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[Display omitted] • Constructed Co@CoO core–shell crosslinked frameworks on 3D Cu. • The crosslinked framework demonstrates the ability to hinder dendritic growth. • Co@CoO supplies abundant lithium-affinitive sites. • Co@CoO helps to build the Li 2 O-rich SEI. • The symmetric cells can stably cycle for 1400 h at 1 mA cm−2 and 1 mAh cm−2. Lithium metal anode with high energy density is important for developing next-generation batteries. However, low coulombic efficiency, short cycle life, internal short circuits caused by the growth of lithium dendrites, and the high reactivity with the electrolyte have seriously hindered the practical application of lithium metal anode. Herein, we constructed a core–shell cross-link matrix on copper, Co@CoO/3D Cu, for Li metal anode optimization. Various characterizations and DFT simulations jointly reveal the great effects of the special structural features of Co@CoO/3D Cu on enhancing the coulombic efficiency and cyclic stability of Li metal anodes. As a result, the modified half-cell could cycle stably for 240 cycles at 1 mA cm−2 and 1 mA h cm−2 with a coulombic efficiency as high as 98 %. The modified symmetric cell could cycle stably for 1400 h at 1 mA cm−2 and 1 mA h cm−2 with a very low polarization of 22 mV. The modification method proposed in this paper provides a novel path for Li metal anode optimizations. [ABSTRACT FROM AUTHOR]

Constructing artificial solid electrolyte interface on the Zn anode surface is recognized as an appealing method to inhibit zinc dendrites and side reactions, whereas the current techniques are complex and time‐consuming. Here, a robust and zincophilic zinc tungstate (ZnWO4) layer has been in situ constructed on the Zn anode surface (denoted as ZWO@Zn) by an ultrafast chemical solution reaction. Comprehensive characterizations and theoretical calculations demonstrate that the ZWO layer can effectively modulate the interfacial electric field distribution and promote the Zn2+ uniform diffusion, thus facilitating the uniform Zn2+ nucleation and suppressing zinc dendrites. Besides, ZWO layer can prevent direct contact between the Zn/water and increase the hydrogen evolution reaction overpotential to eliminate side reactions. Consequently, the in situ constructed ZWO layer facilitates remarkable reversibility in the ZWO@Zn||Ti battery, achieving an impressive Coulombic efficiency of 99.36 % under 1.0 mA cm−2, unprecedented cycling lifespan exceeding 1800 h under 1.0 mA cm−2 in ZWO@Zn||ZWO@Zn battery, and a steady and reliable operation of the overall ZWO@Zn||VS2 battery. The work provides a simple, low cost, and ultrafast pathway to crafting protective layers for driving advancements in aqueous zinc‐metal batteries. [ABSTRACT FROM AUTHOR]

Hard carbon with randomly oriented interlayers is the most promising candidate for the anode of commercial sodium‐ion batteries (SIBs). Nevertheless, its sluggish sodium storage kinetics and unsatisfactory cycling stability are bottlenecks to its implementation. Herein, a metal‐single atom modification strategy is proposed to construct a Ni‐single atoms modified N, P co‐doped hard carbon (Ni‐NPC) with a Ni content of ≈5.65 wt%. As an anode for SIBs, Ni‐NPC exhibits far superior initial Coulombic efficiency, reversible specific capacity, rate capability, and cycling stability to N, P co‐doped hard carbon. Combining in situ EIS and ex‐situ XPS,this study reveals that Ni‐single atoms modulate the composition of the solid electrolyte interface layer, thereby improving the cycling stability of Ni‐NPC. Theoretical calculation and kinetics analysis suggest that Ni‐single atoms are the promoters of the diffusion of Na+. Furthermore, with the aid of systematic in situ characterizations, the structural evolution of Ni‐NPC at different sodium storage stages is identified. This work proposes a potential strategy for simultaneously improving the sodium storage kinetics and cycling stability of hard carbon anodes, and elucidates the improvement mechanism of this strategy. [ABSTRACT FROM AUTHOR]

Herein, potato starch residue derived carbon materials (PSRC) and KOH activated PSRC (denoted as APSRC) are successfully realized in this work. Interestingly, it is found that PSRC shows better electrochemical performance in potassium ion batteries (KIBs) than in sodium ion batteries (NIBs); however, the APSRC exhibits more excellent performance in NIBs than in KIBs. It is worth noting that the surface area and pore volume might be essential to Na+/K+ storage. For the PSRC with relatively lowered surface area and pore volome, the diffusion-controlled process is the main storage mode in NIBs. Nevertheless, the surface charge storage process is the main storage way for the PSRC in KIBs. On the other hand, the APSRC possesses large ratio of surface-dominated contribution to the whole capacity in NIBs and KIBs, which could be attributed to the more active sizes because of the larger surface area and higher pore volume. Furthermore, based on the optimal performance of APSRC in SIBs, sodium ion capacitors (NICs) utilizing APSRC as both cathode and anode materials are assembled. This NICs demonstrate satisfied performance with the energy density of 76.4 Wh kg−1 at the power density of 150 W kg−1. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (ZIBs) hold significant promise in the future energy storage market. However, the uncontrolled growth of zinc dendrites and the occurrence of side reactions severely constrain the practical deployment of ZIBs. To address these challenges, this study suggests incorporating H3BO3 (HBO) as an electrolyte additive into the ZnSO4 electrolyte, with the aim of inducing preferential growth of the (002) plane. HBO molecules selectively adsorb onto the (100) and (101) planes of zinc, promoting the deposition of Zn2+ ions into the (002) plane and resulting in the formation of a uniformly deposited layer while concurrently inhibiting side reactions. The results demonstrate that ZnǁZn symmetric batteries, with the HBO additive, exhibit stable cycling at high current density, achieving a cycling life of 1100 h at 10 and 10 mAh cm−2 as well as 250 h at 50% depth of discharge. Furthermore, the ZnǁVO2 coin cell demonstrates stable cycling for 1700 cycles at 1 A g−1 and 7000 cycles at 5 A g−1. This study presents a promising case for the commercialization of advanced ZIBs. [ABSTRACT FROM AUTHOR]

• Li 3 P protective layer induces uniform deposition of Li+ ions. • Li 3 P protective layer homogenizes the charge distribution on the electrode. • Li 3 P protective layer observably reduces side reactions with the electrolyte. • Li 3 P@Li electrode exhibits excellent capacity retention rate and cycling stability. To suppress dendrites and avoid side reactions that hinder the practical application of Li metal anode, a homogeneous lithiophilic Li 3 P layer is cast on the Li metal anode surface (Li 3 P@Li) via a simple impregnation process. The low Li+ diffusion barrier of the obtained Li 3 P layer facilitates the dendrite-free Li deposition. A prolonged cycle life of 2740 h with low overpotential (∼10 mV) is thus achieved by the Li 3 P@Li electrode. The cycle performance of Li 3 P@Li || LiFePO 4 full cell is also improved, which remains an 85 % capacity retention after 1200 cycles at 3C. This work provides new ideas for Li metal anode surface engineering and promotes Li metal anode's practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

The long‐term reversible plating/stripping of Zn metal anode is a critical aspect within aqueous zinc‐ion batteries (ZIBs). However, it is limited by uncontrolled electrodeposition and side reactions occurring at the anode/electrolyte interface. Guided by the metal‐coordination chemistry, a novel additive, sodium diphenylamine sulfonate (DASS), is added into ZnSO4 electrolyte to guide stably invertible zinc deposition. Theoretical calculations and experimental results reveal that the DASS can adsorbed on the Zn anode surface due to the strong double coordination effect between N, S sites and Zn (Zn─N, Zn─S), and this adsorbed DASS layer can not only prevent the intimate contact between H2O and anode to inhibit interfacial side reactions, but also guide the 3D Zn2+ion diffusion and uniform electrodeposition to inhibit zinc dendrites. Consequently, the DASS additive enables an ultra‐long stable cycling up to 2400 h at 1 mA cm−2 (1 mAh cm−2), even at an ultra‐high current density of 20 mA cm−2, a stable cycling of 250 h is demonstrated, highlighting the reliable coordination effect at the anode/electrolyte interface. This study offers a new perspective on the interfacial double‐coordination effect for achieving highly reversible Zn metal anodes in aqueous rechargeable zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

PLF pretective layer provides a high Young's modulus, which effectively inhibits the growth of Li dendrites, guarantees a low Li diffusion energy barrier, which makes Li+ transfer quickly and leads to uniform deposition of Li+. [Display omitted] • PLF protective layer induces uniform deposition of Li+ ions. • PLF protective layer significantly reduces the surface local current density. • PLF protective layer effectively reduces side reactions with the electrolyte. • PLF-modified electrode exhibits excellent rate capability and cycling stability. Lithium (Li), with superior specific capacity and lowest standards electrode potential, has been touted as the "Holy Grail" among various anode materials. However, in the process of repeated lithium plating/stripping, the uncontrollable lithium dendrite growth and unstable interface inevitably affect the application of lithium metal batteries. Here, an ingeniously designed artificial protective layer consisting of polyvinyl alcohol polymer and lithium fluoride was coated on a Cu current collector to overcome the obstacles above. High Young's modulus and favourable ionic conductivity are ensured through the synergistic interaction between soft and rigid structural elements evenly distributed in the layer. Dense Li deposition with no dendrite, conspicuously reduced interfacial resistance, and dramatically prolonged cycle life were achieved, ascribing to the interface stabilization by the artificial protective layer. This work shed light on the artificial protective layer design strategy and the energetic chemistry and mechanics of anodes in working batteries. [ABSTRACT FROM AUTHOR]

Zn 3 Hg alloy can effectively suppress the dendrites growth and corrosion reaction through instantaneous alloying reaction during the plating process, ensuring extremely low voltage hysteresis, excellent cycling performance and rate capability. [Display omitted] • Zn 3 Hg anode exhibits the extremely low voltage hysteresis of 8 mV. • Zn 3 Hg electrode displays excellent rate capability and cycling stability. • The plated Zn instantly form Zn-Hg alloy through alloying reaction. • Zn 3 Hg electrode effectively suppress the dendrites growth and corrosion reaction. Zinc metal anode has serious dendrites and corrosion issues in the mild electrolyte, which greatly hinder the commercialization of aqueous zinc-ion batteries. Herein, zinc-amalgam (Zn 3 Hg) alloy anode has been prepared and displays a unique synergistic zinc plating/stripping and alloying/dealloying reaction mechanism. The ultrafast zinc ions diffusion in Zn 3 Hg and the alloying reaction of Zn 3 Hg with Zn ions effectively suppress the dendrites growth and skillfully address corrosion issues. Consequently, the Zn 3 Hg anode expresses long cycle life of 2000 h at 1 mA cm−2/1 mAh cm−2 and exhibits the lowest voltage hysteresis of only 8.0 mV that we know so far. Even at 5 mA cm−2/5 mAh cm−2 and 10 mA cm−2/10 mAh cm−2, the Zn 3 Hg anode also exhibits excellent cycling stability and low voltage hysteresis. Moreover, zinc ion capacitors composed of Zn 3 Hg anode and active carbon cathode still possess a specific capacity of 61 mAh/g after 5000 cycles at 1 A/g. The Zn 3 Hg anode enriches the varieties of zinc alloy anodes and provides a new development path for constructing stable and dendrite-free zinc metal anodes. [ABSTRACT FROM AUTHOR]

ZnSe is considered to be an intriguing anode material arising from its high theoretical capacity and low cost in potassium ion batteries (PIBs). The poor reaction kinetics and unfavorable structural stability, however, largely impede the performance. Herein, a dual carbon manipulated yolk-shell ZnSe microsphere (ZnSe-C@NC) is rationally envisaged, with ideal construction stability and efficient K+ diffusion process. A high discharge capacity of 549.9 mAh g−1 with favorable initial Coulombic efficiency of 81.8% can be achieved at 100 mA g−1. Even at the current density of 1000 mA g−1, the reversible capacity is as high as 456.4 mAh g−1. Concurrently, a full PIB based on ZnSe-C@NC is designed with a high energy density of 133.8 Wh kg−1 at the power density of 236 W kg−1. The experiment and in-depth density functional theory (DFT) calculation results demonstrate that the N doped carbon decoration on ZnSe would greatly accelerate charge transportation, narrow the bandgap and minimize K+ movement energy barrier. On the other hand, the dual carbon protection endow that the unique yolk-shell construction with superb mechanical stability during long circulation, bringing about exceptional electrochemical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

The high-efficient, controllable, and non-destructive chemical prelithiation of VO 2 (B) electrodes have been successfully accomplished via a Li-BP derivative/THF reagent, gaining a high-energy and long-life Li-ion battery. [Display omitted] • A non-destructive chemical prelithiation of VO 2 (B) anodes was achieved using a reductive Li-arene reagent. • The prelithiated VO 2 (B) anode exhibited an initial Coulombic efficiency of nearly 100 %. • The SEI layer formed on the prelithiated VO 2 (B) electrode contained a variety of favorable functions. • The Prelithiation VO 2 (B)||NCM811 full cell realized a rise in the energy density of at least 20 %. VO 2 (B) stands as a promising anode material, comparable to the disordered rock-salt phase Li 3+x V 2 O 5 , owning to its ease of preparation, suitable redox potential, and remarkable rate capability. However, the practical application of VO 2 (B) anodes faces substantial limitations due to its low initial coulombic efficiency (ICE) and instability of solid electrolyte interface (SEI) layer during cycling. In this study, we introduce a highly efficient, controllable, and non-destructive chemical prelithiation method utilizing a reductive Li-arene reagent, formed by dissolving Li-metal to THF solutions containing biphenyl derivatives. This method enables the VO 2 (B) anode to achieve an ICE of nearly 100 %. The investigation on the chemical composition and mechanical properties of SEI layers reveals that the prelithiated VO 2 (B) electrode contains a more favorable LiF component, fewer adverse byproducts, and exhibits a thinner thickness with high structural strength. Kinetic analysis demonstrates that the prelithiation treatment accelerates the diffusion of lithium ions, reduces interfacial reaction resistances, and maintains interface stability during cycling. To demonstrate the practical application, we assemble a well-designed Prelithiation VO 2 (B)||NCM811 full cell, achieving an enhancement in the energy density of at least 20 %. This work underscores the potential of prelithiated VO 2 (B) electrodes for developing lithium-ion batteries (LIBs) with high-safety and high-energy/power density. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-supported Fe-Ni-P nanosheet arrays are obtained as anode for PIBs. • A capacity of 201.7 mAh g−1 for Fe-Ni-P electrode at 0.5 A g−1 after 200 cycles. • The nanosheet arrays construction can s release the mechanical strain. • The volume expansion can be alleviated by the synergistic effect of Fe 2 P and Ni 2 P. Transition metal phosphates (TMPs) are considered as promising anode materials for sodium-ion batteries (SIBs) due to their high theoretical capacity (up to 1000 mAh g−1) and low cost. However, the poor electrochemical reaction kinetics and large volume expansion of TMPs are not conducive to practical applications in SIBs. In view of this, a kind of self-supported iron nickel phosphide (Fe-Ni-P) composite nanosheet arrays are obtained by reasonable hydrothermal reaction and phosphidation process. The nanosheet arrays construction can significantly release the mechanical strain and promote electrochemical reaction kinetics. Furthermore, the volume expansion can be largely alleviated by the synergistic effect of Fe 2 P and Ni 2 P. Benefiting from the unique design, the robust Fe-Ni-P arrays manifest remarkable Na+ storage capability. The Fe-Ni-P nanosheet arrays exhibit a large discharge capacity of 300.9 mAh g−1 after 100 cycles at 0.1 A g−1. And there is a reversible capacity of 201.7 mAh g−1 can be maintained without obvious capacity loss after 200 cycles at 0.5 A g−1 in SIBs. [ABSTRACT FROM AUTHOR]

Herein, we successfully deposit V2O5 nanobelt arrays on Ni foam uniformly coated with reduced graphene oxides (rGO), to manufacture V2O5/rGO arrays directly as anode for SIBs. The ordered and open architecture of V2O5/rGO arrays greatly facilitates the transportation of sodium ions and electrons. In particular, the introduction of rGO can substantially advance the whole electronic conductivity of the V2O5/rGO anode, as well as efficaciously prevent the V2O5 arrays exfoliation from the substrate. Consequently, the electrochemical performance of V2O5/rGO arrays can be highly improved compared with bare V2O5 arrays. As expected, the V2O5/rGO arrays anode yields a reversible capacity of 0.62 mAh cm−2 after 100 cycles at 0.4 mA cm−2 in the potential range of 0.01–3 V. It can be predicted that this innovative trial in this article might pave the way for tailoring high performance V2O5-based anode materials. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (ZIBs) hold great promise in electrochemical applications due to their cost-effectiveness and high safety. However, the practical utilization of ZIBs faces challenges from detrimental zinc dendrite formation and side reactions, which adversely impact their cycling lifespan and electrochemical stability. In this research, we proposed a commonly available and cost-effective organic solvent, N, N-dimethylformamide (DMF), as an electrolyte additive to stabilize Zn anode. According to the experimental characterizations and theoretical calculations, DMF exhibits a strong interaction with Zn2+ ions, which can not only regulate the Zn2+ solvation structure to mitigate side reactions, but also promote the uniform deposition of Zn2+ to suppress Zn dendrites. Hence, the symmetrical Zn/Zn cell assembled with a mixed electrolyte of ZnSO 4 and DMF (ZSO+DMF) demonstrated an impressive cycle lifespan of up to 1600 h under a current density of 1 mA cm−2. Moreover, the coulombic efficiency (CE) of Zn/Ti batteries operating at 1 mA cm−2 was significantly improved to 98.36%, surpassing that in ZnSO 4 electrolytes (95.34%). Additionally, the performance of Zn/VO 2 cells further validates the effectiveness of the DMF additive. These findings highlight the potential of DMF as a valuable electrolyte additive to enhance the electrochemical performance and cycling stability of Zn-based batteries, offering a practical and cost-efficient approach to advancing the development of ZIBs. [Display omitted] • A comment used organic solvent has been utilized as electrolyte additive. • DMF shows strong interaction with Zn2+ ions and regulate the Zn2+ solvation sheath. • DMF additive can inhibit the harmful zinc dendrites and side reactions. • DMF additive can boost the electrochemical performance of full zinc-ion batteries. [ABSTRACT FROM AUTHOR]

Using NiSn(OH) 6 cubes as starting templates, hierarchical double-shells NiS/SnS@nitrogen-doped carbon nanoboxes are controllably synthesized for the first time. Benefiting from their sophisticated component and structure, a high-capacity and long-life Na-ion battery can be realized. [Display omitted] • Double-shelled NiS/SnS@N-doped carbon nanoboxes are controllably prepared using NiSn(OH) 6 cube templates. • The obtained anodes exhibit ultra-stability at a high rate while maintaining a large capacity. • The desired anode's reaction kinetics, sodiation mechanism, and potential application are revealed. • Our proposed method can be used to build various hollow ternary-tin-metal sulfides or selenides. Overcoming the sluggish reaction kinetics and volume effects of metal sulfides as anodic materials for sodium-ion batteries remains a challenging task. In this study, a multistep template-engaged strategy is employed for the first time to fabricate hierarchical double-shells NiS/SnS@nitrogen doped carbon (NiS/SnS@NC) nanoboxes, utilizing NiSn(OH) 6 cubes as starting templates. The synergistic combination of sophisticated sulfide components and the double-shell structure effectively mitigates volume variation, reduces nanoparticle cohesion, and enhances electrode reaction kinetics. Notably, NiS/SnS@NC exhibits outstanding stability under high current density while maintaining a high capacity. Comprehensive kinetics analysis reveals that the enhanced sodium storage of NiS/SnS@NC can be attributed to its low interface reaction resistance, significant capacitive contribution, and rapid mass-transfer kinetics. The stepwise (de)sodiation processes of the NiS/SnS@NC anode are elucidated through various in/ex-situ characterization techniques, confirming the alternating reaction activity alternations between two components, which acts as a self-buffering and self-conductivity mechanism to enhance sodium storage. Finally, a practical application is demonstrated, where a well-designed NiS/SnS@NC||Na 3 V 2 (PO 4) 2 F 3 /C full cell shows promising performance, achieving a high capacity of 265 mAh/g after 1000 cycles at 2.0 A/g. This work′s synthesis strategy and research findings contribute to advancing the exploration and application of NiSn(OH) 6 and its derivatives in the field of energy storage and beyond. [ABSTRACT FROM AUTHOR]

NiO/C-Ni composite is prepared via a facile hydrothermal pretreatment and subsequent annealing, which shows excellent cycle stability and superior rate capability as binder free anode for lithium ion batteries. It delivers initial discharge and charge capacity of 971 and 672 mAh g −1 at 0.3C, maintaining of 700 and 669 mAh g −1 after 70 cycles. After 60 cycles at various rates from 0.3 to 12C, the discharge capacity of the NiO/C-Ni electrode can gradually restore when reverting the rate to 0.3C, maintaining of 692 mAh g −1 after 10 cycles. The impressive electrochemical performance demonstrates great potential of the NiO/C-Ni as anode for high performance lithium ion batteries. [ABSTRACT FROM AUTHOR]

High capacity and superlong cycle life of Li 3 VO 4 have been actualized via carbon hybridization and N doping. The Li 3 VO 4 /N doped C (Li 3 VO 4 /N–C) that fabricated via an in situ carbonization method based on an intermedial solution phase delivers initial discharge and charge capacities of 686 and 540 mAh g −1 at a specific current of 0.15 A g −1 , which maintain of 538 and 536 mAh g −1 after 800 cycles, showing excellent cycle stability. Meanwhile, the Li 3 VO 4 /N–C exhibits superior rate performance and long life performance. After 150 cycles at various specific currents from 0.1 to 2.0 A g −1 , the discharge and charge capacities can restore 100% when reverting the specific current to 0.1 A g −1 . After 1100 cycles at a specific current of 2.0 A g −1 , the discharge and charge capacities can maintain of 340 and 337 mAh g −1 , showing no capacity attenuation in cycling. [ABSTRACT FROM AUTHOR]

NiCr 2 O 4 is successfully prepared via hydrothermal pretreatment and subsequent sintering, which shows excellent electrochemical performance as a new anode material for lithium ion batteries with natural graphite adding and sodium alginate binder. At a specific current of 70 mA g −1 , it delivers charge and discharge capacities of 465.5 and 919.8 mAh g −1 in the initial cycle, which gradually increases along with cycle number owing to an electrochemical reconstruction in cycling. After 100 cycles, the charge and discharge capacities are 582.9 and 592.5 mAh g −1 , respectively. Furthermore, it is testified that natural graphite adding can effectively improve the electronic conductivity of the NiCr 2 O 4 electrode, and an appropriate amount of natural graphite is beneficial to improve the specific capacity and cycle stability of the electrode owing to a coordinated electrochemical reconstruction between NiCr 2 O 4 and natural graphite in cycling. [ABSTRACT FROM AUTHOR]

CoV 2 O 6 /natural graphite electrode with sodium alginate binder is prepared, which shows excellent electrochemical performance as anode for Li-ion batteries. It exhibits initial discharge and charge capacity of 902 and 638 mAh g −1 at a specific current of 110 mA g −1 . After 100 cycles, the discharge and charge capacity maintain of 669 and 665 mAh g −1 , respectively. The charge/discharge mechanism of CoV 2 O 6 is also studied, suggesting a structure variation in discharging, which involves the initial formation of LiV 2 O 5 and Co 3 V 2 O 8 , the subsequent transition from Co 3 V 2 O 8 to Li x V 2 O 5 and CoO, and the later reduction of CoO into Co. The structure variation of Co 3 V 2 O 8 accompanies by an amorphization process, which maintains in the subsequent discharging and charging process. [ABSTRACT FROM AUTHOR]

Highlights: [•] We prepared Cu2O–Cu composite architecture via an electrochemical corrosion method. [•] We explored the utilization of electrochemical corrosion of metal in Li-ion batteries. [•] The obtained Cu2O–Cu electrode shows excellent cycle stability and rate capability. [•] The effect of corrosion condition on electrochemical performance of Cu2O–Cu was studied. [ABSTRACT FROM AUTHOR]

A novel in situ electrochemical reconstruction occurs in NiV3O8/natural graphite electrodes, which results in excellent electrochemical performance. After repeated rate performance from 0.16 to 3.1 A g−1 over 320 cycles, the specific capacity can restore well and shows no obvious attenuation in the subsequent 360 cycles. [ABSTRACT FROM AUTHOR]

In light of the sluggish potassiation kinetics in potassium ion batteries, herein, we report a self-supported anode material composed of CuO/Cu clusters distributed in nitrogen-doped carbon microfibers (CuO/Cu-NCNFs electrode) via a simple electrospinning technology. By this way, a three-dimensional conductive networks interwoven by CuO/Cu-NCNFs microfibers were successfully obtained. As expected, this self-supported anode materials for potassium ion batteries reveals better electrochemical performance compared with nitrogen-doped carbon microfibers (NCNFs). There is still a reversible capacity of 205.9 mAh g−1 remained for the CuO/Cu-NCNFs electrode undergoing 100 cycles at 100 mA g−1. With the in-depth investigation, the CuO/Cu-NCNFs show more obvious pseudocapacitive characteristic than that of NCNFs. The improved capacitive contribution discloses the reason for the fast kinetics of CuO/Cu-NCNFs. It is believed that the presence of CuO/Cu significantly favors the advancement of mechanical property and stability of microfiber networks, giving rise to the fast kinetics of CuO/Cu-NCNFs. It can be predicted that this innovative potocol of CuO/Cu-NCNFs microfiber frameworks will provide explicit direction toward engineering high performance electrode materials for potassium ion batteries. Unlabelled Image • Self-supported CuO/Cu-NCNFs microfibers have been obtained as anode for PIBs. • CuO/Cu-NCNFs show more excellent performance than NCNFs. • CuO/Cu clusters result in satisfied mechanical property and performance. • Capacity of 205.9 mAh g−1 is remained for CuO/Cu-NCNFs after 100 cycles. [ABSTRACT FROM AUTHOR]