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Rechargeable Zn‐based batteries provide a compelling supplement to subsistent energy storage devices owing to their high energy density, good safety, and low cost. Nevertheless, inherent imperfections such as dendrite growth, side reactions, and andante reaction kinetics, severely impede their commercialization. As new 0D nanomaterials, carbon dots (CDs) with unique characteristics and excellent electrochemical activity, exhibit promising potential exploitation in electrochemistry and electrocatalysis areas. Herein, the adhibition of CDs in resolving the aforementioned drawbacks of Zn‐based batteries is introduced. To begin with, concepts, physicochemical properties, and synthetic methods of CDs are discussed. Next, recent developments and advances exploiting CDs in respectively ameliorating the performance of the Zn anode, the cathode, and electrolytes of Zn ion batteries and bifunctional electrocatalytic activities including oxygen reduction reaction and oxygen evolution reaction for Zn‐air batteries, are roundly reviewed and minutely generalized. Finally, current challenges and prospects are surveyed as well, aiming to offer a reference for the blossom of advanced Zn‐based batteries. [ABSTRACT FROM AUTHOR]

Zinc‐ion batteries (ZIBs) have become a global research hotspot in recent years due to their eco‐friendliness, safety, abundant resources, and low cost. However, some significant challenges seriously affect their overall performance, thus hindering their further development and practical applications. Recently, multifunctional and adjustable 2D carbides and nitrides (MXenes) are extensively used for the modification of ZIBs, and fruitful achievements are achieved. In order to make a systematic understanding of these studies, it is highly desirable to provide an overview of MXenes based on their modification methods and action mechanisms. In this review, a basic introduction to ZIBs and MXenes is presented and the main modification approaches of MXenes in solving the issues of ZIBs are discussed in detail, including activation and composite strategies of the cathode, interface engineering, structural optimization, and zinc metal‐free anode strategy of the anode, solid‐state strategy of the electrolyte, and functionalized strategy of the separator. Importantly, the functions and related mechanisms of MXenes in various components of ZIBs are analyzed in depth. Finally, the pathways for MXenes in solving the issues of ZIBs are summarized, and their future directions are prospected. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable batteries (ARBs) have attracted wide attention due to their rich resources, environmental friendliness, and safety. The high ionic conductivity, safety and interfacial wettability of the aqueous electrolyte are essential for energy storage devices. However, the narrow electrochemical stability window (ESW) of the aqueous electrolyte and the side reactions of the electrode/electrolyte lead to the low energy density of the ARBs. In the past studies, the above problems were generally solved by improving the ion transport characteristics of the electrolyte and the electrode/electrolyte interface. Herein, we discuss the background, limitations, and key concepts for performance improvement of aqueous electrolytes, aiming to provide a comprehensive perspective and inspiration for further research on aqueous electrolytes and promote their development and application in the field of energy storage. [ABSTRACT FROM AUTHOR]

The utilization rate of active sites in cathode materials for Zn‐based batteries is a key factor determining the reversible capacities. However, a long‐neglected issue of the strong electrostatic repulsions among divalent Zn2+ in hosts inevitably causes the squander of some active sites (i.e. gap sites). Herein, we address this conundrum by unraveling the "gap‐filling" mechanism of multiple charge carriers in aqueous Zn‐MoS2 batteries. The tailored MoS2/(reduced graphene quantum dots) hybrid features an ultra‐large interlayer spacing (2.34 nm), superior electrical conductivity/hydrophilicity, and robust layered structure, demonstrating highly reversible NH4+/Zn2+/H+ co‐insertion/extraction chemistry in the 1 M ZnSO4+0.5 M (NH4)2SO4 aqueous electrolyte. The NH4+ and H+ ions can act as gap fillers to fully utilize the active sites and screen electrostatic interactions to accelerate the Zn2+ diffusion. Thus, unprecedentedly high rate capability (439.5 and 104.3 mAh g−1 at 0.1 and 30 A g−1, respectively) and ultra‐long cycling life (8000 cycles) are achieved. [ABSTRACT FROM AUTHOR]

Highlights: Oxygen-respirable sponge was constructed by carbon dots-assisted synthesis strategy. The hydrophilicity and aerophilicity of Co@C–O–Cs active sites boost oxygen diffusion and the bifunctional oxygen reduction reaction and oxygen evolution reaction activities. Co@C–O–Cs-based Zn-air battery (ZAB) displays excellent specific capacity and stability, and the all-solid-state Co@C–O–Cs-based ZAB exhibits excellent flexibility. Efficient bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are vital for rechargeable Zn-air batteries (ZABs). Herein, an oxygen-respirable sponge-like Co@C–O–Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy. The aerophilic triphase interface of Co@C–O–Cs cathode efficiently boosts oxygen diffusion and transfer. The theoretical calculations and experimental studies revealed that the Co–C–COC active sites can redistribute the local charge density and lower the reaction energy barrier. The Co@C–O–Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm−2 for OER. Moreover, it can drive the liquid ZABs with high peak power density (106.4 mW cm−2), specific capacity (720.7 mAh g−1), outstanding long-term cycle stability (over 750 cycles at 10 mA cm−2), and exhibits excellent feasibility in flexible all-solid-state ZABs. These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries. [ABSTRACT FROM AUTHOR]

The rational design of bifunctional catalysts with excellent activity and stability toward the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is essential for rechargeable Zn‐air batteries (ZABs). In this study, a facile coordination bridging strategy is proposed to construct bifunctional Co‐CoN4 hybrid active sites embedded in porous N‐rich carbon nanolamellas (denoted as Co‐CoN4@NCNs) for both the ORR and OER. Synchrotron X‐ray absorption spectroscopy and density functional theory calculations reveal that the increased intrinsic ORR/OER activities can be attributed to the efficient interfacial charge transfer between the atomic CoN sites and metallic Co sites due to their robust electronic correlation. In situ Raman spectroscopy confirms that the OER activity depends on the CoOOH intermediates formed during the reaction. Co‐CoN4@NCNs exhibits superior bifunctional catalytic performance for the ORR (E1/2 = 0.83 V) and OER (η = 310 mV at 10 mA cm−2) conducted in alkaline media. The assembled rechargeable Co‐CoN4@NCNs‐based ZAB displays an open‐circuit voltage of 1.47 V, peak power density of 118.8 mW cm−2, specific capacity of 776.7 mAh g−1, and outstanding cycling stability over 1500 cycles. The regulation of the interfacial electronic properties can contribute to the rational design of bifunctional electrocatalysts used in rechargeable metal‐air batteries. [ABSTRACT FROM AUTHOR]

The development of low‐cost multifunctional electrocatalysts with high activity for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) is critical for the advancement of sophisticated energy conversion and storage devices. Herein, a trifunctional Ni(S0.51Se0.49)2@NC catalyst is designed and fabricated using a dianionic regulation strategy. Synchrotron radiation X‐ray absorption spectroscopy and density functional theory calculations reveal that simultaneous sulfidation and selenization can induce the electronic delocalization of Ni(S0.51Se0.49)2 active sites to enhance the adsorption of *OOH/*OH intermediate for ORR/OER and H* intermediate for HER. The OER and HER mechanisms are revealed by in situ Raman spectroscopy. The Ni(S0.51Se0.49)2@NC exhibits trifunctional catalytic activity for the HER (111 mV at 10 mA cm−2), OER (320 mV at 10 mA cm−2), and ORR (half‐wave potential of 0.83 V). The rechargeable zinc–air batteries (ZABs) exhibit an open‐circuit voltage of 1.46 V, a specific capacity of 799.1 mAh g−1, and excellent stability for 1000 cycles. The water electrolytic cell using Ni(S0.51Se0.49)2@NC electrodes delivers a current density of 10 mA cm−2 at a cell voltage of 1.59 V, and it can be powered using the constructed ZABs. These findings contribute to developing low‐cost and efficient non‐noble metal multifunctional catalysts. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) have appealed increasing attention due to the inexpensive K‐element resources and satisfactory electrochemical properties. Presently, there are still challenges for developing desirable anode materials. Two‐dimensional metal sulfides exhibit high specific capacity as host for PIBs, yet the dissolution and agglomeration of unstable reaction intermediate KxSy (K2S, K2S5) inescapability induces large loss of active ingredients and poor reactions reversibility, leading to inferior lifespan. Herein, polar polysulfide VS4 is introduced into SnS nanosheets with constructing layered VS4/SnS heterostructure anchored in graphene scaffold (VS4/SnS@C). In this framework, VS4 with unsaturated bridging (S2)2– can act as the anchoring sites to stabilize intermediates KxSy with efficient entrapment effects. Moreover, the heterostructure can maintain layered SnS and regulate the distribution of KxSy with high conversion reversibility. The reaction reversibility and intermediate absorptivity are enhanced, as confirmed by in situ X‐ray diffraction analysis and theoretical calculations. Consequently, the VS4/SnS@C electrode exhibits ultra‐long lifespans, which achieves a capacity of 168.4 mAh g–1 at 1 A g–1 after 6000 cycles. This strategy of heterostructure design facilitates the understanding of K‐storage mechanisms and significantly enhances the reaction reversibility, providing a thought to address the challenges in metal sulfide anodes toward the development of high‐performance PIBs. [ABSTRACT FROM AUTHOR]

The use of a sacrificial cathode additive as a pre‐metallation method could ensure adequate metal sources for advanced energy storage devices. However, this pre‐metallation technique suffers from the precise regulation of decomposition potential of additive. Herein, a molecularly compensated pre‐metallation (Li/Na/K) strategy has been achieved through Kolbe electrolysis, in which the electrochemical oxidation potential of a metal carboxylate is manipulated by the bonding energy of the oxygen–metal (O–M) moiety. The electron‐donating effect of the substituent and the low charge density of the cation can dramatically weaken the O–M bond strength, further bringing out the reduced potential. Thus, sodium acetate exhibits a superior pre‐sodiation feature for sodium‐ion battery accompanied with a large irreversible specific capacity of 301.8 mAh g−1, remarkably delivering 70.6 % enhanced capacity retention in comparison to the additive‐free system after 100 cycles. This methodology has been extended to construct a high‐performance lithium‐ion battery and a lithium/sodium/potassium‐ion capacitor. [ABSTRACT FROM AUTHOR]

Antimony (Sb) is considered a promising anode material for sodium‐ion batteries due to its high specific capacity and moderate working potential. However, the non‐negligible volume variation leads to the rapid decay of capacity, which hinders the practical application of Sb anode materials. Here, an economical and scalable route with high yield is proposed to obtain Sb ultrafine nanocrystals embedded in a porous carbon skeleton. Notably, the synergetic effect of the heterogeneous structure is maximized by inducing the interfacial coupling SbOC and creating buffering space for the volume effect of Sb. The high‐entropy phase interface creates the doping site breaking the periodicity of atoms and alters the electronic structure, also bridging the slip of intergranular defects. Thus, the electronic conductivity and phase interface structural stability are reinforced. The mechanism of accelerating electron migration at the heterogeneous phase interface is visualized through the density functional theory method, and the mass/charge‐transfer kinetics is analyzed via the calculation of surface‐induced capacitive contribution. [ABSTRACT FROM AUTHOR]

Attributed to the high theoretical capacity and abundant reserve, Cu3Mo2O9 has been considered as a potential anode material for lithium‐ion batteries. Nevertheless, the severe capacity fading caused by structure collapse and particle aggregation seriously hinders its practical application. In this work, Cu3Mo2O9 coated with homogeneous polyaniline layer is obtained through oxidative polymerization of aniline on the surface of Cu3Mo2O9. The lithium storage performance is investigated systematically. As a result, a high reversible specific capacity of 800.2 mA h g−1 at a current density of 100 mA g−1 is delivered in Cu3Mo2O9@PANI anode even after 200 cycles, which is much higher than that of pristine Cu3Mo2O9 anode (373.8 mA h g−1). Furthermore, a high capacity of 675 mA h g−1 at a high current density of 1 A g−1 is achieved even after 700 cycles. This result evidences that the introduction of a polyaniline protective layer is an effective way to improve the structural stability of the Cu3Mo2O9 anode and further enhance cycling durability. This strategy is a starting point for the preparation and stabilization of other binary metal oxide composite materials for applications in lithium‐ion batteries. Icing on the cake: Cu3Mo2O9@PANI composites are designed as anode material for lithium‐ion batteries (LIB). The prepared electrode exhibits excellent lithium storage performance. An especially good cyclic stability is found, with a delivered stable reversible capacity of 675 mA h g−1 even after 700 cycles at a high current density of 1 A g−1. [ABSTRACT FROM AUTHOR]

Abstract: Designing potential anodes for sodium‐ion battery with both remarkable durability and high‐rate capability has captured enormous attention so far. The engineering of size and morphology is deemed as an effective manner to boost the electrochemical properties. Owing to the anisotropic self‐assembly of iron selenide, rod‐like FeSe2 coates with nitrogen‐doped carbon is prepared through the thermal reaction of Prussian blue with selenium. Notably, the cyano groups are effectively transformed into N‐doped carbon with FeNC bonds, which uniformly coats FeSe2, prompting Na+ transportations. Interestingly, the particle size is tailored by heating rates, along with increased carbon content, leading to broadened energy levels for redox reaction. Bestowed by these advantages, the FeSe2/N‐C as Na‐storage anode delivers impressive electrochemical properties. Even at a rather high rate of 10.0 A g−1, a considerable capacity of 308 mAh g−1 is yielded over 10 000 loops. Supported by the detailed analysis of kinetic features, reduced size of particles could bring about the enhanced contributions of pseudocapacitive and quickening rate of ions transferring. The phase evolutions are further investigated by in situ EIS and ex‐situ technologies. The work is expected to provide a new strategy to prepare metal‐selenide with controllable size and induce the faster kinetic of high‐rate materials. [ABSTRACT FROM AUTHOR]

Rod-like α-MoO 3 is successfully designed by alternating voltage induced electrochemical synthesis (AVIES) approach. The morphology and texture of MoO 3 is effectively controlled by applying various calcination temperature of 300–600 °C. Notably, the α-MoO 3 microrods growing along [001] direction have the high aspect ratio, and the randomly stacked structure can facilitate the charge transfer and offer more active sites for sodium storage. When utilized for sodium-ion batteries, it presents the high charge capacities of 305 mAh g −1 at 1C and 143 mAh g −1 at 10C. Even after 3000 cycles at 10C, a significant capacity of 108 mAh g −1 is still delivered, highlighting its marvelous electrochemical properties. This work may be a compelling exploration for developing metal/metal oxides materials for sodium storages by AVIES. [ABSTRACT FROM AUTHOR]

Sb/acetylene black (Sb/AB) composite was firstly applied as anode for sodium-ion batteries (SIBs). A great electrochemical performance of the composite was obtained when utilizing this composite for SIBs. It was found that the charge capacity can reach 473 mAh g −1 in the 70th cycle at a current density of 100 mA g −1 , and we also note that the capacity contributed by Sb was about 624 mAh g −1 , which is very close to its theoretical sodium storage capacity (660 mAh g −1 corresponding to a formula of Na 3 Sb), demonstrating the full utilization of Sb. It is interesting to see that even at a high current density of 1600 mA g −1 , the capacity can still reach 281 mAh g −1 . [ABSTRACT FROM AUTHOR]

The booming development of the lithium-ion battery market has aroused the transformation of people's consumption and life style. As a significant branch of lithium-ion batteries, LiFePO 4 (LFP)-type batteries has been widely employed in electric vehicles and energy storage devices due to its high safety and decent charge-discharge stability. Nevertheless, the resulted massive scrap of LFP batteries will greatly pose environmental threats and waste of resources if appropriate technical means are not adopted. The advanced recycling methods of spent LFP cathode have long been constantly explored in recent years but have not been systematically discussed. Hence, this review comprehensively summarizes the recovery technologies of spent LiFePO 4 cathode in the current status, including traditional pyro-/hydro-metallurgical processes, direct regeneration and other innovative methods, etc. Furthermore, the pretreatment process is also covered to promote all-sided understanding of the development of LFP cathode recovery approaches. Based on the systematic analysis of spent LFP cathode recycling, the future outlook of efficient recycling methods is proposed to promote the sustainable development of spent lithium-ion batteries. Schematic illustration of strategies and characteristics towards spent LFP cathode recycling. [Display omitted] • A comprehensive summary and prospect of spent LFP cathode recycling. • Pretreatment is introduced to ensure deep understanding of recycling implication. • Mainstream recycling technologies of spent LFP battery are reviewed. • Up-to-date novel recycling methods for spent LFP cathode are summarized. • Future challenges and perspectives are proposed to promote efficient recycling. [ABSTRACT FROM AUTHOR]

The ultrathin TiO 2 nanosheets doped by nitrogen tightly attaching on carbon nanotubes are designed and evaluated as anode for sodium ion batteries. The TiO 2 nanosheets attaching on carbon nanotubes composite shows a high specific capacity of 248.5 mAh g −1 at the rate of 0.5 C, and it can still deliver a specific capacity of 100.9 mAh g −1 at a high rate of 20 C, which verifies an outstanding sodium storage capacity and an excellent rate capability. More encouragingly, at a rate of 10 C, the specific capacity can be still kept at 154.2 mAh g −1 after 3500 cycles, displaying a remarkable long-term cyclic stability. Note that the corresponding kinetics analysis suggests that the pseudocapacitive behaviour is responsible for the updating sodium storage performances of TiO 2 nanosheets composite. Additionally, the cooperation effects of carbon nanotubes preservation and nitrogen modification can provide fast electronic pathways, and the TiO 2 nanosheets can promote sodium ions transport and increase the active sites for sodium storage. The merits of multiple functional and tailor-designed strategies make contributions to develop high-performance TiO 2 anodes in sodium ion batteries. [ABSTRACT FROM AUTHOR]

Carbon materials have been widely applied in the energy storage devices, however, the preparation of suitable carbon materials for sodium-ion batteries (SIBs) is still a challenge. In this paper, N-doped porous carbon material (NDPCs) with rose-like structure has been successfully prapared through pyrolysis of the as-prepared polyimides in-situ. The NDPCs shows rose-like structure derived from 2D nanosheets, an expanded interlayer distance of 0.387 nm, a high specific surface area of 215.7 m 2 g −1 and the electrochemical performances for Na-ion batteries are systematically investigated. A high reversible specific capacity of 240 mAh g −1 at a current density of 100 mA g −1 is attained and a specific capacity of 224 mAh g −1 is remained even after 100 cycles. Remarkably, even at a high current density of 3.2 A g −1 , the reversible specific capacity of 104 mAh g −1 can be observed. This excellent performance of NDPCs electrode may be ascribed to its superior structure, since the micropore/mesopore might efficiently shorten the diffusion distance of Na-ion and the enlarged interlayer spacing of 0.38 nm is significant for Na-ion insertion/extraction. Significantly, the approach to prepare carbon materials from PI may be generalized to other polymers. [ABSTRACT FROM AUTHOR]

Cube-shaped porous carbon (CPC) was obtained from the carbonization of MOF-5 (Zn 4 O(OOCC 6 H 4 COO) 3 ) crystals and shows abundant micro/mesopores, high mechanical strength, largest surface area (2316 m 2 g −1 , BET method) and good electrical conductivity (a high weight ratio 98.17/1.83 of C/O). When utilized as anode material for sodium-ion batteries, the CPC presents a high overall sodium storage capacity ∼240 mAh g −1 at a current density of 100 mA g −1 after 100 cycles, and maintains a high specific capacity of 100 mAh g −1 after 5000 cycles at a current density of 3200 mA g −1 . For the advantages of this unique carbon framework structure, the CPC might be a promising anode material for the application of SIBs. [ABSTRACT FROM AUTHOR]

A facile route to improve the lithium-storage properties of flake graphite (FG) is proposed through coating pyrolysis carbon from polyvinylidene fluoride (PVDF) assisted by KOH activation. The interplanar distance between the graphene sheets of activated PVDF/FG is enlarged, effectively suppressing the electrode deformation during lithium (de)-intercalation. More edge and porous structures of PVDF/FG arising from KOH activation on graphite flakes contribute to improved electron and ion transport, leading to great improvement in its rate and cycling performances. The initial specific capacity of the activated PVDF/FG is 476.6 mAh g −1 at 50 mA g −1 and when the current increases to 1000 mA g −1 , the value still retains 142.6 mAh g −1 . [ABSTRACT FROM AUTHOR]

Cathodic corrosion, a green electrochemical method, has been employed to obtain Sb nanomaterials utilized as anode material for lithium-ion batteries and sodium-ion batteries. Interestingly, two different corrosion mechanisms are found, coming from the impact of electrolyte, resulting in the formation of hexagonal and amorphous Sb in aqueous and organic solution, respectively. With the help of water-soluble carboxymethyl cellulose binder and the electrolyte additive fluoroethylene carbonate, both hexagonal and amorphous Sb electrodes exhibit good cycling stability when utilized as anode materials for lithium-ion batteries and sodium-ion batteries. Additionally, both the hexagonal and amorphous Sb electrodes show very good rate capability in lithium-ion batteries. Even at high current density (2000 mA g −1 ), the hexagonal and amorphous Sb give reversible capacities of 422 and 379 mA h g −1 , respectively. Surprisingly, when used as anode materials for sodium-ion batteries, the hexagonal Sb electrode exhibits a good rate performance of 632, 625, 569, 515 and 426 mA h g −1 at a current density of 100, 200, 500, 1000, and 2000 mA g −1 , respectively. However, limited rate performance is observed from the amorphous Sb electrode in case of sodium-ion battery due to the large impedance. [ABSTRACT FROM AUTHOR]

• Bi/GO composites with different Bi content were synthesized by a novel and efficient electrochemical method. • Bi 2 O 2 2+and reduced graphene oxide, which make Bi/GO composites possess high ionic and electrical conductivity, were generated during the reaction. • The small volume expansion of Bi/GO composite during sodiation is attributed to the existence of GO. • The Bi/GO composite anode displays superior rate performance and excellent cycling stability. Bismuth, a promising attribute for sodium-ion batteries, which have been attracting significant attention owing to their advantages of high volumetric capacity and suitable operating potential. However, most traditional Bi-based materials are suffered from pulverization and fracture of the electrodes caused by dramatic volume variation, consequently diminishing the cycle stability. Herein, in this work, bismuth embedded within graphene oxide matrices have been obtained by utilizing a novel and efficient electrochemical method. Through the strong reducing properties of Zintl clusters Bi 2 2−, GO is partially reduced to generate reduced graphene oxide with better electrical conductivity. Simultaneously, Bi is strongly loaded on the GO through Bi-O-C bonding, which can form Bi 2 O 2 2+ with excellent ionic conductivity. Moreover, the volume expansion of Bi during sodiation can be effectively buffered in the GO matrices. As a result, this Bi/GO composite exhibits excellent electrochemical performances in sodium-ion batteries (SIBs), including a high specific capacity of 258 mAh g−1 at 10 A g−1 and an excellent cycle stability with high retained capacity of 315 mAh g−1 after 500 cycles at 2 A g−1. This work paves the way to prepare designated promising electrode materials for high-performance SIBs, and thoroughly understands mechanism of electrochemical methods for preparing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Two-dimensional birnessite-type manganese oxide electrochemically exfoliated from non-van der Waals manganese metal shows superior zinc storage performance. • 2D layered birnessite has been electrochemically exfoliated form bulk Mn metal. • Monolayer and few-layer birnessite sheets can be obtained. • The cation content and layer number of birnessites can be tuned. • The exfoliated birnessite provides superior zinc storage performances. • This method is applicable to producing various 2D layered transition metal oxides. Electrochemical exfoliation of layered van der Waals solids is becoming a promising method for the fabrication of two-dimensional (2D) materials beyond graphene. Nevertheless, most of bulk layered starting solids are semiconductive or even nonconductive, which will reduce the exfoliation efficiency. In addition, the strong bonding interaction between the layers of van der Waals crystal will lead to the incomplete exfoliation. These deficiencies will hinder the application of this method in the synthesis of two-dimensional semiconductive and insulating materials. Herein, one-pot electrochemical potential-cycles exfoliation has been introduced to fabricate nonconductive 2D layered birnessite-type manganese oxide utilizing non-layered metal as starting precursor, demonstrating that monolayer and few layer birnessite sheets can be obtained through tuning the potential sweep rate. More importantly, this strategy promotes a high exfoliation yield up to 96%, which is much higher than that of electrochemical exfoliation of layered precursors. Additionally, this method can overwhelm the drawbacks such as hindrance of intrinsic/contact high resistance and incomplete exfoliation of the layered starting material presented by electrochemical exfoliation of bulk layered van der Waals solids. When utilized as cathode material for Zn-ion batteries, the exfoliated birnessite can deliver a capacity of 325 mAh g−1 at a current density of 200 mA g−1 and achieved capacity retention of 84% over 1000 cycles at 1000 mA g−1. As exfoliation parameters can be manipulated, this effective method is applicable to producing various 2D layered transition metal oxides and layered double hydroxides regardless of electric conductivity, which will contribute to plentiful applications. [ABSTRACT FROM AUTHOR]