Path Of Electrons Research Articles

Flux Growth and Surface Modification of Highly-Crystalline Active Materials and Solid Electrolytes for High Performance Libs

Materials for energy devices are often multicomponent with a number of interfaces and heterojunctions. In particular, lithium-ion batteries (LIBs) have been studied extensively because of their potential use as power sources. Recently, there has been a particular focus on all-solid-state LIBs (and high-performance LIBs). They have attracted considerable attention due to their high energy densities, which are the result of device miniaturization, and high safety due to their non-flammability. However, there is an extremely large innovation gap between general purpose LIBs and all-solid-state LIBs due to difficulties in the smooth transfer of lithium ions, i.e., the diffusion of lithium ions and electrons are disturbed at the interfaces of different solid materials. Therefore, we have tried to control and design their interfaces between active materials and solid electrolytes and fabricate materials for all-solid-state LIBs based on crystal science and engineering. Our research group has developed flux crystal growth and its extended methods for the preparation of high crystalline materials. Flux method is a liquid phase crystal growth in which idiomorphic highly crystalline particles can be obtained below the melting point of the target. Therefore, outmost crystal planes are tuned by our techniques where they have desired various ion and electron paths (i.e., hyper-spaces). In addition, the grown crystals are expected to have high crystallinity because diffusion and rearrangement of atoms easily occurred compared to conventional particle fabrication methods. Recently, we have developed a flux method to fabricate crystal layers on various substrates, which is called "flux coating method". For example, the target LIB-based materials are cathode active materials such as LCO, LNM, NCM, LFP and so on, anode active materials such as LTO, TNO and the related materials, and solid electrolytes such as LLZ, LLT, LLN, etc. and their crystal layers. Furthermore, their surface conditions are precisely controlled in our laboratory. Details on material design and hyperspace control of flux-grown crystalline particles and crystal layers via flux-related techniques will be reported at the 244th ECS Meeting.

Rational Design of a Cost-Effective Biomass Carbon Framework for High-Performance Lithium Sulfur Batteries

Lithium–sulfur (Li-S) batteries are the most attractive candidates for next-generation large-scale energy storage because of their high theoretical energy density and the affordability of sulfur. However, most of the reported research primarily concentrates on low sulfur loading (below 2 mgs cm−2) cathodes using binders and traditional collectors, thus undermining the expected energy density. Herein, a N, O co-doped carbon nanotube (N, O-CNT) decorated wood framework (WF), denoted as WF-CNT, was designed as a free-standing sulfur host, achieving high sulfur loading of 10 mgs cm−2. This unique cathode featured low tortuosity microchannels and a conductive framework, reducing the diffusion paths for both ions and electrons and accommodating the volume changes associated with sulfur. Moreover, the internal CNT forests effectively captured soluble lithium polysulfides (LiPSs) and catalyze their redox kinetic. Consequently, the S@WF-CNT-800 sample exhibited a high initial discharge capacity of 1438.2 mAh g−1 at a high current density of 0.5 A g−1. Furthermore, a reversible capacity of 404.5 mAh g−1 was obtained after 500 cycles with sulfur loading of 5 mgs cm−2 at 0.5 A g−1. This work may support the development of high sulfur loading cathodes utilizing cost-effective and sustainable biomass materials for Li-S batteries.

Low-dimensional heat conduction in surface phonon polariton waveguide

Heat conduction in solids is typically governed by the Fourier’s law describing a diffusion process due to the short wavelength and mean free path for phonons and electrons. Surface phonon polaritons couple thermal photons and optical phonons at the surface of polar dielectrics, possessing much longer wavelength and propagation length, representing an excellent candidate to support extraordinary heat transfer. Here, we realize clear observation of thermal conductivity mediated by surface phonon polaritons in SiO2 nanoribbon waveguides of 20-50 nm thick and 1-10 μm wide and also show non-Fourier behavior in over 50-100 μm distance at room and high temperature. This is enabled by rational design of the waveguide to control the mode size of the surface phonon polaritons and its efficient coupling to thermal reservoirs. Our work laid the foundation for manipulating heat conduction beyond the traditional limit via surface phonon polaritons waves in solids.

Synthesis of nanoscale LiCoPO4/C between few-layer graphene and its influence on electrochemical performance for lithium-ion batteries

In this study, the composite cathode material of LiCoPO4/C and graphene is synthesized using solvothermal method assisted by oleylamine. The effect of graphene addition on the material properties is fully investigated, and the synergistic effect of amorphous carbon and graphene is also studied. Graphene serves as a conductive skeleton and provides abundant diffusion paths for electrons. The nanoscale LiCoPO4 material synthesized by solvothermal method is evenly distributed around the few-layer graphene with the assistance of oleylamine, and the amorphous carbon formed after the pyrolysis of oleylamine at high temperature tightly connects LiCoPO4 to the graphene, which improves the conductivity and electrochemical performance of the sample. The results of characterization reveal that adding graphene can prepare LiCoPO4 materials with good crystallization and improve the specific surface area and pore size of the material. At the same time, the amorphous carbon and graphene inside the material also show a good degree of graphitization. Electrochemical test results show that doping graphene with a mass ratio of 6% can enhance the electrochemical performance and cycle stability of LCPC-6%G sample. The initial discharge capacity of LCPC-6%G sample reaches 157.2 mA h g−1 at 0.1 C. In this study, nanoscale LiCoPO4 samples are successfully synthesized on the surface of graphene, which provides a new idea for the preparation of nanoelectrode materials and conductive skeleton composite samples.

Ultra-thin nanohoneycomb porous CoMoO4 with excellent catalytic performance for water splitting at large current densities

Electrocatalytic water splitting for hydrogen production is considered the most effective and cleanest strategy to make full use of renewable energy. It still lacks the highly efficient and stable bifunctional catalyst to deliver high current density for large scale application of water splitting. Here, we innovatively developed a facile method to synthesize a three-dimensional (3D) honeycomb porous CoMoO4@pNi (porous nickel) catalyst with ultra-thin nanosheet, the generated oxygen vacancies and mesoporous structures with defects as active sites. We also precisely tuned the thickness and array structure to investigate its catalytic performance. The as-prepared CoMoO4@pNi catalyst delivers the overpotential of 377 mV for HER and 410 mV for OER, respectively, and only demands 1.99 V to reach a large current density of 1000 mA cm−2 for overall water splitting. CoMoO4@pNi catalyst is also operated for 200 h under 500 and 1000 mA cm−2, respectively, and both showed an ignorable current decrease. The excellent activity and stability are ascribed to the high surface area, short transport path for electrons and protons, the full contact between the exposed active sites and electrolyte, and the inherent stable nanohoneycomb porous structure of the ultra-thin nanosheet.

Effects of deposited particle energy on the structure and properties of diamond-like carbon films

Using plasma-enhanced chemical vapor deposition (PECVD), a series of diamond-like carbon (DLC) films were prepared on YG8 carbide substrate by changing the enhancement mode and the negative bias voltage of the substrate. The structure and properties of the deposited films were tested by a series of analytical and testing instruments.During the deposition of DLC films, the ability of electrons to collide and ionize the gas is enhanced by increasing the number of electrons and extending the movement path of electrons, which is called electron-assisted enhanced gas ionization. Four different experimental modes (A mode, B mode, C mode, D mode) were set up. Different experimental modes have different degrees of electron-assisted enhancement ability of gas ionization, so different experimental modes are called different enhancement modes. The ions ionized by the electrons participate in the deposition of the film under the traction of the negative bias voltage of the substrate. The results show that: when depositing diamond-like carbon films, the energy of the ion beam is indirectly affected by electron collisions in different enhancement modes and directly affected by the negative bias voltage of the substrate. The higher the enhancement mode, the higher the ion beam energy. The higher the substrate negative bias voltage, the higher the ion beam energy generated by gas source discharge. Under the dual action of enhancement mode and substrate negative bias voltage, the total energy of ions involved in deposition should not be too high or too low, and the synergy of the two makes the properties and quality of the deposited film reach a better value. For industrial large-scale production of tool protection film for cutting aluminum alloy, it is more suitable for high enhancement mode and low negative bias voltage production.Through a series of process optimization to improve and enhance the comprehensive performance of DLC film, it is further applied to the actual processing application field, which has great industrial and social value to realize the large-scale application of DLC film in the field of hard to cut metal processing.

CNTs and rGO synergistically enhance the cycling stability of yolk-shell silicon anodes for efficient lithium storage

Si-based anode materials have received a lot of attention from researchers due to their ultra-high theoretical specific capacity. However, poor conductivity and volume expansion during cycling have seriously hindered their further commercialization. To address the problems of Si-based materials, the multidimensional carbon materials constructed from Zeolitic imidazolate framework (ZIF) derived carbon and carbon nanotubes (CNTs) followed by the addition of reduced graphene oxide (rGO) are employed to encapsulate silicon nanoparticles (Si@C-ZIF@CNTs@rGO) to prepare a composite anode with a yolk-shell structure, which are prepared by mechanical stirring, electrostatic self-assembly and two-step calcination. The heat-treated ZIF materials not only form a unique yolk-shell structure that can effectively inhibit the volume expansion of silicon nanoparticles, but also derive rigid carbon shells and carbon nanotubes to improve the electrical conductivity of the anode materials, while rGO introduced by electrostatic self-assembly provides a large number of transport paths for electrons and ions. In a full battery test composed of LiFePO4 cathode, the composite cathode material loses only 2.4 % of its specific capacity after 100 cycles at 0.5 C current density. This work provides new ideas for multidimensional carbon structures to improve the lithium storage performance of silicon-based anodes.

Blue phosphorus phase GeSe monolayer for nitrogenous toxic gas sensing: A DFT study

Continuing industrialization, a variety of toxic gases are emitted into the air, yet gas concentrations at low levels are extremely hard to detect. So the development of high-performance toxic gas sensors is imminent. Two-dimensional materials with advantages such as large specific surface area and unique electronic properties open new paths for gas sensors. In this study, a monolayer of blue phosphorus phase germanium selenide (GeSe) was used as the substrate material. The absorption performance of ambient nitrogenous toxic gases (NO, NO2, NH3, N2O) on the surface of GeSe monolayers was explored by the density-functional theory (DFT) calculations. The results show that the interaction between GeSe and the four gases exhibits physisorption. Based on four optimal adsorption structures, Bader charge, work function, band structure, density of states, and recovery time were calculated. Charge transfer is promoted due to the presence of GeSe intrinsic dipoles and only NH3 was found to be the charge donor. The significant changes in work function and electronic properties of GeSe monolayer adsorption of NO indicate significant changes in electrical signals during gas detection. This work reveals that GeSe monolayer has higher sensitivity and selectivity for NO hazardous gas.

Giant quantum oscillations of acoustoelectric current in narrow graphene nanoribbons

A theory is presented for the acoustoelectric (AE) effect in narrow graphene nanoribbons (GNRs) deposited on a piezoelectric substrate when a surface acoustic wave (SAW) is launched onto the surface of the piezoelectric. It is assumed that the electron density in such GNRs can be controlled by applying an external gate voltage, and the acoustic wavelength is much smaller than the mean free path of electrons, so that the quantum mode of interaction of those electrons with the SAW in realized. Using the kinetic theory approach, we calculate the AE current flowing through the GNR sample and arising as a result of momentum transfer from coherent SAW phonons to conduction electrons. It is shown that size quantization of the electron energy spectrum in narrow GNRs leads to giant periodic oscillations of the AE current with a change in the gate voltage. AE current surges occur whenever the Fermi level, rising with increasing gate voltage, crosses in turn the bottom of each of the successive size-quantized electron energy subbands. The oscillations predicted are giant in the sense that the maximum values of the current exceed its minimum values by at least an order of magnitude, and they can be observed in narrow GNRs ∼10 nm wide even at room temperature.

Controlled synthesis of transition metal oxide multi-shell structures and in situ study of the energy storage mechanism

Multi-shell transition metal oxide hollow spheres show great potential for applications in energy storage because of their unique multilayered hollow structure with large specific surface area, short electron and charge transport paths, and structural stability. In this paper, the controlled synthesis of NiCo2O4, MnCo2O4, NiMn2O4 multi-shell layer structures was achieved by using the solvothermal method. As the anode materials for Li-ion batteries, the three multi-shell structures maintained good stability after 650 long cycles in the cyclic charge/discharge test. The in situ transmisssion electron microscope characterization combined with cyclic voltammetry tests demonstrated that the three anode materials NiCo2O4, MnCo2O4 and NiMn2O4 have similar charge/discharge transition mechanisms, and the multi-shell structure can effectively buffer the volume expansion and structural collapse during lithium embedding/delithiation to ensure the stability of the electrode structure and cycling performance. The research results can provide effective guidance for the synathesis and charging/discharging mechanism of multi-shell metal oxide lithium-ion battery anode materials.

Universal high-performance bulk graphites from natural flake graphite by rapid sintering

High performance graphites (HPGs) are a key material in modem industries; however, prevailing HPGs are short of comprehensive properties in many aspects, i.e., a specific property of HPGs is always achieved at the cost of other properties. And the production of HPGs is highly costly and causes severe environmental problems. Current HPGs are derived from various carbonaceous precursors, excluding nature flake graphite (NFG), the best graphite source. Typically, NFG-based bulk graphite has poor mechanical properties because NFG is difficult to sinter. Here we report the preparation and comprehensive properties of a new family of universal HPGs (U-HPGs) that can be mass-produced with moderate conditions by sintering NFG slightly mixed with diamond, where units of onion carbon (OC) with NFG (OC@NFG) act as building blocks. OC@NFG creates a strong interfacial network between the NFGs, giving the U-HPGs outstanding strength and moderate hardness. With U-HPGs being more than 93 % graphitization, the flexural strength exceeds 100 MPa, far superior to mainstream commercial graphites. OC@NFG also bestows U-HPGs with excellent thermal conductivity(＞125 W m−1 K−1 at room temperature). For such structure provides a 3D path for electrons inside U-HPGs, the as-produced material has significant electronical conductivity. This work presents new insights into this old yet important material and allows for innovative design of HPGs for various applications.

Cobalt carbonate hydroxide-embedded in multi-layered holey nanoflower cross-linked with carbon nanotube for highly efficient supercapacitors with ultrahigh rate performance

In this work, bimetallic nickel-cobalt based metal organic framework (MOF) is in-situ grown on 2D laminar Co2(OH)2CO3 with multi-walled carbon nanotubes (MWCNTs) aid to form nanoflower-like hierarchical porous heterogeneous structure for advanced supercapacitor application. Benefitting from the low crystal surface energy of Co2(OH)2CO3, its intersection and connection with MOF generate convenient electron path and open channel for ionic transmission, and large contact area. The high aromaticity of MWCNTs slows down destruction for MOF structure from water molecule through providing hydrophobic environment, guaranteeing stable presence of the resulting composite in aqueous electrolyte. The synergistic effect of Ni/Co with high redox activity in bimetallic NiCo-MOF provides rapid and multiple redox reactions for enhanced capacitance. Taking full advantage of promising merits of individual components, the optimized NiCo MOF-Co2(OH)2CO3 nanosheet-MWCNT30 (NCM-NS-CNT30) composite under MWCNT dosage of 30 mg delivers greatly enhanced specific capacitance (1773 F g−1 at 1 A g−1) and obviously improved rate performance (96.5 % retention at 10 A g−1). Based on it, the fabricated hybrid supercapacitor (HSC) NCM-NS-CNT30//AC presents comparatively good energy density (30.625 Wh Kg−1), superior to most recently reported Ni, Co-based supercapacitors.

P-doped nanorod MoO3 and nanoflower NiAl-LDH construct S-type heterojunction for photocatalytic high-efficiency hydrogen evolution

S-type heterojunction is a new type of photocatalytic heterojunction that can efficiently enhance the performance of photocatalytic hydrogen-producing. In this paper, NiAl-LDH/P-MoO3 composite catalysts were prepared, NiAl-LDH, P-MoO3 and NiAl-LDH/P-MoO3 were characterized, tested and analyzed from the aspects of morphology, structure and spectrum. The 5 h hydrogen-producing amount of NiAl-LDH/P-MoO3 reaches 298.72 μmol, which is 160 times and 16 times that of MoO3 and NiAl-LDH under the visible light, respectively. The doping of P narrows the band gap of MoO3 and is more helpful to the electronic transmission. The irregular P-MoO3 nanorods with a diameter of about 200 nm are attached to 3-4 μml NiAl-LDH nanoflower. The construction of S-type heterojunction changes the electronic transmission pathway of NiAl-LDH/P-MoO3 while improving the electron-hole pair separation ratio of NiAl-LDH/P-MoO3. The strong oxidizing ability of P-MoO3 and the strong reducing ability of NiAl-LDH are retained. Effective control of electronic transmission path improves the photocatalytic hydrogen-producing activity and stability of NiAl-LDH/P-MoO3, which provides a certain theoretical support for the realization of photocatalytic high-efficiency HER by constructing heterojunction.

Facile synthesis of ultrafine RuTe2 nanoparticles supported on B, N co-doped graphene as an efficient HER catalyst

Recently, ruthenium telluride (RuTe2) has received widespread attention as an effective HER catalyst. In this work, ultrafine and well-dispersed RuTe2 nanoparticles anchored on nitrogen and boron co-doped graphene (RuTe2/BNG) was developed by freeze-drying and facile pyrolysis method, demonstrating a brilliant HER performance. The overpotential of RuTe2/BNG at the current density of 10 mA cm−2 is only 34 and 16 mV in 0.5 M H2SO4 and 1.0 M KOH solution, respectively. More importantly, the RuTe2/BNG can also maintain significantly robust HER stability during long-term chronopotentiometry measurements. The outstanding HER activity of RuTe2/BNG should be ascribed to its properties with abundant defects, large specific surface area, high electronic conductivity and short mass transfer path. Our work offers a new path to fabricate efficient HER catalysts by homogeneously anchoring RuTe2 on B, N co-doped graphene.

Enhanced photocatalytic degradation of tetracycline by improving electron flux at the Schottky junction between Bi nanoparticles and MoS2-anchored RGO

In this work, a heterostructured metallic Bi/MoS2 photocatalyst (MBix) was prepared via uniform decoration of plasmonic bismuth nanoparticles onto the surface of MoS2 nanosheets. MBix catalysts were then loaded onto the surface of reduced graphene oxide (RGO) using a simple hydrothermal method to form RGO/MBix nanocomposite. RGO/MBix heterostructures demonstrated significantly improved photocatalytic performance for the removal of tetracycline (TC) under visible-light irradiation. The enhanced photocatalytic activity was found to be dependent on the level of Bi and RGO in the catalyst. The degradation rate over the optimum catalyst (RGO-2.5/MBi1.0) was six-fold higher than that of pristine MoS2. The enhanced photocatalytic activity was due to the improved light-harvesting and promoted separation efficiency of carrier pairs through the local surface plasmonic resonance (LSPR) effect of Bi nanoparticles and thus effective electron migration in Bi/MoS2 hetero-interface. Moreover, reduced graphene oxide (RGO) as a supreme electron sink provided a conduction path for excited electrons, and further decreased the rate of electron-hole recombination. The reduced charge recombination was well supported by photoluminescence and electrochemical impedance analyses. The radical trapping experiments indicated that the hydroxyl and superoxide radicals were the main active species to initiate TC degradation. Developing earth-abundant Bi-based photocatalysts, as well as the facile and economical approach to fabricating LSPR-enhanced composite will provide new insights into replacing the noble metals materials for environmental remediation.

Covalently bridge metals to biomass carbon for sensing DA and FA with high specificity and sensitivity

Due to the high catalytic activity and electrical conductivity, “transition metal-nonmetal” compounds have broad application prospects in the construction of electrochemical sensors. However, it is still a challenge to solve the problem of catalyst deactivation and slow electron transfer due to nanoparticle agglomeration's blockage of active sites. Here, we prepare a series of covalently bonded “C-M-O” bridge bonds on biomass carbon for the first time. The bridge bonds have a straight-like “electron path”, which shortens the electron transfer path and improves the electrical conductivity, and catalytic activity. The bridge bonds exhibit excellent catalytic activity even after being subjected to prolonged mechanical external forces. Besides, the bridge bonds can integrate a biosensor with MIP and exhibit excellent electrocatalytic performance, including high sensitivity, low detection limit, excellent stability, superior interference immunity, and the ability to accurately monitor DA and FA released from real samples and live cells in real time. The strategy of forming “C-M-O” bridge bonds based on covalently bonded supports provides a new perspective for solving the agglomeration of nanocatalysts blocking active site deactivation and improving electron transfer rate.

Development of an electron track-structure mode for arbitrary semiconductor materials in PHITS

Abstract Optimizing the design of semiconductor detector requires an electron track-structure code that can trace an incident electron motion with energies down to a few eV and simulate the production process of excited electrons in semiconductors. We therefore developed an Electron Track Structure mode applicable to ARbitrary Targets (ETSART) and implemented it into Particle and Heavy Ion Transport code System (PHITS). ETSART can simulate the electrons’ motion in arbitrary semiconductor materials using their bandgap energies. The accuracy of ETSART was validated by comparing the calculated electron path lengths in semiconductor materials with the corresponding data in the ICRU Report 37. Using ETSART, we also computed the mean energy required to produce an electron–hole pair (epsilon value) in various semiconductors and found that the epsilon value varies nonlinearly with the bandgap energy. Thus, ETSART can be useful for initial and mechanistic evaluations of electron–hole pair formation in new materials.

High-harmonic generation in liquids with few-cycle pulses: effect of laser-pulse duration on the cut-off energy.

High-harmonic generation (HHG) in liquids is opening new opportunities for attosecond light sources and attosecond time-resolved studies of dynamics in the liquid phase. In gas-phase HHG, few-cycle pulses are routinely used to create isolated attosecond pulses and to extend the cut-off energy. Here, we study the properties of HHG in liquids, including heavy water, ethanol and isopropanol, by continuously tuning the pulse duration of a mid-infrared driver from the multi- to the two-cycle regime. Similar to the gas phase, we observe the transition from discrete odd-order harmonics to continuous extreme-ultraviolet emission. However, the cut-off energy is shown to be entirely independent of the pulse duration. These observations are confirmed by ab-initio simulations of HHG in large liquid clusters. Our results support the notion that the cut-off energy is a fundamental property of the liquid, independent of the driving-pulse properties. Our work implies that few-cycle mid-infrared laser pulses are suitable drivers for generating isolated attosecond pulses from liquids and confirm the capability of high-harmonic spectroscopy to determine the mean-free paths of slow electrons in liquids.

High-harmonic spectroscopy of low-energy electron-scattering dynamics in liquids

High-harmonic spectroscopy is an all-optical nonlinear technique with inherent attosecond temporal resolution. It has been applied to a variety of systems in the gas phase and solid state. Here we extend its use to liquid samples. By studying high-harmonic generation over a broad range of wavelengths and intensities, we show that the cut-off energy is independent of the wavelength beyond a threshold intensity and that it is a characteristic property of the studied liquid. We explain these observations with a semi-classical model based on electron trajectories that are limited by the electron scattering. This is further confirmed by measurements performed with elliptically polarized light and with ab-initio time-dependent density functional theory calculations. Our results propose high-harmonic spectroscopy as an all-optical approach for determining the effective mean free paths of slow electrons in liquids. This regime is extremely difficult to access with other methodologies, but is critical for understanding radiation damage to living tissues. Our work also indicates the possibility of resolving subfemtosecond electron dynamics in liquids offering an all-optical approach to attosecond spectroscopy of chemical processes in their native liquid environment.

A braided flexible Zn–MnO2 yarn battery based on cobweb-like carbonized polypyrrole modified carbon fiber electrodes

Flexible zinc ion batteries (ZIBs) are promising candidates for energy storage devices because of high safety and low cost. Carbon fibers (CFs) are ideal current collectors for ZIBs due to their good flexibility, electrical conductivity and corrosion resistance. Herein, a novel CFs-based current collector is proposed. At first, the inertness and non-polarity of CFs were significantly modified by activating and etching to obtain a multi-layered porous structure. Thereafter, carbonized polypyrrole (CPPy) nanowire conductive networks were built up on etched carbon fibers (ECFs) by electrochemical in situ growth and carbonization. Based on the CPPy network, MnO2 nanoflowers were grown firmly by the hydrothermal method to construct multi-layer MnO2@CPPy@ECFs composite electrode. The multi-layered 3D CPPy conductive network is rooted in MnO2, providing a dedicated transmission path for both electrons and ions during electrochemical redox reactions. The MnO2@CPPy@ECFs electrode had an initial capacity of 346.1 mA h·g−1 at 0.1 A g−1 and 252.8 mA h·g−1 after 800 cycles. In addition, the integrated flexible Zn–MnO2 2D fabric battery with MnO2@CPPy@ECFs fabric cathode shows a specific capacity of 254.7 mA h·g−1 at 0.1 A g−1. Finally, a flexible Zn–MnO2 yarn battery with high flexibility, shape adaptability, structural integrity and good mechanical stability was fabricated by the 2D braid method. The initial specific capacity of the flexible Zn–MnO2 yarn battery is 111.7 mA h·g−1 at 0.1C, which also presents a remarkable volumetric energy density of 30.5 mW h cm−3. This work opens up a new pathway for the rational design of flexible electrodes for wearable ZIBs.