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Carrier mobility in titanium dioxide (TiO2) systems is a key factor for their application as energy materials, especially in solar cells and lithium-ion batteries.

The state-of-the-art electronics promote the development of flexible and deformable batteries, which rely on design of advanced structure batteries and fabrication of suitable electrode materials. The current flexible electronics are generally limited by rigidity and nondeformable electrodes. Herein, this work reports an exceeding compressible spongy carbon nanofibers composite anode which was fabricated by electrospinning and gas-forming techniques. The abundant macro/micro porous and loss structure of spongy layers enable the composite electrode exhibited compressible capability and faster ions infiltration ability. And the nest morphology of spongy carbon nanofibers network promised stable conductivity and superior cycling performance of self-standing anodes. The compressible SnO

The improvement of electrochemical performance of lithium-ion (Li-ion) batteries requires in-depth understanding on the structural evolution of electrodes during electrochemical cycling. By taking advantages of sensitive, penetrative and nondestructive properties of neutrons, we adopted in operando neutron diffraction technique to explore structural characteristics of electrodes in LiNi0.5Co0.2Mn0.3O2/Graphite full cell during cycling in real time. It is revealed that the concentration of Li/Ni antisite defects varies and presents regular volcano shape in layered cathode during cycling due to the competition effect between delithiation and magnetic frustration. Moreover, visualization of the Li-ion migration pathway in cathode by maximum entropy method indicates that lithium ions diffuse via tetrahedral site hopping path at the initial state of charge, but a newly-discovered indirect zigzag hopping path dominates afterwards. As for graphite anode counterpart, the intercalation of lithium ions into anode undergoes few distinct stages, including the formation of an intermediate phase with lithium gradient. All these observations concerning the simultaneous structural variation of both cathode and anode unveil the underlying migration behavior of lithium ions in NCM/Graphite full cell and enlighten us to devise an optimized pathway for Li-ion migration toward achieving high-performance Li-ion batteries.

Lithium ions have been applied in the clinic in the treatment of psychiatric disorders. In this work, we report artificial supramolecular lithium channels composed of pore-containing small aromatic molecules. By adjusting the lumen size and coordination numbers, we found that one of the supramolecular channels developed shows unprecedented transmembrane transport of exogenous lithium ions with a Li

The discrepancy between the trend in the diffusion coefficient of a lithium ion (DLi+) and that in the activation energy of ion hopping signals hidden factors determining ion transport kinetics in layered olivine phosphate materials (LiMPO4). Combining density functional theory (DFT) calculations and the Landau–Zener electron transfer theory, we unravel this hidden factor to be the electronic coupling between redox centers of the host materials. The ion transport process in LiMPO4 is newly described as an ion-coupled electron transfer (ET) reaction, where the electronic coupling effect on DLi+ is considered by incorporating the electronic transmission coefficient into the rate constant of the transfer reaction. The new model and DFT calculation results rationalize experimental values of DLi+ for various LiMPO4 (M = Fe, Mn, Co, Ni) materials, which cannot be understood solely by the calculated activation barrier of ion hopping. Interestingly, the electronic coupling between host redox centers is found to play an essential role. Particularly, the sluggish ion mobility in LiFePO4 is due to a very weak electronic coupling. The obtained insights imply that one can improve the rate performance of intercalation materials for metal-ion batteries through modifying the electronic coupling between redox centers of host materials., The discrepancy between the trend in the diffusion coefficient of lithium ions (DLi+) and that in the activation energy of ion hopping signals hidden factors determining ion transport kinetics in layered olivine phosphate materials (LiMPO4).

Li0.45V2O5·0.89H2O (LVO) was successfully synthesized by wet-mixing of LiOH·H2O and V2O5, with subsequent hydrothermal method for the first time. The hydrated lithium ions as the intercalated guest species were inserted into the V2O5 interlayer. The as-obtained LVO with a stable lamellar structure, enlarged interlayer space, weak interlayer repulsive force and low molecular weight, which shows a specific capacitance of 403 mAh g−1 at 0.1 A g−1, excellent rate capability and longlifespan with capacity retention of 86% over 1000 cycles at 10 A g−1. Furthermore, the LVO-based AZIBs possess a synergistic insertion mechanism of Zn2+ and H+, that is the reason for its superior performance. This work provides an efficient design strategy for synthesizing advanced cathode materials for the high-performance Zn2+ energy storage system.

MXenes are the typical ions insertion-type two-dimensional (2D) nanomaterials, have attracted extensive attention in the Li

A kind of layered Li2MSiO4 material, Fe saponite with Na+ pillaring (Na+-FSAP) was developed as a low-cost and environment-friendly lithium-ion storage material. The Na+-FSAP follows the insertion/deinsertion working mechanism accompanied by valence change of Fe from Fe1.86+ to Fe2.71+ (average value) after stabilization, and displays a specific capacity of 125 mAh g–1 at 50 mA g–1 with retention ratio of 80.8% after 75 cycles. The Na+-pillaring effect and abundant structural water in the gallery urge Li+ migrate rapidly, resulting in a large Li+ diffusion coefficient within a range of 10−6.5–10−7.5 cm2 s−1. Thus, the Na+-FSAP provides a model material to design electrode materials with rapid lithium-ion migration and has great potential to take place of polyanionic-type Li2MSiO4 (M = Mn, Fe, Co) cathode materials.

Lithium metal anode with high theoretical capacity is considered to be one of the most potential anode materials of the next generation. However, the growth of lithium dendrite seriously affects the application of lithium metal anode and the development of lithium metal batteries (LMBs). Herein, an ultrathin Li3N film modified separator to homogenize the lithium ions and protect the lithium metal anode was reported. Due to the intrinsic properties of Li3N, the functional separator possessed good thermal stability, mechanical properties and electrolyte wettability, and the homogenization of the lithium ion was realized without increasing the interface impedance. With this functional separator, the Li/Li symmetrical cell could achieve a long cycle with low overpotential for 1000 ​h at a current density of 1 ​mA ​cm−2. Furthermore, when the full battery was assembled with LiFePO4 and the discharge capacity could be maintained at 151 mAh g−1 after 400 cycles at 1 ​C. In addition, the full battery also showed good rate performance, and provided a high discharge capacity of 114 mAh g−1 at 5 ​C.

Ceramic-based composites are desirable lightweight materials for electromagnetic (EM) energy absorption. However, due to the lack of an effective electromagnetic wave attenuation mode, pure ceramics still face significant challenges in absorbing electromagnetic waves. It is still challenging to obtain advanced electromagnetic wave absorption (EMA) materials with low fillings, thin thickness, super absorption capacity, and effective absorption bandwidth (EAB) through clever microstructure design and appropriate multi-component strategy. Herein, a dielectric aluminosilicate/reduced graphene oxide (RGO) nanocomposite with different lithium content was constructed via a solvothermal sintering method. The microstructure and heterogeneous dielectric interface form perfect impedance matching, multiple polarization, coupling effects, and have excellent absorption performance. The absorbers display a minimal reflection loss (RLmin) of −51.95 dB by tuning the relaxation intensity, and the broadest covers all X band. In addition, the classic RCS simulation method to evaluate microwave absorption performance has practical application value in the field of radar stealth.

Solid-state lithium batteries using solid polymer electrolytes can improve the safety and energy density of batteries. Smoother lithium-ion channels are necessary for solid polymer electrolytes with high ionic conductivity. The porosity and channel structure of the polymer film affect the transfer of lithium ions. However, their controllable synthesis remains a big challenge. Here, we developed a simple synthesis approach toward wrinkled microporous polymer electrolytes by combining the amphoteric (water solubility and organic solubility) polymer in three polymer blends. The homogeneous blend solution spontaneously wrinkled to vertical fold channels as the solvent evaporated. Two minor polymers, poly(vinyl pyrrolidone) (PVP) and polyetherimide (PEI), formed close stacks, and Janus PVP was dispersed in the poly(vinylidene fluoride) (PVDF) matrix. The interfacial tensions between the three polymers were different, so stress was produced when they solidified. The solvent was evaporated to the top layer of the polymers when the temperature increased. The bottom layer wrinkled owing to the stress during solidification. The evaporation of the solvent generated micropores to form the lithium-ion channel. They helped Li+ transference and created a wrinkled microporous PVDF-based polymer electrolyte, which achieved an ionic conductivity of 5.1 × 10-4 S cm-1 and a lithium-ion transference number of 0.51 at room temperature. Meanwhile, the good flame retardancy and tensile strength of the polymer electrolyte film can improve the safety of the battery. At 0.5C and room temperature, the batteries with a LiFePO4 cathode and the wrinkled microporous LiTFSI/PEI/PVP/PVDF electrolyte reached a high discharge specific capacity of 122.1 mAh g-1 at the 100th cycle with a Coulombic efficiency of above 99%. The results of tensile and self-extinguishing tests show that the polymer electrolyte film has good safety application prospects.

Due to their good mechanical performances and high biocompatibility, all-ceramic materials are widely applied in clinics, especially in orthopedic and dental areas. However, the "hard" property negatively affects its integration with "soft" tissue, which greatly limits its application in soft tissue-related areas. For example, dental implant all-ceramic abutments should be well integrated with the surrounding gingival soft tissue to prevent the invasion of bacteria. Mimicking the gingival soft tissue and dentine integration progress, we applied the modified ion-exchange technology to "activate" the biological capacity of lithium disilicate glass-ceramics, via introducing OH

Recent advancements in quantum sensing have sparked transformative detection technologies with high sensitivity, precision, and spatial resolution. Owing to their atomic-level tunability, molecular qubits and ensembles thereof are promising candidates for sensing chemical analytes. Here, we show quantum sensing of lithium ions in solution at room temperature with an ensemble of organic radicals integrated in a microporous metal‒organic framework (MOF). The organic radicals exhibit electron spin coherence and microwave addressability at room temperature, thus behaving as qubits. The high surface area of the MOF promotes accessibility of the guest analytes to the organic qubits, enabling unambiguous identification of lithium ions and quantitative measurement of their concentration through relaxometric and hyperfine spectroscopic methods based on electron paramagnetic resonance (EPR) spectroscopy. The sensing principle presented in this work is applicable to other metal ions with nonzero nuclear spin.

One-dimensional nanobelt with inner nanopores has been considered as an ideal electrode material for electric energy storage. Herein iron manganese trioxide (FeMnO3) nanobelts have been prepared by a facile solvothermal approach. The phase, composition, structure and morphology of the as-synthesized sample are characterized by several techniques. Benefiting from the unique structure, the as-prepared FeMnO3 nanobelts achieve a superior lithium storage capacity with 635.7 mAh g−1 after 200 cycles, excellent cyclability and good kinetic properties, as well as a high specific capacitance of 209 F g−1 after 2000 cycles for supercapacitor. These results show a great application in large-scale energy storage.

Li3PO4 is known to demonstrate Li+ ionic conductivity, making it a good candidate for solid electrolytes in all-solid batteries. Understanding the crystal structure and its connection to Li+ diffusion is essential for further rational doping to improve the ionic transport mechanism. The purpose of this study is to investigate this mechanism using anisotropic displacement parameters (ADPs), nuclear density distribution and bond valence mapping. In situ neutron powder diffraction experiments have been performed using the high-resolution powder diffractometer ECHIDNA at the OPAL reactor, Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, NSW, Australia. The ADPs and nuclear density distribution were determined from the analysis of neutron diffraction data using the Rietveld method, whereas the bond valence map was calculated from the refined structure. The crystal structure remained unchanged as the temperature was increased (3, 100, 300 and 400 K). However, the ADPs show a greater increase in anisotropy in the a and b axes compared with the c axis, indicating the tendency of the ionic movement. By combining nuclear density distribution and bond valence mapping, the most likely lithium-ion diffusion in the crystal structure can be visualized.

To ameliorate the inherent issues of the huge volume expansion and low conductivity of vanadium tetrasulfide (VS4) as an anode material for lithium ion batteries, the structural design must be significantly effective. Therefore, we prepared various Mo-doped VS4 materials for the first time, and found that Mo impacted the VS4 structure. It was confirmed that Mo-doping not only could repair the sulfur vacancies of VS4, but also introduce the formation of local amorphous structure. Because the intrinsic sulfur vacancies in VS4 were repaired, the electrical conductivity of Mo-doped VS4 was improved and the Mo-doped VS4 electrode showed a superior rate performance. Moreover, the amorphous structure of Mo-doped VS4 provided more sites for the storage of lithium ions, more channels for the transportation of lithium ions, and a stable buffer to accommodate the volume change of VS4. Based on the synergistic effect between the repaired sulfur vacancies and introduction of local amorphous structure after Mo-doping, both the electrochemical performance and kinetics of Mo-VS4 electrode were enhanced distinctly.

Cerium dioxide nanocrystals embedded in porous carbon rod materials were used for sulfur storage and embedding. Polar cerium dioxide effectively adsorbed polysulfide and inhibited the shuttle effect. By calculating the diffusion coefficient of the lithium-ions, it was concluded that the porous carbon rod material with cerium oxide was beneficial for the rapid binding of lithium ions and sulfur.

We report the synthesis of three highly soluble metalorganic copolymers, TCP1–3, that were made from a one-pot complexation of iron(II) clathrochelate units that are interconnected by various thioether-containing contorted groups. TCP1–3 were converted into their poly(vinyl sulfone) derivatives OTCP1–3 quantitatively via the selective oxidation of the thioether moieties into their respective sulfones. All of the copolymers, TCP1–3 and OTCP1–3, underwent structural analysis by various techniques; namely, 1H- and 13C-nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The copolymers were tested as potent lithium ions adsorbents revealing a maximum adsorption (qm) value of 2.31 mg g−1 for OTCP2. Furthermore, this same copolymer was found to be a promising adsorbent of methylene blue (MEB); an isothermal adsorption study divulged that OTCP2’s uptake of MEB from an aqueous solution (following the Langmuir model) was, at maximum adsorption capacity, (qm) of 480.77 mg g−1; whereas the kinetic study divulged that the adsorption follows pseudo second-order kinetics with an equilibrium adsorption capacity (qe,cal) of 45.40 mg g−1.

Graphite nanosheets coated by LiF/SnO2 composites are designed to obtain a lithium ion anode material with excellent performance. LiF nanoparticles play a significant role in improving the electrochemical performance by inhibiting electrolyte decomposition and providing excess Li sources during cycling. The obtained LiF@SnO2@C electrode shows an outstanding capacity of 951.9 mAhg−1 at 0.2 Ag-1 after 370 cycles and excellent long cycling performance of 650.0 mAhg−1 at 1.0 Ag-1 after 930 cycles. First-principles calculations demonstrate that F-doped SnO2 (−2211.8 eV) has a lower free energy compared to SnO2 (−1937.4 eV), resulting in a robust composite architecture that gives rise to high cycling stability.

We present a non-perturbative classical treatment of the charge transfer and ionization processes in collisions between singly charged lithium ions with helium and nitrogen atomic targets. Single capture and single ionization total cross sections are calculated using a three-body classical trajectory Monte Carlo (CTMC) method in which the interaction between the collision partners is described by a Garvey-type model potential. The cross sections are evaluated for collision energies between 20 keV and 100 MeV. In particular, we found excellent agreement between our results and the available experimental data for the case of the single capture of He(1s) by Li+ ions. In addition, our CTMC results are in a reasonable agreement with the experimental results for collision energies higher than 200 keV for single capture of N(2p) atoms by Li+. Furthermore, we present single ionization cross sections for both collision systems.

The central focus of this research work is upon the synthesis of Lix-geopolymers (where x = 0.5 and 0.75) performed with the integration of lithium ions, in order to be used as cathode materials for lithium ions batteries. The obtained results presenting the requirements for these types of materials, demonstrate that Li-geopolymers could stand for a new alternative. The geopolymers were prepared at ambient temperature. The identification phase was carried out by powders X-ray diffraction, after calcination at various temperatures. The thermal stability was investigated by differential thermal analysis up to 1400 °C. With increase of lithium ions insertion, the temperature relative to the evaporation of P2O5 groups increased accompanied by a decrease in the mass loss relative to this phenomenon. The electrical measurements of both samples, were elaborated in the frequency range of 1–106 Hz and at a temperature range of 75–725 °C. After heating at 300 °C, the electrical conductivity values in the Li0.5-geopolymer material, were in the range of 10−6 S cm−1 and 10−4 S cm−1. By increasing lithium ions, the electrical conductivity values of the Li0.75-geopolymer sample, went from 10−7 to 10−5 S cm−1.

The investigation of the lithiation mechanism for anode materials plays a key role in the field of lithium-ion batteries. It can always offer a new approach to design and develop anode materials to improve their electrochemical performance. Therefore, we have studied the lithiation mechanism of PNb9O25 during cycling by the adoption of the in situ X-ray diffraction technique coupled with the analysis of a structure model in this work. The results present that PNb9O25 reacts with lithium at 1.62 and 1.11 V with a small lattice volume expansion of 10.69%. Meanwhile, based on the evolutions of the selected reflections ((130), (141), and (370)), the position of the inserted lithium ions in the lattice is revealed and thus, the diffusion channels of lithium ions can be inferred from it. According to this lithiation mechanism, we can find out some new avenues to design and develop the morphology of PNb9O25 or other niobate materials.

A green and natural biomass carbon with hollow structure was first reported derived from waste makeup cotton, which was prepared by facile pyrolysis and carbonisation in the nitrogen-filled vacuum tube furnace. Utilised as lithium-ion batteries (LIBs) anode materials, the hollow structure exhibits superior cycling and rate performance. At the current density of 100 mA g−1, it demonstrates a reversible capacity of 340 mAh g−1 with the Coulombic efficiency of 58.8%, and the reversible capacity gradually increases to 450 mAh g−1 at 300 cycles, displaying long cycling stability. Even at a higher current density of 500 mA g−1, the capacity can be maintained around 245 mAh g−1 after 150 cycles. Moreover, the hollow carbon exhibits excellent rate capability (222 mAh g−1 at an ultrahigh rate of 2000 mA g−1). This enhanced property can be attributed to its special hollow structure, which could provide fast lithium ions and electrons transfer path to facilitate the electrochemical reaction. The authors believe this work could help to design new carbon materials with green and environmental protection as anode materials for LIBs.

A new spinel Li2Ni0.5Mn1.5O4 (LNMO) cathode reported in our previous work displays high initial specific capacity (260.4 mAh g−1) and good coulombic efficiency (92.2%), but suffers from low capacity retention of 80.2% after 50 cycles. In this paper, Li2O-0.2B2O3-1.8SiO2 (LBSO) glass phase surface modification is adopted to promote the electrochemical performance of LNMO. LBSO layer coated on the surface of LNMO cathode, as confirmed by SEM and HRTEM observation, can effectively prevent the cathode from dissolving in the electrolyte, therefore suppresses the increase in resistance and the degradation in Li-ions diffusion. Consequently, the electrochemical properties of the surface modified cathode material are improved. The initial specific capacity of 0.3 wt% LBSO coated LNMO is kept as 263 mAh g−1 with coulombic efficiency of 95%. Notably, the capacity retention after 100 cycles is improved from 69% to 83% by a comparison between the pristine and coated samples. Moreover, the coated cathode exhibits good rate performance, giving high specific capacity of 142 mAh g−1 even at a current density of 5C. All the results presented above suggest high potential for the material as candidate cathode for high energy density batteries.