Lithium-excess disordered rock-salt(DRX)materials have emerged as promising cathode candidates owing to their high capacity and energy density.Although short-range ordering(SRO)has been reported in DRX material Li_1.16Ti_0.37Ni_0.37Nb_0.10O₂,quantitative analysis of its real-space structural origin remains scarce.Therefore,this paper mainly characterized Li_1.1Mn_0.8Ti_0.1O_1.9F_0.1using spherical aberration-corrected transmission electron microscopy(TEM).Through a series of tilting experiments,the distribution of diffuse scattering bands was identified.Quantitative analysis of atomic-resolution images confirmed that these diffuse bands in electron diffraction arised mainly from intensity variations within the transition-metal(TM)cation columns,indicating that SRO originated from the specific distribution of cations.For comparison,Li_1.05Mn_0.85Ti_0.1O₂without F was also designed,and it was found that the ordering was significantly enhanced.These results suggested that fluorination might correlate with the improved electrochemical performance via its influence on SRO.The arrangement of disordered cations and the concentration of vacancies directly affected Li percolation pathways and consequently the electrochemical behavior of DRX anodes.Li_1.05Mn_0.85Ti_0.1O₂(LMTO)and Li_1.1Mn_0.8Ti_0.1O_1.9F_0.1(LMTOF)were synthesized by weighing stoichiometric amounts of Li₂CO₃,Mn₂O₃,TiO₂,and LiF,and mixing them in a ZrO₂ball-milling jar.The mixture was ball-milled at 600 r·min^-1for 6 h,then heated in a tube furnace under an inert atmosphere at a rate of 3℃·min^-1to 1100℃,held for 20 min,and cooled naturally to room temperature.To avoid Ga⁺beam damage during focused ion beam(FIB)sampling,atomic-resolution images were obtained from particles directly dispersed onto microgrids via ultrasonication.For TEM observation,powder samples were ultrasonically dispersed in dimethyl carbonate and deposited onto carbon films or grids.Selected-area diffraction patterns were acquired using a JEOL JEM-F200 thermal field-emission TEM,with the beam positioned at thin particle edges.High-angle annular dark-field scanning TEM(HAADF-STEM)images were obtained using a JEOL JEM-ARM200F cold field-emission microscope equipped with a spherical-aberration corrector,operated at 200 kV with a collection angle of 50~200 mrad.Fast Fourier transform(FFT)patterns showing clear diffuse bands were processed using Calatom software,involving filtering,Fourier transform,and inverse Fourier transform of HAADF-STEM images.Periodic structures yield sharp Bragg spots in Fourier space,while diffuse scattering was distributed throughout reciprocal space.To extract triple-periodic structural information,appropriate filtering windows were applied around major Bragg reflections before inverse Fourier transformation.Calatom analysis showed that diffuse bands in experimental FFT patterns correspond to variations in TM column intensity rather than positional disorder.In Li_1.1Mn_0.8Ti_0.1O_1.9F_0.1,SRO primarily resulted from intensity variations of Ti/Mn cation columns,likely influenced by Li site occupancy.Filtering that retains superstructure information in FFT led to periodic strong-weak intensity modulation of atomic columns,whereas filtering only the main reflections yield homogeneous intensity.Since HAADF intensity scales with atomic number,and only Ti and Mn were visible along[001]zone axis,the observed superstructure in Li_1.1Mn_0.8Ti_0.1O₂could be attributed to SRO similar to that in the fluorinated sample.This implied that the superstructure was related to TM column intensity variations associated with ordered Li occupancy.In Li_1.1Mn_0.8Ti_0.1O₂,enhanced ordering was observed,with elongated superstructure reflections appearing at wave vectors q₁=a^*-0.5b^*,q₂=0.5a^*-0.5b^*,and q₃=0.5a^*-b^*,indicating cation ordering.These results suggested that F-doping improved capacity retention by reducing cation(including Li)ordering.The SRO of TM cations within the disordered lattice significantly influenced Li percolation channels during cycling.Therefore,understanding DRX structures at the atomic scale could guide the design and optimization of high-performance Li-excess disordered rock-salt cathodes.

Persistent luminescence nanoparticles(PLNPs)are distinctive optical materials that possess the remarkable property of emitting afterglow luminescence once excitation has ceased.Thanks to the absence of in-situ excitation,PLNPs are capable of effectively eliminating interference caused by autofluorescence and light scattering.Moreover,PLNPs have received significant attention and have been widely used as optical probes in bioimaging and biosensing applications.This is due to several factors,including their nano-effects,efficient cell penetration ability,and superior biocompatibility.In this paper,we provide a thorough review of the controlled synthesis strategies and luminescence mechanisms of PLNPs,and the progress made in their applications in biomedical fields in recent years.We summarize and analyze the latest research advancements in PLNPs-based biochemical sensing,bioimaging,and image-guided therapeutics.We also discuss the challenges currently faced by PLNP-based biomedicine,while keeping an eye on the future direction of development.Our aim is to facilitate and promote the diversified applications of PLNPs in biomedicine.

s a promising alternative to sluggish Li2CO3-based Li-CO2 electrochemistry, Li2C2O4 offers a favorable 2e− discharge pathway, yet its selective formation and reversible decomposition remain debated. Herein, we propose a nonmetal-metal synergistic catalyst—B-Ti coregulated layered transition metal boride Ti18B18O9/graphene (B-Ti/TiBOG)—to enable efficient CO2-to-Li2C2O4 conversion via frontier orbital engineering (FOE). Density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations reveal that the low electronegativity of B (O > N > C > B) induces asymmetric Ti coordination, driving strong B 2p and Ti 3d orbital hybridization near the Fermi level, and better structural stability, outperforming C/N/O-Ti analogs. Interestingly, this unique FO alignment activates CO2 by populating its antibonding orbitals through a bidirectional “acceptance-feedback” mechanism to enhance CO2 adsorption (from −0.19 to −1.05 eV). The B-Ti synergy selectively stabilizes Li2C2O4 nucleation while kinetically suppressing its conversion to Li2CO3 (barrier > 0.68 eV). Consequently, the hybrid B-Ti/TiBOG catalyst achieves exceptional bifunctionality, yielding a minimal total overpotential (0.75 V) for CO2-to-Li2C2O4 cycling—maintained in the tetraethylene glycol dimethyl ether (TEGDME) solvent environments. This work highlights electronegativity-driven FOE in B-Ti diatomic synergy as key for rechargeable Li-CO2 batteries.

This study examines the feasibility of integrating advanced battery technologies into electrified propulsion systems for aviation as a pathway toward carbon emission reduction. While the successful deployment of battery-powered electric vehicles (EVs) has demonstrated the potential of electrification in sustainable mobility, the aviation sector presents distinct technical and operational challenges that require specialized engineering solutions. This work provides a comprehensive review of recent industrial developments and scholarly literature to evaluate the technological, environmental, and economic viability of electrified aircraft. Key performance limitations and energy density constraints associated with current lithium-based batteries are analyzed, along with their safety considerations and life cycle sustainability. In addition, the operational costs of battery-powered and hybrid-electric aircraft concepts are compared with those of conventional jet fuel-based systems. Recent progress in hybrid-electric propulsion architectures, emerging battery chemistries such as lithium-metal and lithium-sulfur, and future directions for propulsion system integration are also discussed. Overall, this study offers insights into sustainable aviation strategies and identifies critical research directions to accelerate the transition toward carbon-neutral flight.