Conductive Skeleton Research Articles

Redox-Bipolar Covalent Organic Framework Cathode for Advanced Sodium-Organic Batteries.

Redox-active covalent organic frameworks (COFs) are promising candidates for sodium-ion batteries (SIBs). However, the construction of redox-bipolar COFs with the anions and cations co-storage feature for SIBs is rarely reported. Herein, redox-bipolar COF constructed from aniline-fused quinonoid units (TPAD-COF)is developed as the cathode material in SIBs for the first time. The unique integration of conductive aniline skeletons and quinone redox centers endows TPAD-COF with high ionic/electrical conductivity, abundant redox-active sites, and fascinating bipolar features. Consequently, the elaborately tailored TPAD-COF cathode exhibits higher specific capacity (186.4mAhg-1 at 0.05Ag-1) and superior cycling performance (over 2000 cycles at 1.0Ag-1 with 0.015% decay rate per cycle). Impressively, TPAD-COF also displays a high specific capacity of 101mAhg-1 even at -20°C. As a proof of concept, all-organic SIBs (AOSIBs) are assembled using TPAD-COF cathode and disodium terephthalate anode, which also show impressive electrochemical properties, indicating the potential application of TPAD-COF cathode in AOSIBs. The work will pave the avenue toward advanced COFs cathode for rechargeable batteries through rational molecular design.

Hybrid 2D/3D carbon framework confined Si with optimized reaction kinetics for highly stable Li-Ion storage

Three-dimensional (3D) conductive skeletons can optimize electron/Li-ion migration kinetics and alleviate stress accumulation for silicon (Si)-based electrodes. In this study, the modified carbon nanotubes (MCNs) are used as a stress-buffering and high-speed conducting framework, and a hierarchical structure of 3D MCNs interspersed with flour-derived 2D N-doped C layer is designed for Si anode via molecular self-assembly and in-situ carbonization strategies. Experimental and theoretical calculations show that the charge redistribution occurred in the fabricated SiOx and N-doped C interfaces, which induced an electric field response and increased the interfacial electron/Li-ion transfer rate. Multiphysics simulations show that the 2D/3D hierarchical structures of carbon can optimize the physicochemical properties, such as a favorable local electronic environment, flexible stress dissipation mechanisms and good thermal stability. The prepared electrode with 77.1 wt% Si@SiOx shows a low volume expansion rate of 23 % and has an excellent Li-ion storage capability (972.1 mAh g−1 at 4000 mA g−1). Moreover, the structural stability of fabricated Si-based electrodes is enhanced, achieving 0.04 % per cycle capacity decay for 500 cycles at 2000 mA g−1. Such integrating the 2D/3D carbon framework to manipulate Si interfacial properties provides fundamental research for other electrodes plagued by significant volume expansion.

Interlayer engineering of V2O5·nH2O by conductive Ni-BTA enabling high-performance aqueous ammonium ion batteries

Aqueous ammonium ion batteries (AAIBs) are of interest due to the low molar mass, small hydration radius, abundant raw materials and high safety of the carrier ammonium-ion. Nevertheless, there are numerous constraints associated with electrode materials that are suitable for ammonium-ion storage. In this study, we design and synthesize a composite comprising of one-dimensional conductive metal-organic skeleton material (1D c-MOF) embedded between layers of hydrated vanadium pentoxide (VOH) with improved ammonium-ion storage. The central ion of the 1D c-MOF is selected to be the nickel ion, while the ligand is 1,2,4,5-benzenetetramine (BTA). The incorporation of Ni-BTA between the vanadium oxide layers results in the formation of a composite (Ni-BTA/VOH) exhibiting enhanced structural stability, augmented layer spacing and elevated conductivity. Furthermore, the dual energy storage mechanisms of VOH and CN rearrangement act in concert to yield a “1+1 > 2” effect, thereby markedly enhancing the ammonium-ion storage. The specific capacity of Ni-BTA/VOH can reach 183 mAh g−1 at 0.2 A g−1, and the retention rate can reach 52.5 % after 500 cycles at 2 A g−1. This work not only proves the potential of Ni-BTA/VOH for widespread application in the field of aqueous batteries, but also provides a new method for structural engineering of VOH with boosted ammonium-ion storage properties.

CoAl-LDH on ZIF-67 template inserted into the conductive matrix as a high-efficiency composite anode for facilitating phosphorus elimination

Phosphorus pollution can induce water eutrophication and critically threaten the stability of the aquatic ecosystem. Capacitive deionization (CDI) is a potential candidate for controlling phosphorus levels due to its lack of chemical requirements, eco-friendliness, and low energy demand. Herein, a novel ZIF-67-derived CoAl-LDH embedded in conductive carbon skeletons (CoAl-LDH/C) was successfully constructed by a self-sacrificial template strategy. A conductive carbon matrix is incorporated into LDH, which can alleviate the insufficient conductivity and aggregation issues for LDH. The results revealed that CoAl-LDH/C possesses superior phosphorus elimination properties (qm=32.7 mg P/g) at 1.2 V, benefiting from its abundant active sites, large mesoporous diameter, specific surface area, total pore volume, outstanding specific capacitance, and ion diffusion. Meanwhile, the energy consumption of CoAl-LDH/C is merely 3.398 kWh/kg and 0.024 kWh/m3. CoAl-LDH/C also proved flexible for practical applications regarding complex water quality (wide pH range, coexisting substances, natural water) and cyclic utilization. Finally, the potential mechanism illuminated that the phosphorus elimination process in an electric field engages with ligand exchange, anion exchange, electrostatic attraction, and hydrogen bonds. This work paves a promising concept for designing innovative LDH-based electrodes with excellent ion diffusion and superior conductivity to eliminate phosphorus efficiently.

Biomimetic Ambient‐Pressure‐Dried Aerogels with Oriented Microstructures for Enhanced Electromagnetic Shielding

AbstractOriented aerogels, emerging as a new generation of lightweight electromagnetic interference (EMI) materials, often face complex synthesis processes. While creating an orderly oriented microstructure for EMI aerogels through ambient pressure drying (APD) shows promise, it remains a significant challenge. Here, inspired by the directional grown structure of the plant, a new strategy that employs rapid precursor orientation followed by slow cross‐linking to achieve the APD of directional EMI aerogels is proposed. This approach demonstrates that low‐temperature oriented polymerization of polyaniline enables strong cross‐linking with poly(3,4‐ethylenedioxythiophene) and alginate, forming a robust conductive directional skeleton and mitigating surface tension issues during mild drying. The resulting aerogel features high conductivity (48.84 S m−1), excellent flame retardancy, and impressive compressive strength. Notably, its sturdy frame allows for further enhancement with other functional materials, such as Mxene, through re‐processing and re‐drying. The tree‐branch‐like aerogel achieves a significantly improved EMI shielding effectiveness of 50.3 dB across an ultrawideband range of 8.2–40 GHz. This strategy offers a new idea for the straightforward preparation of functional aerogels with programmability and oriented microstructures using ambient drying.

Highly Conductive Two-Dimensional FeTHBQ/Graphene Nanocomposite as the Cathode Material for Lithium-Ion Batteries.

Constructing high-performance coordination polymer (CP) cathodes for lithium-ion batteries based on the redox reactions of both high-potential transition metal ions and high-capacity organic ligands has attracted extensive attention. However, CP cathodes suffer from structural degradation, low electrical conductivity, and sluggish diffusion kinetics, resulting in poor cycling stability and inferior rate capability. Herein, the ultrafine FeTHBQ (THBQ = tetrahydroxy-1,4-benzoquinone) CP nanoparticles in situ grew on both sides of graphene nanosheets to form the uniform two-dimensional (2D) FeTHBQ/Graphene nanocomposite with a sandwich structure via a one-pot solvothermal method. The highly conductive graphene skeleton promotes the electronic conduction and structural stability for the 2D FeTHBQ/Graphene nanocomposite. Besides, compared with bulk FeTHBQ, the primary FeTHBQ nanoparticles in the FeTHBQ/Graphene nanocomposite have smaller particle sizes with larger specific surface areas. This not only shortens the Li+ diffusion distance in the FeTHBQ crystal but also benefits Li+ transfer between the electrolyte and the electrode. In the FeTHBQ/Graphene nanocomposite, the active material of FeTHBQ manifested multiple redox centers of transition metal ions (Fe3+/Fe2+) and carbonyls (C═O/C-O-) in THBQ ligands. Owing to the enhancements of structural stability, electronic conduction, and Li+ diffusion kinetics, the 2D FeTHBQ/Graphene nanocomposite presented a high lithium-ion storage capacity of 217.2 mA h g-1 at 50 mA g-1, a fast rate capability of 79.1 mA h g-1 at 5000 mA g-1, and a stable cycling performance of 87.2 mA h g-1 at 500 mA g-1 after 100 cycles. This work sheds light on the great opportunity for optimizing the electrochemical performances of CP-based functional electrode materials by combining with conductive substrates.

Conjugated Coordination Nanosheets with Molecular Rotors for Pseudocapacitors: Nanoarchitectonics and Enhanced Performance.

High-level pseudocapacitive materials require incorporations of significant redox regions into conductive and penetrable skeletons to enable the creation of devices capable of delivering high power for extended periods. Coordination nanosheets (CNs) are appealing materials for their high natural electrical conductivities, huge explicit surface regions, and semi-one-layered adjusted pore clusters. Thus, rational design of ligands and topological networks with desired electronic structure is required for the advancement in this field. Herein, we report three novel conjugated CNs (RV-10-M, M=Zn, Ni, and Co), by utilizing the full conjugation of the terpyridine-attached flexible tetraphenylethylene (TPE) units as the molecular rotors at the center. We prepare binder-free transparent nanosheets supported on Ni-foam with outstanding pseudocapacitive properties via a hydrothermal route followed by facile exfoliation. Among three CNs, the high surface area of RV-10-Co facilitates fast transport of ions and electrons and could achieve a high specific capacity of 670.8 C/g (1677 F/g) at 1 A/g current density. Besides, the corresponding flexible RV-10-Co possesses a maximum energy density of 37.26 Wh kg-1 at a power density of 171 W kg-1 and 70 % capacitance retention even after 1000 cycles.

A 3D flexible conductive network skeleton by SWCNT-COOH and PVA-PAA enabling high performance for Si anode

Silicon anode undergoes dramatic volume expansion during charge and discharge, causing structural and interfacial instability that severely degrades battery cycling performance. Herein, we propose a three-dimensional (3D) flexible self-standing SiMP/SWCNT-COOH@PVA/PAA anode, in which carboxylation-modified single-walled carbon nanotubes (SWCNT-COOH) construct a highly conductive and flexible skeleton to provide rapid electron transport channels for micron silicon (SiMP), while polyacrylic acid-polyvinyl alcohol (PVA-PAA) cross-linking layer forms a high-strength polymer interface to strengthen the conductive skeleton and helps to maintain the structural integrity of SiMP. The resulting electrode exhibits ultra-high electrical conductance (12406 S m−1) and exceptional mechanical characteristic (tensile strength of 46.95 MPa). More importantly, it demonstrates extremely stable electrochemical properties, with an impressive maximum capacity of approximately 2868.5 mAh g−1 at 0.2C, while retaining an exceptional 96.49 % of capacity even after 100 cycles. A consistent capacity of 1000 mAh g−1 at 1C throughout 1000 cycles is also realized. Furthermore, a flexible full battery based on SiMP/SWCNT-COOH@PVA/PAA anode achieves a discharge capacity of 49.5 mAh g−1 following 100 cycles, and illuminates a LED strip normally under various bending conditions. These results are expected to open a new way towards enhanced performance silicon-based electrodes within flexible LIBs.

Facile synthesis of high-performance free-standing hierarchically porous NiO/Bi@Bi2O3 hybrid electrode for supercapacitors

By tactfully utilizing the different chemical characteristics of Bi and Ni element in the electrodeposition process, this work successfully designs a novel free-standing NiO/Bi@Bi2O3 hybrid electrode with dual electroactive components (NiO and Bi@Bi2O3) and hierarchically porous structure. After co-electrodeposition, the porous Bi metal as a conductive skeleton can effectively improve the electrical conductivity of the electrode. Moreover, Bi2O3 and NiO have synergistic effects by modifying the electronic structure. The newly developed bimetallic NiO/Bi@Bi2O3 hybrid electrode exhibits high volumetric capacitance value of 1166.67 F cm−3, which is attributed to the dual advantages of structure and composition. This work provides a new idea for the design of high-performance transition metal oxide-based electrodes.

Nitrogen plasma-induced phase engineering and titanium carbide/carbon nanotubes dual conductive skeletons endow molybdenum disulfide with significantly improved lithium storage performance

MoS2/Ti3C2 MXene composite has emerged as a promising anode material for lithium storage due to the synergistic combination of high specific capacity offered by MoS2 and conductive skeleton provided by Ti3C2 MXene. However, its two-dimensional/two-dimensional (2D/2D) structure is susceptible to collapse after long cycles, while the inherent low conductivity of MoS2 limits its rate performance. In this study, we developed a novel approach combining plasma-induced phase engineering with dual skeleton structure design to fabricate a unique P-MoS2/Ti3C2/CNTs anode material featuring highly conductive 1T phase MoS2 and a stable one-dimensional/two-dimensional (1D/2D) architecture. Within this architecture, growth of MoS2 nanosheets on the surface of Ti3C2 cross-linked by carbon nanotubes (CNTs) was achieved. The resulting Ti3C2/CNTs dual skeleton not only provides robust mechanical support to prevent structural collapse during long cycles but also offers increased specific surface area and additional Li+ storage space, thereby enhancing the lithium storage capacity of the composite. Subsequent N2 plasma treatment induced a phase transition in MoS2 from 2H to 1T configuration. Density functional theory (DFT) calculations confirmed that the induced 1T-MoS2 exhibits higher conductivity and lower Li+ diffusion barrier compared to 2H-MoS2. Benefiting from these synergistic effects, our P-MoS2/Ti3C2/CNTs anode demonstrated remarkable electrochemical performance including a high reversible specific capacity of 1120 mAh g−1 at 0.1 A g−1, excellent cycling stability with a specific capacity retention of 670 mAh g−1 after 600 cycles at 1 A/g, and superior rate performance with a specific capacity of 614 mAh g−1 at 2 A g−1. This combined modification strategy will serve as guidance for designing other energy storage materials.

Highly efficient multi-layer flexible heatsink for wearable thermoelectric cooling

Flexible thermoelectric cooler (fTEC), which interfaces well with curved human body surface and provides cooling functions, is an emerging candidate for personal thermal management and non-hospitalized medical treatment. Achieving efficient and long-term cooling performance of TEC requires high thermal conductivity and heat diffusion of the hot side, which has yet to achieve. In this study, we design and fabricate a highly thermally conductive and flexible heatsink with a multi-layered structure especially for wearable TEC wristband, which obtains a large temperature drop (8.8 °C) for imitated on-body test and the maxim 13.1 °C temperature decrease in air. Here, we demonstrate that a well-designed functional composite layer, including phase change material, thermally conductive fillers and metal foam, can establish an effective equilibration among cooling performance, thermal management capacity and mechanical property. Particularly, the heatsink with highly thermal conductive skeleton (k ∼ 2.7 W/mK) and effective heat dissipating fins can significantly improve heat conduction and dissipation, which improve the cooling performance by more than 55 %. With the help of theoretical simulation, we propose a promising strategy for heat management on thermoelectric device through a flexible multi-layered structure, paving the way for achieving practical applications of wearable thermoelectric coolers for personal thermal regulation or cooling therapy.

Highly stable aqueous Zn−I2 batteries enabled by the synergistic adsorption/conversion effect via porous graphitic iodine host

Aqueous zinc-iodide batteries (AZIBs) are considered to be the promising candidate after lithium-ion batteries due to their low cost and high safety. However, the poor electrical conductivity of iodine and the notorious shuttle effect brought about by resolvable polyiodides have seriously hindered the widespread application prospects of AZIBs. In this work, we develop a sample and effective strategy for synthesizing N-doped hierarchical porous graphitized carbon (CN-Mg-CaCO3) that shows great potential as a host material for iodine confinement. The unique porous structure with graphitic domains and synergistic effects of surface adsorption and efficient conversion contribute to the high performance of AZIBs, with notable specific capacity (185 mA h g−1 at 0.1 mA g−1), impressive rate capability (114 mA h g−1 at 10 A g−1), and excellent long-term cycling stability (85 % retention after 104 cycles at 5 A g−1). The elaborately constructed conductive carbon skeleton enhances iodine utilization, while the redox reaction of I2/I- occurs without the formation of intermediates I3-. Additionally, the presence of surface adsorbed Zn2+ leads to enhanced pseudo-capacitance. This research introduces innovative approaches and broadens new ideas for developing cathode materials for AZIBs.

Enhanced Energy Storage Properties and DFT Investigation of a Zn-Co-Mo Heterojunction Rich in Oxygen Vacancies with Dual Electron Transport Pathways.

Petal-like heterojunction materials ZnCo2O4/CoMoO4 with abundant oxygen vacancies are prepared on nickel foam (NF) using modified ionic hybrid thermal calcination technology. Nanoscale ion intermixing between Zn and Mo ions induces oxygen vacancies in the annealing process, thus creating additional electrochemical active sites and enhancing the electrical conductivity. The ZnCo2O4/CoMoO4 conductive network skeleton forms the primary transport pathway for electrons, while the internal electric field of the heterojunction serves as the secondary pathway. ZnCo2O4/CoMoO4 exhibits excellent rate performance and high capacity attributable to its unique double electron transport mode and the effect of oxygen vacancies. The initial discharge capacity at a current of 0.1 A g-1 is approximately 1774 mAh g-1, and the reversible capacity remains at 1100 mAh g-1 after 200 cycles. After a high current of 1 A g-1, the reversible capacity is observed to remain at approximately 1240 mAh g-1. The electronic structure, crystal structure, and work function of the heterojunction interface model are then analyzed by density functional theory (DFT). The analysis results indicate that the charge at the ZnCo2O4/CoMoO4 interface is unevenly distributed, which leads to an enhanced degree of electrochemical reaction. The presence of an internal electric field improves the transport efficiency of the carriers. Experimental and theoretical calculations demonstrate that the ZnCo2O4/CoMoO4 anode material designed in this work provides a reference for fabricating transition metal oxide-based lithium-ion batteries.

Nacre-like Anisotropic Multifunctional Aramid Nanofiber Composites for Electromagnetic Interference Shielding, Thermal Management, and Strain Sensing.

Developing multifunctional flexible composites with high-performance electromagnetic interference (EMI) shielding, thermal management, and sensing capacity is urgently required but challenging for next-generation smart electronic devices. Herein, novel nacre-like aramid nanofibers (ANFs)-based composite films with an anisotropic layered microstructure were prepared via vacuum-assisted filtration and hot-pressing. The formed 3D conductive skeleton enabled fast electron and phonon transport pathways in the composite films. As a result, the composite films showed a high electrical conductivity of 71.53 S/cm and an outstanding thermal conductivity of 6.4 W/m·K when the mass ratio of ANFs to MXene/AgNWs was 10:8. The excellent electrical properties and multi-layered structure endowed the composite films with superior EMI shielding performance and remarkable Joule heating performance, with a surface temperature of 78.3 °C at a voltage of 2.5 V. Additionally, it was found that the composite films also exhibited excellent mechanical properties and outstanding flame resistance. Moreover, the composite films could be further designed as strain sensors, which show great promise in monitoring real-time signals for human motion. These satisfactory results may open up a new opportunity for EMI shielding, thermal management, and sensing applications in wearable electronic devices.

Silicon Carbide Nanowire Based Integrated Electrode for High Temperature Supercapacitors.

Silicon carbide (SiC) single crystals have great prospects for high-temperature energy storage due to their robust structural stability, ultrahigh power output, and superior temperature stability. However, energy density is an essential challenge for SiC-based devices. Herein, a facile two-step strategy is proposed for the large-scale synthesis of a unique architecture of SiC nanowires incorporating MnO2 for enhanced supercapacitors (SCs), arising from the synergy effect between the SiC nanowires as a highly conductive skeleton and the MnO2 with numerous active sites. The SiC@MnO2 integrated electrode-based SCs with ionic liquid (IL) electrolytes were assembled and delivered outstanding energy and power density, as well as a great lifespan at 150 °C. This impressive work offers a novel avenue for the practical application of SiC-based electrochemical energy storage devices with high energy density under high temperatures.

Size Confinement Strategy Effect Enables Advanced Aqueous Zinc–Iodine Batteries

AbstractAqueous Zn–I2 batteries have considerable potential owing to their environmental friendliness and high safety. However, the slow iodine conversion kinetics and shuttle effect prevent their practical applicability. In this study, a series of Zn‐MOF‐74 rods with controllable diameters of 40–500 nm are facilely prepared, denoted as P1–P5. A size confinement strategy effect of Zn‐MOF‐74 derived porous carbon as iodine hosts is proposed to suppress the formation of undesirable iodine species, such as I3− and I5−. Moreover, the graphitization degree of porous carbon samples, including P2‐900, P2‐1000, and P2‐1100, play a critical effect on the iodine conversion kinetics. The P2‐1000 sample possesses a high conductive skeleton and abundant mesopores, which improve the adsorption ability toward iodine species. The electrochemical tests and the in situ technology reveal the size confinement strategy effect and the conversion mechanism of iodine. As a result, the I2@P2‐1000 cathode exhibits a superior discharge capacity of 179.9 mA h g−1 at 100 mA g−1 and exceptional long‐term cycle ability after 5000 cycles. Furthermore, the soft batteries and the flexible quasi‐solid‐state batteries are capable of powering devices, promising to exhibit tremendous adaptability and realize flexible electronic devices in various scenarios.

One-Pot Hydrothermal-Derived rGO/MXene/Sulfur Composite Aerogels as Free-Standing Cathodes in Lithium-Sulfur Batteries.

The confinement and high utilization of sulfur in the cathodes is critical for improved cycling performance of lithium-sulfur batteries. In this case one-pot hydrothermal strategy is developed to produce rGO/MXene/sulfur composite aerogels where sulfur is in situ trapped in the 3D rGO/MXene conductive skeleton. The optimized composite aerogels as free-standing cathodes delivery a specific capacity of 951 mAhg-1 after 100 cycles at 0.2 C with a low fading rate of 0.062 % per cycle. The excellent cycling performance is correlated with highly oxidized MXene and in situ formed sulfate/thiosulfate complex layer in the long-term cycles.

A Hybrid Structure to Improve Electrochemical Performance of SiO Anode Materials in Lithium-Ion Battery.

The wide utilization of lithium-ion batteries (LIBs) prompts extensive research on the anode materials with large capacity and excellent stability. Despite the attractive electrochemical properties of pure Si anodes outperforming other Si-based materials, its unsafety caused by huge volumetric expansion is commonly admitted. Silicon monoxide (SiO) anode is advantageous in mild volume fluctuation, and would be a proper alternative if the low initial columbic efficiency and conductivity can be ameliorated. Herein, a hybrid structure composed of active material SiO particles and carbon nanofibers (SiO/CNFs) is proposed as a solution. CNFs, through electrospun processes, serve as a conductive skeleton for SiO nanoparticles and enable SiO nanoparticles to be uniformly embedded in. As a result, the SiO/CNF electrochemical performance reaches a peak at 20% the mass ratio of SiO, where the retention rate reaches 73.9% after 400 cycles at a current density of 100 mA g-1, and the discharge capacity after stabilization and 100 cycles are 1.47 and 1.84 times higher than that of pure SiO, respectively. A fast lithium-ion transport rate during cycling is also demonstrated as the corresponding diffusion coefficient of the SiO/CNF reaches ~8 × 10-15 cm2 s-1. This SiO/CNF hybrid structure provides a flexible and cost-effective solution for LIBs and sheds light on alternative anode choices for industrial battery assembly.

Polybenzoxazine‐based PEMFC composite bipolar plates with three‐dimensional conductive skeleton

AbstractTo address the limitation of poor conductivity in composite bipolar plates (CBPs), a three‐dimensional (3D) conductive skeleton structure of graphite flakes (GF) is constructed using the sacrificial template method. This method prepares 3D polybenzoxazine/graphite flakes composite bipolar plates (3D‐PBA/GF CBPs) with high conductivity through vacuum impregnation of benzoxazine resin (BA). In this paper, the effect of the presence of a conductive network structure on the key properties of CBPs is analyzed, and the performance of GF randomly dispersed CBPs obtained through traditional solution dispersion is also compared. Thanks to the efficient conductive path within its 3D conductive skeleton structure, the 3D‐PBA/GF CBP achieves excellent conductivity meeting US Department of Energy (DOE) targets (in‐plane conductivity greater than 100 S/cm, area‐specific resistance less than 10 mΩ cm2) at a low filler content (50 wt%). In addition, CBPs with 3D conductive skeleton structures also exhibit qualified service performances to meet the requirements of proton exchange membrane fuel cells (PEMFCs). Compared with GF randomly dispersed CBPs, 3D‐PBA/GF CBPs exhibited higher power density in a single cell. This study demonstrates that constructing PBA/GF CBPs with a 3D conductive skeleton to achieve an accumulation distribution of conductive fillers is an efficient method for enhancing the conductivity of CBPs.

In-situ electrochemical conversion of V2O3@C into Zn3(OH)2V2O7·2H2O@C for high-performance aqueous Zn-ion batteries

Open-framework crystal structured vanadates have been extensively investigated as cathode materials for aqueous zinc-ion batteries (ZIBs). However, the inherent challenges of poor electronic conductivity and structural instability compromise the rate capability and overall cycle life. Herein, we first successfully synthesized octahedral MIL-101(V) and prepared the Zn3(OH)2V2O7·2H2O@C (ZVOH@C) composite by in-situ electrochemical conversion of MIL-101(V)-derived crystalline V2O3 and carbon composite (V2O3@C). The ZVOH@C composite of open-framework crystal structured Zn3(OH)2V2O7·2H2O and conductive carbon skeleton not only possesses more active sites, more stable crystal structure and higher electrical conductivity, but also provides faster Zn2+ diffusion kinetics. As expected, the ZVOH@C composite electrode exhibits excellent capacity of 506.3 mAh/g at a current density of 1.0 A/g, exceptional rate performance (375.7 mAh/g at 20.0 A/g), and impressive long-term cycling stability, maintaining 314.5 mAh/g over 5000 cycles at 20.0 A/g. This study demonstrates a promising method for designing new cathode materials through in-situ electrochemical synthesis for ZIBs.