Coupling Sb_(2)WO_(6)microflowers and conductive polypyrrole for efficient potassium storage by enhanced conductivity and K^(+) diffusivity

Although metal oxide compounds are considered as desirable anode materials for potassium-ion batteries(PIBs)due to their high theoretical capacity,the large volume variation remains a key issue in realizing metal oxide anodes with long cycle life and excellent rate property.In this study,polypyrroleencapsulated Sb_(2)WO_(6)(denoted Sb_(2)WO_(6)@PPy)microflowers are synthesized by a one-step hydrothermal method followed by in-situ polymerization and coating by pyrrole.Leveraging the nanosheet-stacked Sb_(2)WO_(6)microflower structure,the improved electronic conductivity,and the architectural protection offered by the PPy coating,Sb_(2)WO_(6)@PPy exhibits boosted potassium storage properties,thereby demonstrating an outstanding rate property of 110.3 m A h g^(-1)at 5 A g^(-1)and delivering a long-period cycling stability with a reversible capacity of 197.2 m A h g^(-1)after 500 cycles at 1 A g^(-1).In addition,the conversion and alloying processes of Sb_(2)WO_(6)@PPy in PIBs with the generation of intermediates,K_(2)WO_(4)and K_(3)Sb,is determined by X-ray photoelectron spectroscopy,transmission electron microscopy,and exsitu X-ray diffraction during potassiation/depotassiation.Density functional theory calculations demonstrate that the robust coupling between PPy and Sb_(2)WO_(6)endues it with a much stronger total density of states and a built-in electric field,thereby increasing the electronic conductivity,and thus effectively reduces the K^(+)diffusion barrier.

Tuning the electron transport behavior at Li/LATP interface for enhanced cyclability of solid-state Li batteries

An interlayer is usually employed to tackle the interfacial instability issue between solid electrolytes(SEs)and Li metal caused by the side reaction.However,the failure mechanism of the ionic conductor interlayers,especially the influence from electron penetration,remains largely unknown.Herein,using Li1.3Al0.3Ti1.7(PO4)3(LATP)as the model SE and LiF as the interlayer,we use metal semiconductor contact barrier theory to reveal the failure origin of Li/LiF@LATP interface based on the calculation results of density functional theory(DFT),in which electrons can easily tunnel through the LiF grain boundary with F vacancies due to its narrow barrier width against electron injection,followed by the reduction of LATP.Remarkably,an Al-LiF bilayer between Li/LATP is found to dramatically promote the interfacial stability,due to the highly increased barrier width and homogenized electric field at the interface.Consequently,the Li symmetric cells with Al-LiF bilayer can exhibit excellent cyclability of more than 2,000 h superior to that interlayered by LiF monolayer(~860 h).Moreover,the Li/Al-LiF@LATP/LiFePO4 solid-state batteries deliver a capacity retention of 83.2%after 350 cycles at 0.5 C.Our findings emphasize the importance of tuning the electron transport behavior by optimizing the potential barrier for the interface design in high-performance solid-state batteries.

Rational design of three-dimensional branched NiCo-P@CoNiMo-P core/shell nanowire heterostructures for high-performance hybrid supercapacitor

Owing to the dramatically enhanced charge-mass transport and abundant electrochemically active sites,transition metal compound electrodes are increasingly attractive for achieving high-performance supercapacitors(SCs).Here,we report the fabrication of nickel foam supported three-dimensional(3 D)branched nickel-cobalt phosphides@tri-metal cobalt-nickel-molybdenum phosphides core/shell nanowire heterostructures(denoted as NiCo-P@CoNiMo-P)as high-performance electrode materials for hybrid supercapacitors.The presence of multiple valences of the cations in such NiCo-P@CoNiMo-P enables rich redox reactions and promoted synergy effects.Benefiting from their collective effects,the resulting electrode demonstrates high specific capacity of 1366 C g^(-1) at 2 A g^(-1)(2.03 C cm^(-2) at2 mA cm^(-2))and 922 C g^(-1) at 10 A g^(-1),as well as good cycling stability(retaining~94%of the initial capacity after 6000 cycles at 15 A g^(-1)).A hybrid SC using the NiCo-P@CoNiMo-P as the positive electrode and N-doped rGOs as the negative electrode exhibits a high energy density of 81.4 Wh kg^(-1) at a power density of 1213 W kg^(-1) and a capacity retention of 132%even after 6000 cycles at 10 A g^(-1).Our findings can facilitate the material design for boosting the performance of transition metal compounds based materials for fast energy storage.

Reduced Ti-MOFs encapsulated black phosphorus with high stability and enhanced photocatalytic activity

The generation of green hydrogen(H_2) energy is of great significance to solve worldwide energy and environmental issues. Reduced Ti based photocatalyst has recently attracted intensive attention due to its excellent photocatalytic activity, while the synthesis of reduced Ti based photocatalysts with high stability is still a great challenge. Here, we report a facile method for synthesis of reduced Ti metal organic frameworks(small amounts of Pt incorporated) encapsulated BP(BP/R-Ti-MOFs/Pt) hybrid nanomaterial with enhanced photocatalytic activity. The strong interaction between Ti and P reduces the valence state of the binding Ti^(4+)on the BP surface, forming abundant reduced Ti^(4+)within R-Ti-MOFs/BP. Such reduced Ti^(4+)render R-Ti-MOFs/BP efficient charge transfer and excellent light absorption capability, thus promote the photocatalytic H_2 production efficiency. Furthermore, the Ti-P interaction stabilizes both reduced Ti^(4+)and BP during the photocatalytic reaction, which greatly enhanced the stability of the obtained BP/R-TiMOFs/Pt photocatalyst.

Boosting the Electrochemical Performance of Li-and Mn-Rich Cathodes by a Three-in-One Strategy

There are plenty of issues need to be solved before the practi-cal application of Li-and Mn-rich cathodes,including the detrimental voltage decay and mediocre rate capability,etc.Element doping can e ectively solve the above problems,but cause the loss of capacity.The introduction of appropriate defects can compensate the capacity loss;however,it will lead to structural mismatch and stress accumulation.Herein,a three-in-one method that combines cation–polyanion co-doping,defect construction,and stress engineering is pro-posed.The co-doped Na^(+)/SO_(4)^(2-)can stabilize the layer framework and enhance the capacity and voltage stability.The induced defects would activate more reac-tion sites and promote the electrochemical performance.Meanwhile,the unique alternately distributed defect bands and crystal bands structure can alleviate the stress accumulation caused by changes of cell parameters upon cycling.Consequently,the modified sample retains a capacity of 273 mAh g^(-1)with a high-capacity retention of 94.1%after 100 cycles at 0.2 C,and 152 mAh g^(-1)after 1000 cycles at 2 C,the corresponding voltage attenuation is less than 0.907 mV per cycle.

Production of the C/TiO_(2)composite with a high-performance electrochemical property from titanium-rich sludge via in-situ C coating

Resource recycling from waste-water and sludge is an important part of the 14th Five-Year Plan in China.The emerging titanium-based coagulants have drawn growing attentions due to their strong coagulation capability in water purification and value-added Ti-loaded sludge production.Management and recovery of the high value-added sludge into functional nanomaterials is highly significant for both sludge reduction and environmental remediation.The present study was carried out to investigate the recycle of the coagulated Ti-loaded sludge to produce functional C/TiO_(2)composites as the anode materials for lithium-ion batteries(LIBs).It is the first time that the application of the Ti-loaded wastewater sludge derived C/TiO_(2)was evaluated for LIBs.The experimental results showed that the carbon coating through in-situ carbonization of the sludge produced the C/TiO_(2)composites with a high specific surface area,stable structural integrity,and excellent electrochemical properties that would facilitate Li+diffusion in long-term LIBs usage.The C/TiO_(2)composites calcinated from the polytitanium sulfate-coagulated sludge at 800℃(N_(2))exhibited the best electrochemical performance during the cycling tests(601 m Ah/g at 100 m A/g after 200 cycles).The research work demonstrates the promising prospect of the recycle and value-added utilization of the Ti-loaded sludge in the production of high-performance C/TiO_(2)composites for energy storage applications.This study provides a new way for the management and reuse of Ti-loaded waste-sludge.

Advanced surface engineering of titanium materials for biomedical applications:From static modification to dynamic responsive regulation

Titanium(Ti)and its alloys have been widely used as orthopedic implants,because of their favorable mechanical properties,corrosion resistance and biocompatibility.Despite their significant success in various clinical applications,the probability of failure,degradation and revision is undesirably high,especially for the patients with low bone density,insufficient quantity of bone or osteoporosis,which renders the studies on surface modification of Ti still active to further improve clinical results.It is discerned that surface physicochemical properties directly influence and even control the dynamic interaction that subsequently determines the success or rejection of orthopedic implants.Therefore,it is crucial to endow bulk materials with specific surface properties of high bioactivity that can be performed by surface modification to realize the osseointegration.This article first reviews surface characteristics of Ti materials and various conventional surface modification techniques involving mechanical,physical and chemical treatments based on the formation mechanism of the modified coatings.Such conventional methods are able to improve bioactivity of Ti implants,but the surfaces with static state cannot respond to the dynamic biological cascades from the living cells and tissues.Hence,beyond traditional static design,dynamic responsive avenues are then emerging.The dynamic stimuli sources for surface functionalization can originate from environmental triggers or physiological triggers.In short,this review surveys recent developments in the surface engineering of Ti materials,with a specific emphasis on advances in static to dynamic functionality,which provides perspectives for improving bioactivity and biocompatibility of Ti implants.

Surface-enhanced Raman spectroscopy of morphine in silver colloid

We report the surface-enhanced Raman （SERS） spectra of morphine in silver colloid, and study the silver colloid enhanced effects on the Raman scattering of morphine. The Raman bands of morphine are assigned to certain molecule vibrations. The broad band in the long-wavelength region of the electronic absorption spectra of the sol with added adsorbent at certain concentrations has been explained in terms of the ag- gregation of the colloidal silver particles. The potential applications of SERS in quantitative measurement of the morphine samples are demonstrated. By using a proper Raman band of morphine, the detection limit of morphine in silver sol is found to be 1.5 ng/ml. The result suggests that it is of great significance to use SERS in illicit drug morphine inspection.

NaV6O15:A promising cathode material for insertion/extraction of Mg^2+with excellent cycling performance

The rechargeable magnesium batteries(RMBs)are getting more and more attention because of their high-energy density,high-security and low-cost.Nevertheless,the high charge density of Mg^2+makes the diffusion of Mg2+in the conventional cathodes very slow,resulting in a lack of appropriate electrode materials for RMBs.In this work,we enlarge the layer spacing of V2Os by introducing Na^2+in the crystal structure to promote the diffusion kinetics of Mg^2+.The NaVeO15(NVO)synthesized by a facile method is studied as a cathode material for RMBs with the anhydrous pure Mg^2+electrolyte.As a result,the NVO not only exhibits high discharge capacity(119.2 mAh:g^-1 after 100 cycles at the current density of 20 mA:g^-1)and working voltage(above 1.6 V vs.Mg^2+/Mg),but also expresses good rate capability.Besides,the eX-situ characterizations results reveal that the Mg^2+storage mechanism in NVO is based on the intercalation and deintercalation.The density functional theory(DFT)calculation results further indicate that Mg^2+tends to occupy the semi-occupied sites of Na^+in the NVO.Moreover,the galvanostatic intermittent titration technique(GITT)demonstrates that NVO electrode has the fast diffusion kinetics of Mg^2+during discharge process ranging from 7.55×10^-13 to2.41×10^-11 cm^2·s^-1.Our work proves that the NVO is a potential cathode material for RMBs.

Engineering Two-Phase Bifunctional Oxygen Electrocatalysts with Tunable and Synergetic Components for Flexible Zn-Air Batteries

Metal-air batteries,like Zn-air batteries(ZABs)are usually suffered from low energy conversion efficiency and poor cyclability caused by the sluggish OER and ORR at the air cathode.Herein,a novel bimetallic Co/CoFe nanomaterial supported on nanoflower-like N-doped graphitic carbon(NC)was prepared through a strategy of coordination construction-cation exchange-pyrolysis and used as a highly efficient bifunctional oxygen electrocatalyst.Experimental characterizations and density functional theory calculations reveal the formation of Co/CoFe heterostructure and synergistic effect between metal layer and NC support,leading to improved electric conductivity,accelerated reaction kinetics,and optimized adsorption energy for intermediates of ORR and OER.The Co/CoFe@NC exhibits high bifunctional activities with a remarkably small potential gap of 0.70 V between the half-wave potential(E_(1/2))of ORR and the potential at 10 mA cm^(-2)(E_(j=10))of OER.The aqueous ZAB constructed using this air electrode exhibits a slight voltage loss of only 60 mV after 550-cycle test(360 h,15 days).A sodium polyacrylate(PANa)-based hydrogel electrolyte was synthesized with strong water-retention capability and high ionic conductivity.The quasi-solid-state ZAB by integrating the Co/CoFe@NC air electrode and PANa hydrogel electrolyte demonstrates excellent mechanical stability and cyclability under different bending states.

Construction of 1D/1D WO3 Nanorod/TiO2 Nanobelt Hybrid Heterostructure for Photocatalytic Application

In this work,well-defined 1D/1D WO3 nanorod/TiO2 nanobelt(WNR/TNB)hybrid heterostructure was fabricated by a simple electrostatic self-assembly method.The structure-property correlation was clarified by characterizing the crystal phases,morphologies,optical properties,photoluminescence and photocatalytic performances of the WNR/TNB heterostructures.It was demonstrated that photocatalytic performances of WNR/TNB heterostructure toward mineralization was superior to blank TNB,WNR and randomly mixed counterparts under simulated solar light irradiation,owing predominantly to the intimate interfacial contact between WNR and TNB,forming intimately integrated heterojunction,which promotes the spatial charge carriers transfer and electron relay,hence prolonging the lifetime of photogenerated electron-hole pairs.Moreover,photocatalytic mechanism was elucidated.It is anticipated that our work would provide an alternative strategy to construct diverse heterostructured photocatalysts for solar energy conversion.

In situ TEM observation of neck formation during oriented attachment of PbSe nanocrystals

Oriented attachment of nanocrystals is an important route to constructing epitaxially-connected nanocrystal superlattices for various applications.During oriented attach me nt of semic on ductor nano crystals,neck can be formed betwee n nan ocrystals and it strongly influe nces the properties of the resulting superlattice.However,the neck formation mechanism is poorly understood.Here,we use in situ liquid cell transmission electro n microscopy(TEM)to directly observe the initiatio n and growth of homoepitaxial n ecks betwee n PbSe nano crystals with atomic details.We find that neck initiatio n occurs slowly(~10 s)whe n two nano crystals approach to each other within an edge-to-edge dista nee of 0.6 nm.During neck initiation,Pb and Se atoms defuse from other facets into the gap,forming"dynamic reversible"filaments.Once the filament(n eck)width is larger than a critical size of 0.9 nm,it gradually(15 s)widens into a 3-nm-wide n eck.The atomic structure of the neck is further obtained using ex situ aberration-corrected seanning TEM imaging.Neck initiation and growth mechanisms are elucidated with density functional theory calculati ons.Our direct unveiling of the atomic pathways of neck formatio n duri ng oriented attach me nt shed light into the fabrication of nanocrystal superlattices with improved structural order and electronic properties.

Ag-modified hydrogen titanate nanowire arrays for stable lithium metal anode in a carbonate-based electrolyte

In the investigation of the next-generation battery anode,Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction potential.However,its low columbic efficiency,limited cycling life,and serious safety hazards have hindered the practical application of rechargeable Li metal batteries.Although several strategies have been proposed to enhance the electrochemical performance of Li metal anodes,most are centered around ether-based electrolytes,which are volatile and do not provide a sufficiently large voltage window.Therefore,we aimed to attain stable Li deposition/stripping in a commercial carbonate-based electrolyte.Herein,we have successfully synthesized hydrogen titanate(HTO)nanowire arrays decorated with homogenous Ag nanoparticles(NPs)(Ag@HTO)via simple hydrothermal and silver mirror reactions.The 3 D cross-linked array structure with Ag NPs provides preferable nucleation sites for uniform Li deposition,and most importantly,when assembled with the commercial LiNi_(0.5)Co0.2Mn_(0.3)O_(2) cathode material,the Ag@HTO could maintain a capacity retention ratio of 81.2% at 1 C after 200 cycles,however the pristine Ti foil failed to do so after only 60 cycles.Our research therefore reveals a new way of designing current collectors paired with commercial high voltage cathodes that can create high energy density Li metal batteries.

A homogenous solid polymer electrolyte prepared by facile spray drying method is used for room-temperature solid lithium metal batteries

The aggregation of inorganic particles with high mass ratio will form a heterogeneous electric field in the solid polymer electrolytes(SPEs),which is difficult to be compatible with lithium anode,leading to inadequate ionic conductivity.Herein,a facile spray drying method is adopted to increase the mass ratio of inorganic particles and solve the aggregation problems of fillers simultaneously.The polyvinylidene fluoride(PVDF)with lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)covers the surface of each Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)granules during the nebulization process,then forming flat solid electrolytes via layer-by-layer deposition.Characterized by the atomic force microscope,the obtained solid electrolytes achieve a homogenous dispersion of Young’s modulus and surface electric field.As a result,the as-prepared SPEs present high tensile strength of 7.1 MPa,high ionic conductivity of 1.86×10^(−4)S·cm^(−1)at room temperature,and wide electrochemical window up to 5.0 V,demonstrating increased mechanical strength and uniform lithium-ion migration channels for SPEs.Thanks to the as-prepared SPEs,the lithiumsymmetrical cells show a highly stable Li plating/stripping cycling for over 1,000 h at 0.1 mA·cm^(−2).The corresponding Li/LCoO_(2)batteries also present good rate capability and excellent cyclic performance with capacity retention of 80%after 100 cycles at room temperature.

Tracking the atomic pathways of Pt3Ni-Ni(OH)2 core-shell structures at the gas-liquid interface by in-situ liquid cell TEM

Using the in-situ liquid cell transmission electron microscopy, the three-stage growth of Pt3Ni-Ni(OH)2 core-shell structures at the gas-liquid interfaces was clearly observed, which consists of(1) a thermodynamically driven Pt3Ni alloy core by the monomer attachment,(2) a nickel(Ni) shell formation due to the depletion of the Pt salt precursor, and(3) the oxidation and of the Ni shell into Ni(OH)2 flakes. We also further observed the nucleation and growth of the Ni(OH)2 flakes on an existing layer either at the middle part or at the step edge. More interestingly, the dynamic transformation among a Pt3Ni alloy, Ni clusters and Ni(OH)2 flakes was also imaged even at a high electron dose rate.

Synthesis of yolk-shell Bi_(2)O_(3)@TiO_(2) submicrospheres with enhanced potassium storage

Due to their enormous potential for large-scale energy storage,rechargeable potassium-ion batteries have been widely researched and developed.However,the drastic volume change of electrode materials induced by the huge size of potassium ions during cycling remains a challenge for the construction of stable anodes.Herein,we propose a novel weak acid etching strategy to design and fabricate robust yolk-shell spheres with enough internal void space,in which the Bi_(2)O_(3) nanospheres are well confined in the compartments of TiO_(2) submicrospheres(y-Bi_(2)O_(3)@TiO_(2)).In situ transmission electron microscopy(TEM)and ex situ Xray diffraction(XRD)are conducted to elucidate the structural evolution of y-Bi_(2)O_(3)@TiO_(2) and the interaction between K^(+)and Bi_(2)O_(3) during cycling.Thanks to the yolk-shell nanoarchitecture and the superior buffering property of outer TiO_(2) covering,the as-obtained composite shows a high specific capacity of 383.5 mAh g^(−1) at 100 mA g^(−1),a considerable rate capacity of 134.1 mAh g^(−1) at 2 A g^(−1) and a stable cycling performance of 216.8 mAh g^(−1) at 500 mA g^(−1) over 500 cycles when used for potassium storage.Subsequently,the potassium-ion full battery,constructed by pairing y-Bi_(2)O_(3)@TiO_(2) anode with the thermally annealed 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA)cathode,exhibits an outstanding cycling stability.Hopefully,this carefully-designed strategy can inspire the further development of superior energy storage materials in the near future.

Reversible potassium storage in ultrafine CF_(x): A superior cathode material for potassium batteries and its mechanism

Current studies of cathodes for potassium batteries(PBs) mainly focus on the intercalation-type materials.The conversion-type materials that possess much higher theoretical capacities are rarely discussed in previous literatures.In this work,carbon fluoride(CF_x) is reported as a high capacity conversion-type cathode for PBs for the first time.The material delivers a remarkable discharge capacity of>250 mAh g^(-1) with mid-voltage of 2.6 V at 20 mA g^(-1).Moreover,a highly reversible capacity of around 95 mAh g^(-1) is achieved at 125 mA g^(-1) and maintained for 900 cycles,demonstrating its excellent cycling stability.The mechanism of this highly reversible conversion reaction is further investigated by nuclear magnetic resonance spectra,X-ray diffraction,and transmission electron microscopy studies.According to the analyses,the C-F bond in the cycled material is different from that in the pristine state,which presents relatively higher reversibility.This finding offers important insights for further improving the performance of the CF_x.This work not only demonstrates the CF_x as a high performance cathode for PBs,but also paves a new avenue of exploring conversion-type cathodes for high energy density PBs.

Targeted combination therapy for glioblastoma by co-delivery of doxorubicin,YAP-siRNA and gold nanorods

The combination of brain targeting drug delivery systems and multi-modal intervention pose a promising therapeutic approach for glioblastoma therapy.In this study,we developed an angiopep-2 peptide modified cationic liposome loaded with doxorubicin,YAP-siRNA and gold nanorods(D/R@Ang2-Lip+Au)simultaneously,which has high encapsulating efficiency for doxorubicin(95.4%)and effective binding of siRNA at N/P ratio of 20:1.The fluorescence imaging and flow cytometry analysis revealed high cellular uptake of D/R@Ang2-Lip+Au.Real-time quantitative polymerase chain reaction and western blot analysis indicated that D/R@Ang2-Lip+Au could effectively inhibit the expression of YAP protein.In vitro and in vivo studies showed that D/R@Ang2-Lip+Au had the ability to target glioblastoma cells,and achieved better anti-proliferative effects compared with non-targeted D/R@Lip+Au.Moreover,in vivo experiment demonstrated that D/R@Ang2-Lip+Au was able to cross the blood-brain barrier,and combination therapy could significantly inhibit tumor growth.Therefore,the multifunctional D/R@Ang2-Lip+Au might provide a novel approach for effectively delivery of DOX,YAP-siRNA and AuNRs into the glioblastoma cells simultaneously and exerting synergistic therapeutic effects.

Hydroxyapatite-modified micro/nanostructured titania surfaces with different crystalline phases for osteoblast regulation

Surface structures and physicochemical properties critically influence osseointegration of titanium(Ti)implants.Previous studies have shown that the surface with both micro-and nanoscale roughness may provide multiple features comparable to cell dimensions and thus efficiently regulate cell-material interaction.However,less attention has been made to further optimize the physicochemical properties(e.g.,crystalline phase)and to further improve the bioactivity of micro/nanostructured surfaces.Herein,micro/nanostructured titania surfaces with different crystalline phases(amorphous,anatase and anatase/rutile)were prepared and hydroxyapatite(HA)nanorods were deposited onto the as-prepared surfaces by a spin-assisted layer-by-layer assembly method without greatly altering the initial multi-scale morphology and wettability.The effects of crystalline phase,chemical composition and wettability on osteoblast response were investigated.It is noted that all the micro/nanostructured surfaces with/without HA modification presented superamphiphilic.The activities of MC3T3-E1 cells suggested that the proliferation trend on the micro/nanostructured surfaces was greatly influenced by different crystalline phases,and the highest proliferation rate was obtained on the anatase/rutile surface,followed by the anatase;but the cell differentiation and extracellular matrix mineralization were almost the same among them.After ultrathin HA modification on the micro/nanostructured surfaces with different crystalline phases,it exhibited similar proliferation trend as the original surfaces;however,the cell differentiation and extracellular matrix mineralization were significantly improved.The results indicate that the introduction of ultrathin HA to the micro/nanostructured surfaces with optimized crystalline phase benefits cell proliferation,differentiation and maturation,which suggests a favorable biomimetic microenvironment and provides the potential for enhanced implant osseointegration in vivo.

Editorial

In pursuit of higher energy density,lower cost,longer lifespan and safety,remarkable research efforts have been taken to innovate various types of energy storage materials/devices,especially metal-ion batteries such as Li-ion batteries(LIBs).One of the major challenges is to elucidate the working mechanisms and/or the controlling factors of any new material in a full battery,which requires adequate characterization/diagnosis techniques.Among the numerous electrochemical ex-situ and insitu characterization techniques,magnetic resonance techniques,including nuclear magnetic resonance(NMR),magnetic resonance imaging(MRI)and electron paramagnetic resonance(EPR),are unique in terms of providing structural information at the atomic level and real-time phase and morphology evolution and characterizing ionic motion at various timescales.This special issue is dedicated to an editorial and a selection of papers on the theme of investigating energy storage materials/devices using magnetic resonance techniques.As the guest editors of this special issue,we are honored to introduce the following high-quality research articles and review articles.