostructures toward efficient energy storage.

The ever-growing demand in modern power systems calls for the innovation in electrochemical energy storage devices so as to achieve both supercapacitor-like high power density and battery-like high energy density. Rational design of the micro/nanostructures of energy storage materials offers a pathway to finely tailor their electrochemical properties thereby enabling significant improvements in device performances and enormous strategies have been developed for synthesizing hierarchically structured active materials. Among all strategies, the direct conversion of precursor templates into target micro/nanostructures through physical and/or chemical processes is facile, controllable, and scalable.

Nacre-Inspired Strong MXene/Cellulose Fiber with Superior Supercapacitive Performance via Synergizing the Interfacial Bonding and Interlayer Spacing.

MXene fibers are promising candidates for weaveable and wearable energy storage devices because of their good electrical conductivity and high theoretical capacitance. Herein, we propose a nacre-inspired strategy for simultaneously improving the mechanical strength, volumetric capacitance, and rate performance of MXene-based fibers through synergizing the interfacial interaction and interlayer spacing between TiCT nanosheets. The optimized hybrid fibers (M-CMC-1.

Ti C T MXene Ink Direct Writing Flexible Sensors for Disposable Paper Toys.

Flexible electronics have gained great attention in recent years owing to their promising applications in biomedicine, sustainable energy, human-machine interaction, and toys for children. Paper mainly produced from cellulose fibers is attractive substrate for flexible electronics because it is biodegradable, foldable, tailorable, and light-weight. Inspired by daily handwriting, the rapid prototyping of sensing devices with arbitrary patterns can be achieved by directly drawing conductive inks on flat or curved paper surfaces; this provides huge freedom for children to design and integrate "do-it-yourself (DIY)" electronic toys.

Bipolarized intrinsic faradaic layer on a semiconductor surface under illumination.

Interface charge transfer plays a key role in the performance of semiconductors for different kinds of solar energy utilization, such as photocatalysis, photoelectrocatalysis, photochromism and photo-induced superhydrophilicity. In previous studies, different mechanisms have been used to understand interface charge transfer processes. However, the charge transfer mechanism at the solid/liquid interface remains a controversial topic.

Green Flexible Electronics: Natural Materials, Fabrication, and Applications.

The emergence of plastic electronics satisfies the increasing demand for flexible electronics. However, it has caused severe ecological problems. Flexible electronics based on natural materials are increasing to hopefully realize the "green" and eco-friendly concept.

Tough Adhesive, Antifreezing, and Antidrying Natural Globulin-Based Organohydrogels for Strain Sensors.

Hydrogels are often used to fabricate strain sensors; however, they also suffer from freezing at low temperatures and become dry during long-time storage. Encapsulation of hydrogels with elastomers is one of the methods to solve these problems although the adhesion between hydrogels and elastomers is usually low. In this work, using bovine serum protein (BSA) as the natural globulin model and glycerol/HO as the mixture solvent, BSA/polyacrylamide organohydrogels (BSA/PAAm OHGs) were prepared by a facile photopolymerization approach.

A Review on the Prediction of Health State and Serving Life of Lithium-Ion Batteries.

The monitoring and prediction of the health status and the end of life of batteries during the actual operation plays a key role in the battery safety management. However, although many related studies have achieved exciting results, there are few systematic and comprehensive reviews on these prediction methods. In this paper, the current prediction models of remaining useful life of lithium-ion batteries are divided into mechanism-based models, semi-empirical models and data-driven models.

Photovoltage memory effect in a portable Faradaic junction solar rechargeable device.

Two-electrode solar rechargeable device is one of the promising technologies to address the problem of solar energy storage in large scale. However, the mechanism of dark output voltage remains unclear and the low volumetric energy density also limits its practical applications. Herein, we report that a Si/CoO/KBi/MnO Faradaic junction device exhibits a photovoltage memory effect, that is, the dark output voltage can precisely record the value of the photovoltage in the device.

Design of Vertically Aligned Two-Dimensional Heterostructures of Rigid TiCT MXene and Pliable Vanadium Pentoxide for Efficient Lithium Ion Storage.

Designing a thick electrode with appropriate mass loading is a prerequisite toward practical applications for lithium ion batteries (LIBs) yet suffers severe limitations of slow electron/ion transport, unavoidable volume expansion, and the involvement of inactive additives, which lead to compromised output capacity, poor rate perforamnce, and cycling instability. Herein, self-supported thick electrode composed of vertically aligned two-dimensional (2D) heterostructures (V-MXene/VO) of rigid TiCT MXene and pliable vanadium pentoxide are assembled an ice crystallization-induced strategy. The vertical channels prompt fast electron/ion transport within the entire electrode; in the meantime, the 3D MXene scaffold provides mechanical robustness during lithiation/delithiation.

Universal Strategy for Preparing Highly Stable PBA/TiCT MXene toward Lithium-Ion Batteries Chemical Transformation.

Prussian blue analogues (PBAs) are believed to be intriguing anode materials for Li storage because of their tunable composition, designable topologies, and tailorable porous structures, yet they suffer from severe capacity decay and inferior cycling stability due to the volume variation upon lithiation and high electrical resistance. Herein, we develop a universal strategy for synthesizing small PBA nanoparticles hosted on two-dimensional (2D) MXene or rGO (PBA/MX or PBA/rGO) an transformation from ultrathin layered double hydroxides (LDH) nanosheets. 2D conductive nanosheets allow for fast electron transport and guarantee the full utilization of PBA even at high rates; at the meantime, PBA nanoparticles effectively prevent 2D materials from restacking and facilitate rapid ion diffusion.

2D material-based peroxidase-mimicking nanozymes: catalytic mechanisms and bioapplications.

The boom in nanotechnology brings new insights into the development of artificial enzymes (nanozymes) with ease of modification, lower manufacturing cost, and higher catalytic stability than natural enzymes. Among various nanomaterials, two-dimensional (2D) nanomaterials exhibit promising enzyme-like properties for a plethora of bioapplications owing to their unique physicochemical characteristics of tuneable composition, ultrathin thickness, and huge specific surface area. Herein, we review the recent advances in several 2D material-based nanozymes, such as carbonaceous nanosheets, metal-organic frameworks (MOFs), transition metal dichalcogenides (TMDs), layered double hydroxides (LDHs), and transition metal oxides (TMOs), clarify the mechanisms of peroxidase (POD)-mimicking catalytic behaviors, and overview the potential bioapplications of 2D nanozymes.

Enhanced Jahn-Teller distortion boosts molybdenum trioxide's superior lithium ion storage capability.

Upgrading the energy density and cycling life of current lithium ion batteries is urgently needed for developing advanced portable electronics and electric vehicles. Amorphous transition metal oxides (TMO) with inherent lattice disorders exhibit enormous potential as electrode materials owing to their high specific capacity, fast ion diffusion, and excellent cyclic stability. Yet, challenges remain in their controllable synthesis.

Dual Enhancement of Sodium Storage Induced through Both S-Compositing and Co-Doping Strategies.

As a promising alternative to lithium-ion batteries (LIBs), rechargeable sodium-ion batteries (SIBs) are attracting enormous attention due to the abundance of sodium. However, the lack of high-performance sodium anode materials limits the commercialization of SIBs. In this work, the dual enhancement of SnS/graphene anodes in sodium storage is achieved through S-compositing and Co doping via an innovative one-step hydrothermal reaction at a relatively low temperature of 120 °C.

Tough, Transparent, and Anti-Freezing Nanocomposite Organohydrogels with Photochromic Properties.

Poor mechanical properties and freezing at low temperatures of traditional photochromic hydrogels limit their applications. Here, a novel type of photochromic nanocomposite organohydrogels (NC OGHs) by adding tungsten oxide nanoparticles was prepared by a simple one-pot method. The photochromic NC OGHs demonstrated excellent integrated properties, including high transparency, high mechanical properties, low-temperature resistance, anti-dehydration, rewrite capability, and UV blocking ability.

High-Performance Foam-Shaped Strain Sensor Based on Carbon Nanotubes and TiCT MXene for the Monitoring of Human Activities.

The flexible strain sensor is of significant importance in wearable electronics, since it can help monitor the physical signals from the human body. Among various strain sensors, the foam-shaped ones have received widespread attention owing to their light weight and gas permeability. However, the working range of these sensors is still not large enough, and the sensitivity needs to be further improved.

Site-Selective Transformation for Preparing Tripod-like NiCo-Sulfides@Carbon Boosts Enhanced Areal Capacity and Cycling Reliability.

Flexible power supply systems for future wearable electronics desperately require high areal capacity () and robust cycling reliability due to the limited surface area of the human body. Transition metal sulfides are preferred as cathode materials for their improved conductivity and rich redox centers, yet their practical applications are severely hindered by the sluggish charge transport kinetics and unavoidable capacity decay due to the phase transformation during charge/discharge processes. Herein, we develop a site-selective transformation strategy for preparing tripod-like NiCo-sulfides@carbon (T-NCS@C) arrays on carbon cloth.