Boosting Reactive Oxygen Species Formation Over Pd and VOδ Co-Modified TiO2 for Methane Oxidation into Valuable Oxygenates.

Direct photocatalytic methane oxidation into value-added products provides a promising strategy for methane utilization. However, the inefficient generation of reactive oxygen species (ROS) partly limits the activation of CH4 . Herein, it is reported that Pd and VOδ co-modified TiO2 enables direct and selective methane oxidation into liquid oxygenates in the presence of O2 and H2 . Due to the extra ROS production from the in situ formed H2 O2 , a highly improved yield rate of 5014 µmol g-1  h-1 for liquid oxygenates with a selectivity of 89.3% is achieved over the optimized Pd0.5 V0.2 -TiO2 catalyst at ambient temperature, which is much better than those (2682 µmol g-1  h-1 , 77.8%) without H2 . Detailed investigations also demonstrate the synergistic effect between Pd and VOδ species for enhancing the charge carrier separation and transfer, as well as improving the catalytic activity for O2 reduction and H2 O2 production.

Synergetic Dual-Additive Electrolyte Enables Highly Stable Performance in Sodium Metal Batteries.

Sodium (Na)-metal batteries (SMBs) are considered one of the most promising candidates for the large-scale energy storage market owing to their high theoretical capacity (1,166 mAh g-1) and the abundance of Na raw material. However, the limited stability of electrolytes still hindered the application of SMBs. Herein, sulfolane (Sul) and vinylene carbonate (VC) are identified as effective dual additives that can largely stabilize propylene carbonate (PC)-based electrolytes, prevent dendrite growth, and extend the cycle life of SMBs. The cycling stability of the Na/NaNi0.68Mn0.22Co0.1O2 (NaNMC) cell with this dual-additive electrolyte is remarkably enhanced, with a capacity retention of 94% and a Coulombic efficiency (CE) of 99.9% over 600 cycles at a 5 C (750 mA g-1) rate. The superior cycling performance of the cells can be attributed to the homogenous, dense, and thin hybrid solid electrolyte interphase consisting of F- and S-containing species on the surface of both the Na metal anode and the NaNMC cathode by adding dual additives. Such unique interphases can effectively facilitate Na-ion transport kinetics and avoid electrolyte depletion during repeated cycling at a very high rate of 5 C. This electrolyte design is believed to result in further improvements in the performance of SMBs.

Localized high-concentration electrolytes get more localized through micelle-like structures.

Liquid electrolytes in batteries are typically treated as macroscopically homogeneous ionic transport media despite having a complex chemical composition and atomistic solvation structures, leaving a knowledge gap of the microstructural characteristics. Here, we reveal a unique micelle-like structure in a localized high-concentration electrolyte, in which the solvent acts as a surfactant between an insoluble salt in a diluent. The miscibility of the solvent with the diluent and simultaneous solubility of the salt results in a micelle-like structure with a smeared interface and an increased salt concentration at the centre of the salt-solvent clusters that extends the salt solubility. These intermingling miscibility effects have temperature dependencies, wherein a typical localized high-concentration electrolyte peaks in localized cluster salt concentration near room temperature and is used to form a stable solid-electrolyte interphase on a Li metal anode. These findings serve as a guide to predicting a stable ternary phase diagram and connecting the electrolyte microstructure with electrolyte formulation and formation protocols of solid-electrolyte interphases for enhanced battery cyclability.

Effects of fluorinated solvents on electrolyte solvation structures and electrode/electrolyte interphases for lithium metal batteries.

Electrolyte is very critical to the performance of the high-voltage lithium (Li) metal battery (LMB), which is one of the most attractive candidates for the next-generation high-density energy-storage systems. Electrolyte formulation and structure determine the physical properties of the electrolytes and their interfacial chemistries on the electrode surfaces. Localized high-concentration electrolytes (LHCEs) outperform state-of-the-art carbonate electrolytes in many aspects in LMBs due to their unique solvation structures. Types of fluorinated cosolvents used in LHCEs are investigated here in searching for the most suitable diluent for high-concentration electrolytes (HCEs). Nonsolvating solvents (including fluorinated ethers, fluorinated borate, and fluorinated orthoformate) added in HCEs enable the formation of LHCEs with high-concentration solvation structures. However, low-solvating fluorinated carbonate will coordinate with Li+ ions and form a second solvation shell or a pseudo-LHCE which diminishes the benefits of LHCE. In addition, it is evident that the diluent has significant influence on the electrode/electrolyte interphases (EEIs) beyond retaining the high-concentration solvation structures. Diluent molecules surrounding the high-concentration clusters could accelerate or decelerate the anion decomposition through coparticipation of diluent decomposition in the EEI formation. The varied interphase features lead to significantly different battery performance. This study points out the importance of diluents and their synergetic effects with the conductive salt and the solvating solvent in designing LHCEs. These systematic comparisons and fundamental insights into LHCEs using different types of fluorinated solvents can guide further development of advanced electrolytes for high-voltage LMBs.

In Situ Visualization of the Pinning Effect of Planar Defects on Li Ion Insertion.

Longevity of Li ion batteries strongly depends on the interaction of transporting Li ions in electrode crystals with defects. However, detailed interactions between the Li ion flux and structural defects in the host crystal remain obscure due to the transient nature of such interactions. Here, by in situ transmission electron microscopy and density function theory calculations, we reveal how the diffusion pathways and transport kinetics of a Li ion can be affected by planar defects in a tungsten trioxide lattice. We uncover that changes in charge distribution and lattice spacing along the planar defects disrupt the continuity of ion conduction channels and dramatically increase the energy barrier of Li diffusion, thus, arresting Li ions at the defect sites and twisting the lithiation front. The atomic-scale understanding holds critical implications for rational interface design in solid-state batteries and solid oxide fuel cells.

Role of inner solvation sheath within salt-solvent complexes in tailoring electrode/electrolyte interphases for lithium metal batteries.

Functional electrolyte is the key to stabilize the highly reductive lithium (Li) metal anode and the high-voltage cathode for long-life, high-energy-density rechargeable Li metal batteries (LMBs). However, fundamental mechanisms on the interactions between reactive electrodes and electrolytes are still not well understood. Recently localized high-concentration electrolytes (LHCEs) are emerging as a promising electrolyte design strategy for LMBs. Here, we use LHCEs as an ideal platform to investigate the fundamental correlation between the reactive characteristics of the inner solvation sheath on electrode surfaces due to their unique solvation structures. The effects of a series of LHCEs with model electrolyte solvents (carbonate, sulfone, phosphate, and ether) on the stability of high-voltage LMBs are systematically studied. The stabilities of electrodes in different LHCEs indicate the intrinsic synergistic effects between the salt and the solvent when they coexist on electrode surfaces. Experimental and theoretical analyses reveal an intriguing general rule that the strong interactions between the salt and the solvent in the inner solvation sheath promote their intermolecular proton/charge transfer reactions, which dictates the properties of the electrode/electrolyte interphases and thus the battery performances.

Diversity of Fungal Endophytes in American Ginseng Seeds.

Seeds play a critical role in the production of American ginseng. Seeds are also one of the most important media for the long-distant dissemination and the crucial way for pathogen survival. Figuring out the pathogens carried by seeds is the basis for effective management of seedborne diseases. In this paper, we tested the fungi carried by the seeds of American ginseng from the main production areas of China using incubation and highly throughput sequencing methods. The seed-carried rates of fungi in Liuba, Fusong, Rongcheng, and Wendeng were 100, 93.8, 75.2, and 45.7%, respectively. Sixty-seven fungal species, which belonged to 28 genera, were isolated from the seeds. Eleven pathogens were identified from the seed samples. Among the pathogens, Fusarium spp. were found in all of the seed samples. The relative abundance of Fusarium spp. in the kernel was higher than that in the shell. Alpha index showed that the fungal diversity between seed shell and kernel differed significantly. Nonmetric multidimensional scaling analysis revealed that the samples from different provinces and between seed shell and kernel were distinctly separated. The inhibition rates of four fungicides to seed-carried fungi of American ginseng were 71.83% for Tebuconazole SC, 46.67% for Azoxystrobin SC, 46.08% for Fludioxonil WP, and 11.11% for Phenamacril SC. Fludioxonil, a conventional seed treatment agent, showed a low inhibitory effect on seed-carried fungi of American ginseng.

Acidic Media Impedes Tandem Catalysis Reaction Pathways in Electrochemical CO2 Reduction.

Electrochemical CO2 reduction (CO2 R) in acidic media with Cu-based catalysts tends to suffer from lowered selectivity towards multicarbon products. This could in principle be mitigated using tandem catalysis, whereby the *CO coverage on Cu is increased by introducing a CO generating catalyst (e.g. Ag) in close proximity. Although this has seen significant success in neutral/alkaline media, here we report that such a strategy becomes impeded in acidic electrolyte. This was investigated through the co-reduction of 13 CO2 /12 CO mixtures using a series of Cu and CuAg catalysts. These experiments provide strong evidence for the occurrence of tandem catalysis in neutral media and its curtailment under acidic conditions. Density functional theory simulations suggest that the presence of H3 O+ weakens the *CO binding energy of Cu, preventing effective utilization of tandem-supplied CO. Our findings also provide other unanticipated insights into the tandem catalysis reaction pathway and important design considerations for effective CO2 R in acidic media.

Lithium Metal Anodes with Nonaqueous Electrolytes.

High-energy rechargeable lithium (Li) metal batteries (LMBs) with Li metal anode (LMA) were first developed in the 1970s, but their practical applications have been hindered by the safety and low-efficiency concerns related to LMA. Recently, a worldwide effort on LMA-based rechargeable LMBs has been revived to replace graphite-based, Li-ion batteries because of the much higher energy density that can be achieved with LMBs. This review focuses on the recent progress on the stabilization of LMA with nonaqueous electrolytes and reveals the fundamental mechanisms behind this improved stability. Various strategies that can enhance the stability of LMA in practical conditions and perspectives on the future development of LMA are also discussed. These strategies include the use of novel electrolytes such as superconcentrated electrolytes, localized high-concentration electrolytes, and highly fluorinated electrolytes, surface coatings that can form a solid electrolyte interphase with a high interfacial energy and self-healing capabilities, development of "anode-free" Li batteries to minimize the interaction between LMA and electrolyte, approaches to enable operation of LMA in practical conditions, etc. Combination of these strategies ultimately will lead us closer to the large-scale application of LMBs which often is called the "Holy Grail" of energy storage systems.

Indocyanine green fluorescence imaging improves the assessment of blood supply of interposition jejunum.

OBJECTIVES: The blood supply of the transposed jejunum was assessed by ICG fluorescence imaging in jejunal interposition, and the correlation with anastomotic leakage or transposed jejunal necrosis was analyzed, aim to explore the value of the application ICG fluorescence imaging technology. METHODS: 84 esophageal reconstructions with jejunal interposition without supercharging were retrospectively analyzed. Intraoperatively, the blood supply of transposed jejunal was observed using ICG fluorescence endoscopy. ROC curve of T1/2 was constructed to calculate the corresponding T1/2max value of the region where the transposed jejunal want to be anastomosed with esophageal stump, the relationship between T1/2max value and anastomotic leakage or transposed jejunal necrosis was analyzed. RESULTS: The occurrence of anastomotic leakage and transposed jejunal necrosis was 9.5%, In the ROC curve, the maximum value of the Youden index was 0.691, the T1/2max value was 5.35 s. When T1/2max value > 5.35 s correspondingly, the probability of anastomotic leakage or transposition jejunal necrosis was 33.3% (7/21); when T1/2max value ≤ 5.35 s, the probability of anastomotic leakage or transposition jejunal necrosis was 1.6% (1/63). The difference between the two groups was statistically significant (P < 0.05). CONCLUSION: ICG fluorescent imaging can effectively assess the blood supply of transposed jejunum. When T1/2max > 5.35, the possibility of the incidence rate of anastomotic leakage or transposed jejunum necrosis increases, this will remind the operators to take corresponding remedial measures during operation.

Vacancy-Mediated Hydrogen Spillover Improving Hydrogen Storage Properties and Air Stability of Metal Hydrides.

Hydrogen storage in metal hydrides is a promising solution for sustainable and clean energy carriers. Although Mg-based metal hydrides are considered as potential hydrogen storage media, severe surface passivation has limited their industrial application. In this study, a simple, cheap, and efficient method is proposed to produce highly reactive and air-stable bulk Mg-Ni-based hydrides by rapid treatment with water for 3 min. The nickel-decorated Mg(OH)2 nanosheets formed in situ during hydrolysis can provide a pathway for hydrogen desorption via vacancy-mediated hydrogen spillover, as revealed by density functional theory calculations, thereby significantly decreasing the peak dehydrogenation temperature by 108.2 °C. Moreover, water-activated hydrides can be stored under ambient conditions without surface decay and activity loss, exhibiting excellent air stability, which can be attributed to the chemical stability of the surface layer. The results provide alternative insights into the design of highly active, air-stable metal hydrides with low cost and promote the industrial application of hydrogen energy.

Glassy Li metal anode for high-performance rechargeable Li batteries.

Lithium metal has been considered an ideal anode for high-energy rechargeable Li batteries, although its nucleation and growth process remains mysterious, especially at the nanoscale. Here, cryogenic transmission electron microscopy was used to reveal the evolving nanostructure of Li metal deposits at various transient states in the nucleation and growth process, in which a disorder-order phase transition was observed as a function of current density and deposition time. The atomic interaction over wide spatial and temporal scales was depicted by reactive molecular dynamics simulations to assist in understanding the kinetics. Compared to crystalline Li, glassy Li outperforms in electrochemical reversibility, and it has a desired structure for high-energy rechargeable Li batteries. Our findings correlate the crystallinity of the nuclei with the subsequent growth of the nanostructure and morphology, and provide strategies to control and shape the mesostructure of Li metal to achieve high performance in rechargeable Li batteries.

Inspecting the structural characteristics of chiral drug penicillamine under different pH conditions using Raman optical activity spectroscopy and DFT calculations.

The investigation of the structural characteristics of chiral drugs in physiological environments is a challenging research topic, which may lead to a better understanding of how the drugs work. Raman optical activity (ROA) spectroscopy in combination with density functional theory (DFT) calculations was exploited to inspect the structural changes in penicillamine under different acid-base states in aqueous solutions. The B3LYP/aug-cc-PVDZ method was employed and the implicit solvation model density (SMD) was considered for describing the solvation effect in H2O. The conformations of penicillamine varied with pH, but penicillamine was liable to stabilize in the form of the PC conformation (the sulfur atom is in a trans orientation with respect to carboxylate) in most cases for both D- and L-isomers. The relationship between the conformations of penicillamine and the ROA peaks, as well as peak assignments, were comprehensively studied and elucidated. In the fingerprint region, two ROA couplets and one ROA triplet with different patterns were recognized. The intensity, sign and frequency of the corresponding peaks also changed with varying pH. Deuteration was carried out to identify the vibrational modes, and the ROA peaks of the deuterated amino group in particular are sensitive to change in the ambient environment. The results are expected not only to serve as a reference for the interpretation of the ROA spectra of penicillamine and other chiral drugs with analogous structures but also to evaluate the structural changes of chiral molecules in physiological environments, which will form the basis of further exploration of the effects of structural characteristics on the pharmacological and toxicological properties of chiral drugs.

American Ginseng Root Rot Caused by Fusarium redolens in China.

American ginseng (Panax quinquefolium L.) originating from North America is one of important herbal medicine and economic crops . With the increasing market demand, China has become the third producer and the largest consumer country of American ginseng. However, continuous cropping obstacle has become the most serious problem for the production of American ginseng, and the continuous cropping of soils usually lead to accumulations of root fungal pathogens and increasing plant disease occurrence (1), root rot caused by the notorious soil-borne pathogenic fungi, Fusarium spp., results in a significant reduction of yield and quality of American ginseng. Investigation of American ginseng root rot was carried out in Liuba county, Shaanxi province, China from 2017 to 2019. About 20% of over 3-year-old American ginseng showed varied root rot symptoms in newly reclaimed fields, and more than 70% in continuous American ginseng planting fields. Among these root rot diseases, we found one kind of disease which shows symptoms of red leaves in initial stage and yellow or yellow brown lesions at the reed heads or taproots. The lesions mainly appear on the root surface; however, the vascular tissue has no discoloration. The aboveground parts become wilted and died, and the whole root appears dark brown rots. Fifteen Fusarium spp. isolates were obtained by cutting diseased rot roots into 5 × 5 mm2 pieces, disinfecting in 70% ethanol for 1 min, rinsing 2 ~ 3 times in sterile water for 1 min and isolating on PDA medium including 50 µg/mL streptomycin sulfate. All the isolates have identical morphological characteristics. The colony was white with curved and uplifted aerial hyphae in central region. The colony diameter was 48 ~51 mm after 6 days at room temperature. Microconidia were oval to cylindrical shape with 0 to 1 septa, ranged from 6.24 to10.09 µm long; the macroconidia were fusiform to conical with a hooked apical cell and a foot-shaped basal cell, usually 3 to 5 septa, ranged from 31.45 to 42.52 µm long. The chlamydospores were not found under our culture condition. Preliminary data analysis showed that the morphological characteristics of these isolates were consistent with the descriptions of Fusarium redolens (2). To clarify the fungus in the taxonomy , the rDNA internal transcribed spacer (ITS), the translation elongation factor 1 alpha (TEF1-α) and the RNA polymerase II subunit 1 (RPB1) fragments of two randomly selected isolates were amplified and sequenced. The sequences of the corresponding fragments of the two isolates were identical. The blast results in the GenBank and FUSARIUM-ID databases show the isolates belong to F. redolens (3). Previous study indicated F. redolens has an indistinguishable relative, F. hostae (4). Although the ITS sequence (MW331695) cannot provide enough information to distinguish them, the phylogenetic tree combined the sequence of TEF1-α (tempID: 2407237 ) and RPB1 (tempID: 2407229) clearly showed that the isolates are F. redolens. (Fig) The pathogenicity of a representative isolate, YP04, was tested on ginseng taproot by in vivo inoculation experiments with three replications. The taproot surface of 2-year-old healthy ginseng was washed and disinfested with 75% alcohol for 1 min and rinsed with sterile water, and dried. The surface of taproot was injured with sterilized steel needles and immersed in 1 × 106 /ml spore suspension (sterile water for control plants) for 30 min. The treatment and control plants were transplanted in 20 cm diameter flowerpots filled with sterilized humus and cultured in a greenhouse at 18-23°C. Six days after transplanting, the leaves began to turn red. The cortex of ginseng taproot showed yellow brown lesions and the vascular tissue turn to light yellow. Fifteen days after transplanting, the aboveground parts of treatment plants began to wilting and the taproots showed serious rots. no taproot rot was observed in the controls. The pathogen was re-isolated from the diseased taproots successfully. To our knowledge, this is the first report of F. redolens causing root rot of American ginseng in China.

Atomic to Nanoscale Origin of Vinylene Carbonate Enhanced Cycling Stability of Lithium Metal Anode Revealed by Cryo-Transmission Electron Microscopy.

Batteries using lithium (Li) metal as the anode are considered promising energy storage systems because of their high specific energy densities. The crucial bottlenecks for Li metal anode are Li dendrites growth and side reactions with electrolyte inducing safety concern, low Coulombic efficiency (CE), and short cycle life. Vinylene carbonate (VC), as an effective electrolyte additive in Li-ion batteries, has been noticed to significantly enhance the CE, whereas the origin of such an additive remains unclear. Here we use cryogenic transmission electron microscopy imaging combing with energy dispersive X-ray spectroscopy elemental and electron energy loss spectroscopy electronic structure analyses to reveal the role of the VC additive. We discovered that the electrochemically deposited Li metal (EDLi) in the VC-containing electrolyte is slightly oxidized with the solid electrolyte interphase (SEI) being a nanoscale mosaic-like structure comprised of organic species, Li2O and Li2CO3, whereas the EDLi formed in the VC-free electrolyte is featured by a combination of fully oxidized Li with Li2O SEI layer and pure Li metal with multilayer nanostructured SEI. These results highlight the possible tuning of crucial structural and chemical features of EDLi and SEI through additives and consequently direct correlation with electrochemical performance, providing valuable guidelines to rational selection, design, and synthesis of additives for new battery chemistries.

Optimization of Magnesium-Doped Lithium Metal Anode for High Performance Lithium Metal Batteries through Modeling and Experiment.

Lithium (Li)-magnesium (Mg) alloy with limited Mg amount, which can also be called Mg-doped Li (Li-Mg), has been considered as a potential alternative anode for high energy density rechargeable Li metal batteries. However, the optimum doping-content of Mg in Li-Mg anode and the mechanism of the improved performance are not well understood. Herein, density functional theory (DFT) calculations are used to investigate the effect of Mg amount in Li-Mg anode. The Li-Mg with about 5 wt. % Mg (abbreviated as Li-Mg5) has the lowest absorption energy of Li, thus all the surface area can be "controlled" by Mg atoms, leading to the smooth and continuous deposition of Li on the surface around the Mg center. A localized high concentration electrolyte enables Li-Mg5 to exhibit the best cycling stability in Li metal batteries with high-loading cathode and lean electrolyte under 4.4 V high-voltage, which is approaching the demand of practical application. This electrolyte also helps generate an inorganic-rich solid electrolyte interphase, which leads to smooth, compact and less corrosion layer on the Li-Mg5 surface. Both theoretical simulations and experimental results prove that Li-Mg5 has optimum Mg content and gives best battery cycling performance.

Catalytic effect of sandwich-like Ti3C2/TiO2(A)-C on hydrogen storage performance of MgH2.

A sandwich-like Ti3C2/TiO2(A)-C prepared through a facile gas-solid method was doped into MgH2 by ball milling. Ti3C2/TiO2(A)-C shows a far superior catalytic effect on the hydrogen storage of MgH2 than individual Ti3C2 or TiO2(A)-C, assigning as a synergistic catalysis between Ti3C2 and TiO2(A)-C. For example, the peak dehydrogenation temperature of MgH2-5 wt% Ti3C2/TiO2(A)-C is reduced to 308 °C, much lower than that of MgH2-5 wt% Ti3C2 (340 °C) or MgH2-5 wt% TiO2(A)-C (356 °C). After dehydrogenation, the dehydrogenated MgH2-5 wt% Ti3C2/TiO2(A)-C can uptake approximately 4 wt% of hydrogen within 800 s at 125 °C, while for the dehydrogenated MgH2-5 wt% Ti3C2 and MgH2-5 wt% TiO2(A)-C, only 3 wt% and 2.65 wt% hydrogen content can be obtained, respectively. Besides this, MgH2-5 wt% Ti3C2/TiO2(A)-C exhibits the lowest apparent activation energies (42.32 kJ mol-1 H2 for the hydrogen absorption and 77.69 kJ mol-1 H2 for the hydrogen desorption), which can explain the excellent hydrogen ab/desorption kinetic properties. The synergetic effects between the special layered structure and multiple valence titanium compounds (Ti4+, Ti3+, Ti2+, Ti0) verified by the x-ray photoelectron spectroscopy results are responsible for the catalytic mechanism on the hydrogen storage of MgH2. This study also supplies innovative insights into designing high efficiency MXene derivative catalysts in hydrogen storage.

Three-dimensional printing technology for localised thoracoscopic segmental resection for lung cancer: a quasi-randomised clinical trial.

BACKGROUND: Three-dimensional (3D) computed tomography (CT) reconstruction technology has gained attention owing to its potential in locating ground glass nodules in the lung. The 3D printing technology additionally allows the visualisation of the surrounding anatomical structure and variations. However, the clinical utility of these techniques is unknown. This study aimed to establish a lung tumour and an anatomical lung model using 3D printing and 3D chest CT reconstruction and to evaluate the clinical potential of 3D printing technology in uniportal video-assisted thoracoscopic segmentectomy. METHODS: Eighty-nine patients with ground glass nodules who underwent uniportal video-assisted thoracoscopic segmentectomy were classified into the following groups: group A, lung models for pre-positioning and simulated surgery that were performed with 3D chest CT reconstruction and 3D printing, and group B, patients who underwent chest CT scans with image enhancement for 3D reconstruction. The differences in the surgery approach transfer rate, surgical method conversion rate, operative time, intraoperative blood loss, and postoperative complication rate were compared between the two groups. RESULTS: Between groups A and B, there were significant differences in the approach transfer rate (0% vs.10.5%, p = 0.030), operative time (2.07 ± 0.24 h vs. 2.55 ± 0.41 h, p < 0.001), intraoperative blood loss volume (43.25 ± 13.63 mL vs. 96.68 ± 32.82 mL, p < 0.001) and the rate of surgical method conversion to lobectomy (0% vs. 10.5%, p < 0.030). In contrast, there was an insignificant difference in the postoperative complication rate between groups A and B (3.9% vs. 13.2%, p = 0.132). CONCLUSIONS: 3D printing technology facilitates a more accurate location of nodules by surgeons, as it is based on two-dimensional and 3D image-based findings, and therefore, it can improve surgical accuracy and safety. This technique is worth applying in clinical practice.

Atomic Resolution Structural and Chemical Imaging Revealing the Sequential Migration of Ni, Co, and Mn upon the Battery Cycling of Layered Cathode.

Layered lithium transition metal oxides (LTMO) are promising candidate cathode materials for next-generation high-energy density lithium ion battery. The challenge for using this category of cathode is the capacity and voltage fading, which is believed to be associated with the layered structure disordering, a process that is initiated from the surface or solid-electrolyte interface and facilitated by transition metal (TM) reduction and oxygen vacancy formation. However, the atomic level dynamic mechanism of such a layered structure disordering is still not fully clear. In this work, utilizing atomic resolution electron energy loss spectroscopy (EELS), we map, for the first time at atomic scale, the spatial evolution of Ni, Co and Mn in a cycled LiNi1/3Mn1/3Co1/3O2 layered cathode. In combination with atomic level structural imaging, we discovered the direct correlation of TM ions migration behavior with lattice disordering, featuring the residing of TM ions in the tetrahedral site and a sequential migration of Ni, Co, and Mn upon the increased lattice disordering of the layered structure. This work highlights that Ni ions, though acting as the dominant redox species in many LTMO, are labile to migrate to cause lattice disordering upon battery cycling, while the Mn ions are more stable as compared with Ni and Co and can act as pillar to stabilize layered structure. Direct visualization of the behavior of TM ions during the battery cycling provides insight for designing of cathode with high structural stability and correspondingly a superior performance.