Fast Ion Research Articles

Can Prussian Blue Analogues be Holy Grail for Advancing Post‐Lithium Batteries?

The recent classification of lithium as a critical raw material surged the R&D of post‐lithium batteries (PLBs). The larger cation charge carriers of these PLBs consequently entailed extensive materials R&D for battery components, especially cathode. Prussian Blue (PB) and its analogues (PBAs) have emerged as promising cathode materials for PLBs due to their desirable characteristics, including a three‐dimensional open framework structure that facilitates fast ion diffusion for both monovalent (Li+, Na+, K+) and multivalent (Mg2+, Ca2+, Zn2+, Al3+) ions, stable framework structures, electrochemical tunability, availability of widely used precursors, and ease of synthesis. Our comprehensive review reveals that several challenges are yet to be addressed in employing PBAs as cathode materials for PLBs, viz., vacancies, crystal water, side reactions, and conductivity issues due to electrochemically inactive components of PBAs. This review paper provides an exhaustive survey of material development, including the mitigation strategies of the challenges in employing PBAs as cathode materials for advancing PLBs.

Integrated Hydrogel-Zn Structure with Modified Interface Realizing Fast Ion Transfer for Long Cycling Zn-ion Battery

Fabrication of gel electrolytes are effective strategy to solve the side reactions and dendrite growth of Zn anodes in aqueous rechargeable zinc batteries (ARZBs). However, complicated synthesis and ex-situ assembled processes lead to poor electrode–electrolyte interfacial contact, which hinders ion transfer. Herein, compatible and stable electrode–electrolyte structure is constructed by in-situ polymerization process. The tightly coupled electrode–electrolyte interface reduces the mass transfer impedance, balances electric field distribution, and thus inhibits dendrites. What’s more, the −SO3H groups in gel electrolyte play a significant role which performs as cation transport channels to regulate the deposition behavior of Zn along (002) crystal plane. The intercanected and porous structure of this electrolyte promote the desolvation process of [Zn(H2O)6]2+ and inhibit the side reaction. As a result, the symmetric cell exhibits ultra-long lifespan over 4,530 h (＞188 days), Zn||Cu cell delivers an average coulombic efficiency (CE) of 99.85 % with 1,000 cycles. Zn||MVO cell operates stably for over 2,700 cycles with CE of 99.91 %. This integrated hydrogel-Zn structure provides broad application prospect in wearable devices.

Modulation of ion-conducting groups in aqueous terpolymer binders to boost the electrochemical performance of silicon-based anodes

Silicon anodes hold great promise for the next-generation energy dense lithium-ion batteries (LIBs) due to their high specific capacity, yet the capacity of silicon anodes rapidly decays during repeated charge/discharge processes, which can hardly be alleviated via conventional binders due to the poor mechanical properties, insufficient ion/electronic conduction, and weak adhesion force. Herein, a random terpolymer (AMS) with fast ion transport and robust adhesion force was developed via the radical polymerization of acrylic acid (AA), acrylamide (AM) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and used as aqueous binder for silicon/graphite (Si/C) anodes. The carboxyl and amide groups from AA and AM can form numerous of hydrogen bonds with the silicon particles, leading to a strong adhesion effect, while the sulfonic acid groups can construct fast channels for the rapid transport of lithium ions. Finally, the Si/C anode using the AMS411 binder delivers a high specific capacity of 322.48 mAh g−1 along with the superior operation stability at 0.5C (high-capacity retention ratio of 80.8 % after 500 cycles). This work provides that the incorporation of specific functional groups effectively enhances the overall electrochemical performance of the silicon-based anodes.

Al-doped Li4SiO4 for cyclic solar energy storage and CO2 capture: An experimental and DFT study

The substantial consumption of fossil fuels gives rise to excessive carbon dioxide emissions, and mitigating them has emerged as a pressing global priority. The use of renewable energy and carbon capture, utilization, and storage are recognized as two major approaches for carbon neutrality. Li4SiO4 materials exhibit promising prospects in both thermochemical heat storage for solar energy power and cyclic high-temperature CO2 capture. The reactivity between Li4SiO4 and CO2 plays the vital role in its energy storage and CO2 capture performance. Herein, we prepare Al-doped Li4SiO4 materials through an impregnated suspension technique, simultaneously achieving high contact areas and lattice defects to enhance both fast chemisorption and ion diffusion processes. The results show that Al-doped Li4SiO4 exhibits high average energy density of 56677.08 kJ/kmol within 30 cycles. Additionally, the granulated Al-doped Li4SiO4-based pellets, produced via the freeze-drying technique, exhibit negligible energy density loss rate of less than 9 % and acceptable mechanical strength. Furthermore, the CO2 sorption performance also reaches a high value of 0.27 g/g. The reaction mechanism between Li4SiO4 and CO2 has been investigated at both macroscopic and microscopic levels through kinetic analysis and DFT calculations. The simulated Al-doped Li4SiO4/CO2 sorption system possesses increased adsorption energy level from −0.81 eV for the undoped one to −0.95 eV, thereby leading to the improved CO2 sorption. In general, Al-doped Li4SiO4 materials demonstrate great potential for applications in thermochemical heat storage and CO2 capture.

Co-Assembly of Polyoxometalates and Porphyrins as Anode for High-Performance Lithium-Ion Batteries.

Polyoxometalates (POMs) have been considered one of the most promising anode candidates for lithium-ion batteries (LIBs) in virtue of their high theoretical capacity and reversible multielectron redox properties. However, the poor intrinsic electronic conductivity, low specific surface area, and high solubility in organic electrolytes hinder their widespread applications in LIBs. Herein, a novel hybrid nanomaterial is synthesized by co-assembling POMs and porphyrins (PMo12/CoTPyP) through a facile solvothermal method. The POM clusters are stabilized by porphyrin units through electrostatic interactions, which simultaneously realize the uniform dispersion of POMs and porphyrin units. Benefiting from the generated sub-1nm channels for fast ion transport and the synergistic effect between evenly distributed PMo12 clusters and high-conductive CoTPyP units, the LIB based on the optimized PMo12/CoTPyP anode exhibits significantly improved Li+ storage capability as well as superior rate and cycling performance. The results of density functional theory simulations further reveal that the co-assembly of PMo12 and CoTPyP can accelerate the mobility of Li+ and electrons, which in turn promotes the enhancement of LIBs performance. This work paves a strategy for synthesizing POMs-based anode materials with simultaneously high dispersibility, redox activity, and stability.

OPTEMIST: A neutral beam for measuring quasi-omnigenity in Wendelstein 7-X

A new neutral beamline (OPTEMIST) uniquely capable of exploring the predicted improvement of fast ion confinement in Wendelstein 7-X (W7-X), which comes with increasing plasma beta, is proposed. As the plasma beta increases in the W7-X device, the high mirror magnetic configuration has drift orbits that begin to close, enhancing the confinement of the deeply trapped particles. The existing neutral beam system is found to produce particle populations that do not adequately probe the deeply trapped orbits. Fast tritons generated by thermal deuterium–deuterium fusion reactions are found to probe the necessary conditions for demonstrating this effect. However, it is found that diagnostically measuring this effect will be difficult. A scoping study of a neutral beamline that directly populates the trapped orbits is performed. It is found that a monoenergetic population of 120 kV injected protons provides the largest confinement enhancement in the fast ion population as the plasma beta is increased. The necessity to raise plasma density to increase plasma beta results in blinding of spectroscopic beam measurements by bremsstrahlung. An array of novel fast ion loss detectors that would adequately assess the confinement of these particles is proposed.

Simulation of a scintillator-based fast ion loss detector for steady-state operation in Wendelstein 7-X (invited).

A quantitative theoretical framework has been created to model neutral beam injection and fast ion losses in the Wendelstein 7-X (W7-X) stellarator, including a novel method to develop synthetic diagnostics for fast ion loss detectors (FILDs) of many types, such as scintillating and Faraday Cup FILDs. This is the first time that this has been done in stellarator geometry with this level of fidelity, providing a way for fast ion losses to be predicted more precisely in future stellarator experiments and in W7-X. Simulations of the signal seen by a Faraday Cup FILD have been completed for multiple W7-X plasmas and show close agreement with the measured signals. This method is now applied to an actively water-cooled, scintillator-based FILD, which is currently in development to measure the fast ion loss distribution in W7-X in greater detail. The design makes use of a double slit to measure energy-and-pitch-angle-resolved losses of both co-going and counter-going fast ions. The diagnostic, which can be inserted to different radial positions, has been designed to withstand steady-state heat fluxes of up to 120 kW/m2 along with additional transient heat loads of 100 kW/m2 lasting for up to 20s at a time. Simulations of W7-X standard magnetic configuration show up to 8 × 1013 (s-1 cm-2) ion fluxes onto the sensor from each neutral beam source and no signal from the counter-going slit. These simulations will help inform experimental proposals for future W7-X campaigns after installation of this diagnostic.

Ti─O─C Bonding at 2D Heterointerfaces of 3D Composites for Fast Sodium Ion Storage at High Mass Loading Level.

3D composite electrodes have shown extraordinary promise as high mass loading electrode materials for sodium ion batteries (SIBs). However, they usually show poor rate performance due to the sluggish Na+ kinetics at the heterointerfaces of the composites. Here, a 3D MXene-reduced holey graphene oxide (MXene-RHGO) composite electrode with Ti─O─C bonding at 2D heterointerfaces of MXene and RHGO is developed. Density functional theory (DFT) calculations reveal the built-in electric fields (BIEFs) are enhanced by the formation of bridged interfacial Ti─O─C bonding, that lead to not only faster diffusion of Na+ at the heterointerfaces but also faster adsorption and migration of Na+ on the MXene surfaces. As a result, the 3D composite electrodes show impressive properties for fast Na+ storage. Under high current density of 10mAcm-2, the 3D MXene-RHGO composite electrodes with high mass loading of 10mgcm-2 achieve a strikingly high and stable areal capacity of 3mAhcm-2, which is same as commercial LIBs and greatly exceeds that of most reported SIBs electrode materials. The work shows that rationally designed bonding at the heterointerfaces represents an effective strategy for promoting high mass loading 3D composites electrode materials forward toward practical SIBs applications.

Doping P heteroatoms into thin-wall polypyrrole hollow nanobelts with enhanced electrochemical performance for aqueous Zn ion storage

The aqueous zinc-ion batteries are promising to be large-scale energy technologies for solving the contradiction between the intermittency of renewable energy and the immediacy of growing electricity demand. Conductive polymers have been utilized as cathode materials for Zn ion storage but suffered from inadequate active sites, resulting in poor specific capacity. In this work, P doping polypyrrole hollow nanobelts (P-PPy HNBs) with long aspect ratio have been prepared by in-situ polymerization of pyrrole on a template of MoO3 nanotubes. Owing to the long-aspect-ratio hollow structure, the P-PPy HNBs perform thin wall, large surface area, porous structure with micropores and mesopores, which is beneficial to high and fast Zn ion storage. Remarkably, the as-obtained P-PPy HNBs cathodes in this work deliver favorable electrochemical performance for Zn2+ storage in terms of good capacity, rate capability and cycling stability. Moreover, kinetic analysis quantitatively confirms the capacitive contribution of NPCNTs is dominant for aqueous Zn ion storage. The capacitive properties are contributed that the synergistic effect of porous and hollow nanobelt structure construction and P doping strategy can provide abundant active sites and promote electronic conductivity and ion transport. Generally, the strategy for hollow structure with a long aspect ratio and heteroatom doping in our work causes excellent-performance properties, possibly bringing light on the future design of other cathodes for aqueous Znic-based energy storage devices.

Electric field induced molecular orientation to construct the composite polymer electrolytes with vertically aligned ion diffusion pathways for stable solid-state lithium metal batteries

Fabricating flexible composite polymer electrolytes (CPEs) with vertically aligned ion transport pathways is necessary for the application of solid-state lithium metal batteries (LMBs), yet the orientation of polymer matrix usually is disorder, thus the improvement in ionic conductivity is unsatisfied. Herein, we develop a simple electric field induced molecular orientation strategy to fabricate the flexible CPEs with vertically aligned ion transport pathways. Driven by direct current (DC) electric field (e.g. 1.5 MV m−1), the polar 15C5-Li+ dipoles and monomer molecules are oriented regularly and cured to form flexible three dimension (3D) cross-linked structure. As a result, numerous vertically-aligned ion transport pathways have been generated in the vertically oriented arrangement CPEs, thus presenting highly enhanced ionic conductivities, mechanical strength and superb inhibition ability to lithium dendrite growth. When used as CPEs for Li||LiFePO4 (LFP) batteries, the vertically oriented CPEs exhibit excellent rate and long-term cycle stability with a reversible discharge capability of 124.9 mAh g−1 after 350 cycles at 1C and 60 °C. However, the randomly oriented CPEs deliver much poor cycle and rate performance at the same conduction. It can also be compatible with NCM811|Li batteries at 30 °C. Therefore, our simple DC electric field induced molecular orientation strategy holds a great application promise to construct the fast ion transport channels for the all-solid-state LMBs.

Ultra-fast switching of energy efficient electrochromic nickel oxide thin films for smart window applications

In today's modern world, energy consumption continues to escalate. In such cases, smart windows play a crucial role in reducing energy consumption and enhancing the quality of life. Electrochromic devices (ECDs) -based smart windows rely profoundly on nickel oxide (NiO) thin films, which act as a counter electrode in ECDs. This work aims to fabricate NiO thin films, with the intention of achieving ultrafast ECD. Through the sputtering technique, energy-efficient ECD is obtained with the highest optical modulation of 60 % at a rapid switching speed of 0.55s for bleaching and 0.95s for coloration. We have also investigated the structural, morphological, vibrational, and optical properties of NiO thin films. XRD analysis revealed the less crystalline or near amorphous nature of NiO thin film. XPS, PL, and Raman studies confirm the existence of defects in the film. The favourable, less crystalline nature, along with the presence of defects, facilitates ultra-fast ion intercalation and de-intercalation process. We believe that prepared NiO film can be used as a promising anodic colourant in electrochromic smart windows with applications in energy-efficient buildings.

Simultaneous determination of several forms of phosphate in food by ion exchange chromatography

The phosphate group is a group of food additives commonly used for moisturizing, improving the structure, and retaining the color and flavor of products prepared from meat, fish, milk, baked goods, and beverages. A reliable and fast ion exchange chromatography method developed for the simultaneous determination of several forms of phosphate (orthophosphoric acid; pyrophosphate, triphosphate, and hexametaphosphate) in food. Samples were extracted with deionized water at a temperature of 25 ± 5oC for 30 minutes. The extracts were determined by ion exchange chromatography under the conditions: Dionex IonPacTM AS11 column (4 x 250 mm, 9 µm) and Dionex IonPaxTM AG11 column (4 x 50 mm, 9 µm) with the gradient program of KOH concentration from 20 mM to 80 mM. The flow rate is 1 mL/min. The method has good specificity, the calibration curves of the four substances have correlation coefficient values R2 > 0.9999, repeatability and recovery meet the requirements of AOAC. The detection limits (LOD) and quantification limit (LOQ) of each substance in the phosphate group are 12 mg/kg and 40 mg/kg, respectively. The method was applied to simultaneously determine several forms of phosphate in 50 food samples: 15/50 samples detected pyrophosphate, 2/50 samples detected triphosphate, 18/50 samples detected hexametaphosphate and 44/50 samples detected ortho-phosphoric acid, 6/50 samples not detected any form of phosphate. The concentration of phosphate group in detected samples varied from 67.9 mg/kg to 2499 mg/kg.

Melting of W/Cu flat type component for main limiter and its impact on plasma operation in EAST experiments

A type of actively cooled W/Cu flat-type component with high heat exhaust capacity was installed as limiter during the EAST spring plasma campaign in 2022, aiming to support the long pulse operation. Unfortunately, severe melting phenomena with obvious droplets ejection of the flat-type W/Cu limiter was repeatedly monitored by CCD and IR cameras, which not only induced the failure of component but also seriously influenced plasma operation. The high temperature around midplane of W/Cu flat-type main limiter is identified to be closely connected with ICRF induced fast ions loss. Indeed, the surface temperature of W/Cu flat-type main limiter was too high to ignore. The damage of flat-type structure, however, usually started between the joint interface of W plates and CuCrZr heat sink material. Such damage would in turn lead to the gradual increase of surface temperature which eventually would cause melting of W plates. Once melting events occurred on the W/Cu flat-type main limiter, the vast majority of cases would result in plasma disruption. Moreover, the damage of main limiter would rapidly deteriorate. Hence, more attention should be paid to how to improve the fatigue lifetime of the joint interface. Such test results of flat-type W/Cu component for limiter are important references for the improvement and application of W/Cu flat-type component for high heat flux area in fusion devices.

Novel ultrastable 2D MOF/MXene nanofluidic membrane with ultralow resistance for highly efficient osmotic power harvesting

Two-dimensional (2D) materials have shown great potential in harvesting osmotic power due to their high membrane selectivity, but the high resistance from tortuous pathways of 2D nanofluidic membranes still impedes the further improvement in output performance. Here, we report an innovative 2D MXCT (MXene/Cu-TCPP) lamellar membrane with ultralow resistance for highly efficient osmotic power generation. The incorporation of 2D Ti3C2Tx MXene with rich functional groups not only resolves the water-stability issue of 2D metal-organic framework (MOF) Cu-TCPP, but provides large surface charges for selective ion transport. The orderly sub-2 nm framework channels of Cu-TCPP provide much shorter permeation pathways for fast ion transport, thus endowing the MXCT membrane with ultralow resistance. Consequently, the MXCT membrane reaches an ultrahigh power output of ∼8.29 W/m2 by mixing seawater and river water, which is ∼275 % higher than that of the pristine MXene membrane. Additionally, it outperforms all the reported single-layer 2D nanosheet-based osmotic power generators under the same experimental conditions in terms of output power and internal resistance (9 kΩ). This work presents a reliable strategy for stabilizing 2D Cu-TCPP MOF in electrolytes, opening new avenues for designing promising 2D nanofluidic membranes for efficient blue energy harvesting and ionic devices.

Rapid Mining of Fast Ion Conductors via Subgraph Isomorphism Matching.

The rapidly evolving field of inorganic solid-state electrolytes (ISSEs) has been driven in recent years by advances in data-mining techniques, which facilitates the high-throughput computational screening for candidate materials in the databases. The key to the mining process is the selection of critical features that underline the similarity of a material to an existing ISSE. Unfortunately, this selection is generally subjective and frequently under debate. Here we propose a subgraph isomorphism matching method that allows an objective evaluation of the similarity between two compounds according to the topology of the local atomic environment. The matching algorithm has been applied to discover four structure types that are highly analogous to the LiTi2(PO4)3 NASICON prototype. We demonstrate that the local atomic environments similar to LiTi2(PO4)3 endow these four structures with favorable Li diffusion tunnels and ionic conductivity on par with those of the prototype. By further taking into account the electronic structure and electrochemical stability window, 13 compounds are identified to be potential ISSEs. Our findings not only offer a promising approach toward rapid mining of fast ion conductors without limitation in the compositional range but also reveal insights into the design of ISSEs according to the topology of their framework structures.

Radial channel boosting stress release in hollow carbon spheres for high-rate sodium ions storage

Carbon spheres are appealing anode materials for advanced sodium ions batteries. However, several major hurdles to address are the stress-accumulation associated with the drastic volume change, the sluggish sodium ions diffusion kinetics, and poor electrochemically active sites inside. Herein, the von Mises stress distribution uncovers the critical role of the radial channel on the strain relaxation behavior based on the finite element method. Based on the finite element simulation, the radial porous hollow carbon spheres are proposed and synthesized by a universal strategy with a hard-template approach and dynamic graphitization. RPHCSs dominate opened micro-mesoporous features through the shell. With fast sodium ion diffusivity kinetics and much more accessible electrochemical active sites in shell, RPHCSs electrodes deliver a high specific capacity of 103.0 mAh g−1 even at 4000 mA g−1 with a high capacity contribution ratio > 0.1 V (81.1 %), suggesting its great superiority in the application of high-rate sodium ions storage. Such architecture provides a promising structural platform for the fabrication of high-performance carbon spheres material for other electrochemical energy storage systems.

Redox-active “Structural Pillar” molecular doping strategy towards High-Performance polyaniline-based flexible supercapacitors

To coordinate flexibility to electrodes without sacrificing their electrochemical properties is critical for the development of wearable supercapacitors (SCs). Polyaniline (PANI) is well-known pseudocapacitive electrode material due to its high conductivity and different oxidation states upon switchable structures. However, its rigid conjugated backbone and structural instability caused by repeated doping/de-doping during cycling severely impede its utilization in flexible SCs. Herein, we deploy a directional freezing and redox-active “structural pillar” molecular doping strategy to boost PANI-based flexible SCs with high performance. The directional freezing strategy constructs an interconnected 3D honeycomb hydrogel structure with PANI nanofibers, which guarantees fast ion diffusion and electron transport and meanwhile exposes abundant active sites. The large-sized dopant 2-amino-4-bromoanthraquinone-2-sulfonic acid sodium (AQNS) is used as the structural pillar to alleviate the structural instability of PANI during cycling and provides additional pseudocapacitance arising from its redox active quinone groups. Moreover, the negatively charged −SO3− on AQNS can further interact with H+ in the electrolyte to act as an internal proton reservoir, assisting the protonation of –NH- and −N = in PANI to facilitate its charge storage process. Consequently, the PANI-AQNS electrode achieves a high specific capacitance of 578 F g−1 at 1 A g−1 and its symmetric SCs exhibit a specific capacitance of 199 F g−1 at 0.5 A g−1 with an energy density of 13.61 W h kg−1 at a power density of 175 W kg−1. Upon 2000 cycles of dynamic deformations, the SCs can still maintain above 90 % of the initial capacitance, verifying their excellent flexibility-relevant property.

Thermographic observation of fast ion impact areas in the NBI ducts of TJ-II

Infrared thermography has been used to study the fast ion impact areas in the Co and Counter NBI ducts of TJ-II. Statistical results of the distribution of accumulated impacts on the walls of the duct have been obtained with an ion trajectory code. A more realistic description is obtained by coupling a beam simulation code to produce the ion birth point distribution. In this way, the main interception areas for both injectors have been found. Those areas constitute the Regions of Interest (ROI's) for the IR thermography system. The up-graded IR system, with its high definition MIR camera, enlarged window, and precision support and displacement mechanisms for camera and mirror, allows such ROI's to be captured. The optimal alignment parameters of the camera and mirror have been obtained with the optical simulation code ZEMAX, and the feasibility of the mechanical configuration in the crowded window environment has been checked with a CAD program, also used to simulate the field of view inside the ducts. Finally, infrared images of the ducts during beam pulses without magnetic field and with magnetic field have been compared, to obtain highlighted images of the fast ion impact areas in both ducts, showing the expected stellarator symmetry.

Overview of fast particle experiments in the first MAST Upgrade experimental campaigns

MAST-U is equipped with on-axis and off-axis neutral beam injectors (NBI), and these external sources of super-Alfvénic deuterium fast-ions provide opportunities for studying a wide range of phenomena relevant to the physics of alpha-particles in burning plasmas. The MeV range D-D fusion product ions are also produced but are not confined. Simulations with the ASCOT code show that up to 20% of fast ions produced by NBI can be lost due to charge exchange (CX) with edge neutrals. Dedicated experiments employing low field side (LFS) gas fuelling show a significant drop in the measured neutron fluxes resulting from beam-plasma reactions, providing additional evidence of CX-induced fast-ion losses, similar to the ASCOT findings. Clear evidence of fast-ion redistribution and loss due to sawteeth (ST), fishbones (FB), long-lived modes (LLM), Toroidal Alfvén Eigenmodes (TAE), Edge Localised Modes (ELM) and neoclassical tearing modes (NTM) has been found in measurements with a Neutron Camera (NCU), a scintillator-based Fast-Ion Loss Detector (FILD), a Solid-State Neutral Particle Analyser (SSNPA) and a Fast-Ion Deuterium-α (FIDA) spectrometer. Unprecedented FILD measurements in the range of 1–2 MHz indicate that fast-ion losses can be also induced by the beam ion cyclotron resonance interaction with compressional or global Alfvén eigenmodes (CAEs or GAEs). These results show the wide variety of scenarios and the unique conditions in which fast ions can be studied in MAST-U, under conditions that are relevant for future devices like STEP or ITER.

Aluminum vacancy‐rich MOF‐derived carbon nanosheets for high‐capacity and long‐life aqueous aluminum‐ion battery

AbstractEco‐friendly and safe aqueous aluminum‐ion batteries as energy storage devices with low economic burden, high stability and fast ion transport have been lucubrated deeply in response to the call for sustainable development. However, the poor cycle performance caused by difficult (de‐)intercalation hinders the development prospect. In this work, the aluminum vacancy‐rich MOF‐derived carbon is constructed to achieve reversible aluminum storage during the charge‐discharge cycles. The MOF‐derived carbon with anti‐stacking waxberry‐like structure exhibits high capacity (282.1 mAh g−1 at 50 mA g−1) and long cycle performance (84.4% capacity retention rate at 1 A g−1 after 5000 cycles). Further investigations demonstrate that (de‐)intercalation occurs among the vacancies of carbon nanosheets in the form of hydrated aluminum ions. Meanwhile, the introduced nitrogen as energy storage sites contributes part of the capacity. The proposed aluminum vacancy engineering improves the current situation of the capacitive energy storage mode for 2D carbon materials, which may exploit an advanced theoretical model for the design of aqueous batteries.