Correlating concerted cations with oxygen redox in rechargeable batteries.

Rechargeable batteries currently power much of our world, but with the increased demand for electric vehicles (EVs) capable of traveling hundreds of miles on a single charge, new paradigms are necessary for overcoming the limits of energy density, particularly in rechargeable batteries. The emergence of reversible anionic redox reactions presents a promising direction toward achieving this goal; however this process has both positive and negative effects on battery performance. While it often leads to higher capacity, anionic redox also causes several unfavorable effects such as voltage fade, voltage hysteresis, sluggish kinetics, and oxygen loss. However, the introduction of cations with topological chemistry tendencies has created an efficient pathway for achieving long-term oxygen redox with improved kinetics. The cations serve as pillars in the crystal structure and meanwhile can interact with oxygen in ways that affect the oxygen redox process through their impact on the electronic structure. This review delves into a detailed examination of the fundamental physical and chemical characteristics of oxygen redox and elucidates the crucial role that cations play in this process at the atomic and electronic scales. Furthermore, we present a systematic summary of polycationic systems, with an emphasis on their electrochemical performance, in order to provide perspectives on the development of next-generation cathode materials.

[Clinical characteristics of 267 children with eosinophilic gastrointestinal disease: a multicenter study]. / 267ä¾‹å„¿ç«¥å—œé ¸ç²’ç»†èƒžæ€§èƒƒè‚ é“ç–¾ç— ä¸´åºŠç‰¹å¾åˆ†æžï¼šä¸€é¡¹å¤šä¸­å¿ƒç ”ç©¶.

OBJECTIVES: To explore the clinical manifestations, endoscopic findings, histopathological changes, treatment, and prognosis of eosinophilic gastrointestinal disease (EGID) in children, with the aim of enhancing awareness among pediatricians about this condition. METHODS: Data of 267 children with EGID were prospectively collected from January 2019 to July 2022 at Jiangxi Children's Hospital, Hunan Children's Hospital, and Henan Children's Hospital. The age of onset, symptoms, physical signs, laboratory examination results, endoscopic findings, histopathological changes, and treatment outcomes were observed. RESULTS: Among the 267 children with EGID, the majority had mild (164 cases, 61.4%) or moderate (96 cases, 35.6%) clinical severity. The disease occurred at any age, with a higher prevalence observed in school-age children (178 cases). The main symptoms in infants were vomiting and hematemesis, while in toddlers, vomiting and bloody stools were prominent. Abdominal pain and vomiting were the primary symptoms in preschool and school-age children. Nearly half (49.4%) of the affected children showed elevated platelet counts on hematological examination, but there was no significant difference in platelet counts among children with mild, moderate, and severe EGID (P>0.05). Endoscopic findings in EGID children did not reveal significant specificity, and histopathological examination showed no specific structural damage. Among them, 85.0% (227 cases) received acid suppression therapy, 34.5% (92 cases) practiced dietary avoidance, 20.9% (56 cases) received anti-allergic medication, and a small proportion (24 cases, 9.0%) were treated with prednisone. Clinical symptoms were relieved in all patients after treatment, but three cases with peptic ulcers experienced recurrence after drug discontinuation. CONCLUSIONS: Mild and moderate EGID are more common in children, with no specific endoscopic findings. Dietary avoidance, acid suppression therapy, and anti-allergic medication are the main treatment methods. The prognosis of EGID is generally favorable in children.

Factors associated with medical students' self-regulated learning and its relationship with clinical performance: a cross-sectional study.

BACKGROUND: The importance of self-regulated learning (SRL) has been broadly recognised by medical education institutions and medical professionals. Self-regulated learning, which is a context-specific process, is affected by personal, contextual and social factors. Although many studies on exploring the factors that influenced SRL and the relationship of between SRL and clinical achievement levels have been carried out in western countries, little is known about the factors associated with self-regulated learning and its relationship with clinical performance among medical students in China. METHODS: A cross-sectional online survey was distributed to 3rd year clinical medicine students who were in the clinical clerkship stage in a medical college in Wuhan. We used Self-regulated Learning Scale for Undergraduates (SLSU) to measure the self-regulated learning of students and Objective Structured Clinical Examination (OSCE) in the national proficiency test to assess the clinical performance of students. The participation rate was 73.95% (193 students). An independent t-test and analysis of variance were used to analyse the factors associated with self-regulated learning. The relationship between self-regulated learning and clinical performance was analysed with multilinear regression analysis. RESULTS: Univariate analysis showed that having a clear career planning and a professional idol, providing full-time teaching clinical teachers in the clerkship department and seeking the help of the surrounding classmates and the guidance of teachers or senior students were significant predictors of self-regulated learning. Multilinear regression analysis has revealed a positive relationship among extrinsic goals (partial r = 0.171), clinical clerkship evaluation (partial r = 0.197) and clinical performance (F = 4.070, p = 0.004). CONCLUSIONS: Motivation-related personal and social factors related to clinical context could promote the SRL level of medical students in China. Extrinsic goals and clinical clerkship evaluation could facilitate students' clinical achievements on clinical skills. External support, such as clinical clerkship management, might improve clinical performance on clinical skills in clinical clerkship context.

[Etiology of ascites in 165 children]. / 165ä¾‹å„¿ç«¥è ¹æ°´çš„ç— å› åˆ†æž.

OBJECTIVES: To study the etiology and clinical features of children with ascites, so as to provide a basis for the diagnosis and treatment of ascites in children. METHODS: The medical data of the children with ascites, who were hospitalized from January 1, 2010 to December 31, 2019, were retrospectively reviewed. RESULTS: Among the 165 children with ascites, the male/female ratio was 1.53:1, and the mean age of onset was (6±4) years. The causes of ascites included surgical acute abdomen (39 children, 23.6%), infectious diseases (39 children, 23.6%), neoplastic diseases (27 children, 16.4%), hepatogenic diseases (18 children, 10.9%), pancreatitis (10 children, 6.1%), cardiogenic diseases (8 children, 4.8%), rheumatic immune diseases (6 children, 3.6%), and nephrogenic diseases (5 children, 3.0%). According to the age of onset, there were 33 infants, 24 young children, 30 preschool children, 41 school-aged children, and 37 adolescents. Surgical acute abdomen and hepatogenic diseases were the main causes of ascites in infants (P<0.05). Neoplastic disease was the leading cause in young children (P<0.05). Infectious diseases were the most common cause in adolescents (P<0.05). CONCLUSIONS: Surgical acute abdomen, infectious diseases, neoplastic diseases, and hepatogenic diseases are the common causes of ascites in children, and there are some differences in the leading cause of ascites between different age groups.

Solid-State Li-Ion Batteries Using Fast, Stable, Glassy Nanocomposite Electrolytes for Good Safety and Long Cycle-Life.

The development of safe, stable, and long-life Li-ion batteries is being intensively pursued to enable the electrification of transportation and intelligent grid applications. Here, we report a new solid-state Li-ion battery technology, using a solid nanocomposite electrolyte composed of porous silica matrices with in situ immobilizing Li(+)-conducting ionic liquid, anode material of MCMB, and cathode material of LiCoO2, LiNi1/3Co1/3Mn1/3O2, or LiFePO4. An injection printing method is used for the electrode/electrolyte preparation. Solid nanocomposite electrolytes exhibit superior performance to the conventional organic electrolytes with regard to safety and cycle-life. They also have a transparent glassy structure with high ionic conductivity and good mechanical strength. Solid-state full cells tested with the various cathodes exhibited high specific capacities, long cycling stability, and excellent high temperature performance. This solid-state battery technology will provide new avenues for the rational engineering of advanced Li-ion batteries and other electrochemical devices.

Fibroblast growth factor-21 concentration in serum and synovial fluid is associated with radiographic bone loss of knee osteoarthritis.

We aimed to evaluate whether FGF-21 concentration in serum and synovial fluid (SF) is associated with radiographic bone loss of knee osteoarthritis (OA). A total of 186 OA patients and 108 controls were recruited. The radiographic bone loss of knee OA was assessed by the Ahlbäck grading scale. FGF-21 concentration in serum and SF was measured by enzyme-linked immunosorbent assay (ELISA). We demonstrated that OA patients had significantly higher serum FGF-21 concentration compared with controls (204.30 [range 158.25-279.16] ng/L vs. 130.72 [range 94.93-218.03] ng/L, p < 0.01). FGF-21 concentration in serum was well correlated with that in paired SF samples (r = 0.668, p < 0.001). In OA patients, those with a higher Ahlbäck grade had significantly higher serum and SF FGF-21 concentration (p < 0.001 for both). FGF-21 concentration in serum and SF was significantly and independently associated with the Ahlbäck grade (r = 0.403, p < 0.001 and r = 0.410, p < 0.001; respectively). These findings indicated that FGF-21 might be a potential biomarker for predicting bone loss of OA. Therapeutic interventions by blocking FGF-21 signaling pathways to delay the degenerative process of OA warrants further investigations.

Preparation of malathion MIP-SPE and its application in environmental analysis.

Malathion is an organophosphorous insecticide for controlling insects on fruits and vegetables, miscellaneous household insects, and animal parasites. It is important to develop highly efficient and selective pre-treatment method for analyzing malathion residues in environment and samples from agricultural products based on the molecularly imprinted polymers (MIPs). In this study, we developed a tailor-made MIP method with highly specific recognization to the template. The MIPs were prepared using malathion as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker, azodiisobutyronitrile (AIBN) as an initiator, and the acetonitrile-chloroform (1:1, v/v) as a porogen. The molecular recognization mechanism of malathion and MAA was evaluated by molecular simulation, ultraviolet spectrometry (UV), and (1)H-nuclear magnetic resonance ((1)H-NMR). MAA interacted specifically with malathion by hydrogen bond with a ratio of 2:1. The MIPs exhibit a high affinity, recognition specificity, and efficient adsorption performance for malathion. The Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), surface area and porosimeter analyzer, thermogravimetric/differential thermal analyzer (TG/DTA) were used to characterize the properties of MIP. The malathion residues in soil, tap water, and cabbage were cleaned up by MIP-SPE, detected quantitatively using GC-FPD, and confirmed by GC-MS/MS. The limits of tap water, soil, and cabbage were confined to 0.001 mg L(-1), 0.004 and 0.004 mg kg(-1), respectively. The spiked recoveries of malathion were 96.06-111.49% (with RSD being 5.7-9.2%), 98.13-103.83% (RSD, 3.5-8.7%), and 84.94-93.69% (RSD, 4.7-5.8%) for tap water, soil, and cabbage samples, respectively. Thus, the method developed here can be used effectively in assessing malathion residues in multiple environmental samples. The aim of the study was to provide an efficient, selective, and accurate method for analyzing malathion at trace levels in multiple media.

An obesity-like gene MdTLP7 from apple (Malus × domestica) enhances abiotic stress tolerance.

Tubby-like proteins (TLPs) are found in a broad range of multicellular organisms. In mammals, genetic mutation of tubby or other TLPs can result in certain disease phenotypes related to animal specific characters: obesity, retinal degeneration, hearing loss, et al. Plants also harbor a large number of TLP genes, but the information in plants is far more limited. We identified a highly up-regulated obesity-like gene, MdTLP7, in our previous study of apple differential gene expression profile under chilling, indicating its possible role in plant abiotic stress tolerance. cDNA of MdTLP7 was amplified and expressed in Escherichia coli. In the solid and solution medium, the rate of growth and the quantity of the cell carrying MdTLP7 gene were significantly more than that of empty vector under salt and temperature stresses. To identify the functional region, serial deletion from both N-terminus and C-terminus of MdTLP7 was performed. In 415 amino acid polypeptide chain of MdTLP7, a middle conservative fragment (120-310 amino acid residues) played vital roles in stress tolerance. This fragment was involved in ß barrel of Tubby domain according to the model of Tubby domain. All above results suggested MdTLP7 confers stress-tolerance to E. coli cell against abiotic stresses.

Influencing factors of mental health of medical students in China.

This study investigated the mental health status of medical students in China, and analyzed the influencing factors in order to provide evidence for mental health education for medical students. A stratified cluster sampling method was used to recruit medical students from Huazhong University of Science and Technology, China. The questionnaire survey on general information and Symptom Checklist 90 (SCL-90) were used for investigation and analysis. The results showed among the 1137 valid questionnaires, 278 (24.45%) participants had SCL-90 score ≥ 160. The top three mental problems of medical students were obsessive-compulsive disorder, interpersonal sensitivity and depression in terms of the factor score ≥ 2.5 and the number of participants who reflected on the diseases. The third-year medical students had the worst mental health status, and fifth-year medical students had the best mental health status. Students from rural area had more psychological problems than those from urban area; furthermore, students with high professional satisfaction, those who were the single child of the family, non-poor students, and those whose parents had high education level had better mental health status. It was concluded that the mental health of medical students is not optimistic in China. Medical students have some mental health problems of different degrees. Factors that influence the mental health of medical students include academic pressure, professional satisfaction level and family environment.

Factors influencing the utilization of postpartum visits among rural women in China.

Postpartum visits (PPVs) are still underutilized in rural China, and identification of factors that influence PPV use is important in ensuring the utilization of maternal health services and for wellbeing of women. A cross-section study was undertaken to collect related data from 347 rural women interviewed six weeks or more after delivery, and an ANOVA was performed to find whether there were significant differences in the number of PPVs among different rural areas in China. According to Andersen's socio-behavioral model of health service use, factors were divided into equitable and inequitable ones. Chi-squared test, univariate and multiple analyses were used to determine the equity of PPV use by identifying factors that were most strongly associated with the use of a PPV. The results showed that 20.2% of the respondents (n=70) did not receive any PPVs, and 62.5% (n=173) of those who had PPVs (n=277) did not receive standard PPVs (referring to at least 3 visits). There was no significant difference among different rural areas in terms of the number of PPVs (F=1.514, P=0.211). Multiple regression analyses revealed that enabling factors such as compensation for delivery expense [OR (95% CI)=2.825 (1.331, 5.995)], village type [OR (95% CI)=1.802 (1.021, 3.182)] and service quality [OR (95% CI)=1.847 (1.074, 3.176)] were strongly associated with PPV use. Both enabling factors such as home visits [OR (95% CI)=1.855 (1.085, 3.174)], service quality [OR (95% CI)=1.993 (1.155, 3.439)] and need factors such as low birth weight [OR (95% CI)=4.424 (1.482, 13.203)] were significantly associated with standard PPV use. Our results suggested that the equitable access to PPVs has been considerably improved in rural areas in China. The associations between inequitable factors and PPV use warrant further exploration, and policies aimed at improving quality and patterns of service supply are needed in order to ensure a full equitable access to maternal health services.

A method developed for determination of heptachlor and its metabolites from pork.

A new method has been developed to determine heptachlor and its metabolites heptachlor-exo-epoxide and heptachlor-endo-epoxide in pork. The pork samples were extracted with acetone-n-hexane (2:8, V:V) and cleaned up by gel permeation chromatography and florisil solid-phase extraction cartridge. The extract was then determined by gas chromatography equipped with electron capture detector (GC-ECD), followed by validation using gas chromatography-mass spectrometry (GC-MS) with negative chemical ionization. Linearity of calibration curves ranged from 0.01 to 0.5 mg L(-1), with correlation coefficients of more than 0.9980 for GC-ECD and GC-MS, respectively. At spiked concentrations of 0.01, 0.05, and 0.1 mg kg(-1), the average recovery and relative standard deviation values were 87.1-102.2 and 4.0-11.3%, respectively. The limit of quantification for each analyte was 0.01 mg kg(-1), which satisfied the current maximum residue limit permitted in pork. Our results showed that the method developed was successfully used to determine heptachlor and heptachlor epoxide residues in real pork samples.

Tuning the End Alkyl Chain of the Ether Solvent to Stabilize the Electrode/Electrolyte Interfaces in the NCM-Li Battery.

Lithium metal batteries (LMBs) combined with a high-voltage nickel-rich cathode show great potential in meeting the growing need for high energy density. The lack of advanced electrolytes has been a major obstacle in the commercialization of high-voltage lithium metal batteries (LMBs), as these electrolytes need to effectively support both a stable lithium metal anode (LMA) and a high-voltage cathode (>4 V vs Li+/Li). In this work, by extending the two terminal methyl groups in DIGDME and TEGDME to n-butyl groups, we design a new weakly solvating electrolyte (2 M LIFSI+TEGDBE) that enables the stable cycling of NMC83 (LiNi0.83Co0.12Mn0.05O2) cathodes. The NMC83 cell exhibits a high and stable Coulombic efficiency (CE) of over 99%, as well as capacity retention of approximately 99.8% after 100 cycles at 0.3 C. X-ray photoelectron spectroscopy analysis (XPS) and high-resolution transmission electron microscope (HRTEM) images revealed that the anion species decomposed first, resulting in the formation of a cathode-electrolyte interface (CEI) film predominantly consisting of decomposition products from the anions on the positive electrode surface. This work links the functional group of solvents with the solvation structure and electrochemical performance of ether-based electrolytes, providing a distinctive sight to design advanced electrolytes for high-energy-density LMBs.

Highly selective recovery of gold and silver from E-waste via stepwise electrodeposition directly from the pregnant leaching solution enabled by the MoS2 cathode.

The recycling of electronic waste, i.e., waste Printed Circuit Boards (WPCBs), provides substantial environmental and economic advantages. In fact, the concentration of valuable precious and base metals in WPCBs is even higher compared to those found in mined ores. Nevertheless, it is still challenging to selectively extract precious metals with low concentrations from the pregnant leaching solution, due to the co-deposition of base metals, like Cu, which have higher concentrations. In this research, stepwise recovery of precious metals and copper directly from WPCBs thiosulfate leaching solution was facilitated by the Ti cathode coated with MoS2 (MoS2/Ti). The in-situ enrichment of Au(S2O3)23- and Ag(S2O3)23- at the surface of MoS2 enables the high efficiency and selectivity of electrodeposition, which has been confirmed through COMSOL Multiphysics simulations and visualization. As a result, the first-step electrodeposition at 0.6 V recovered 92.44 % Au and 98.18 % Ag without any co-deposition of Cu. Subsequently, the second-step recovery employed a constant current of 0.03 A, achieving 100 % recovery of copper within 12 h. Furthermore, this study optimized the reduction potential, NH3·H2O concentration, and S2O32- concentration for the stepwise electrodeposition process. These findings provide valuable insights for establishing a closed loop circular economy in the electronics industry.

[Determination of 12 prohibited veterinary drug residues in pig urine by ultra high performance liquid chromatography-tandem mass spectrometry].

A method was established for the simultaneous detection of 12 prohibited veterinary drugs, including ß2-receptor agonists, nitrofuran metabolites, nitroimidazoles, chlorpromazine, and chloramphenicol, in pig urine. The sample was pretreated by enzymolysis, acid hydrolysis/derivatization, and liquid-liquid extraction combined with solid-phase extraction. Detection was performed using ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Ammonium acetate solution (0.2 mol/L, 4.5 mL) and ß-glucuronidase/aryl sulfatase (40 µL) were added to the sample, which was subsequently enzymolized at 37 ℃ for 2 h. Then, 1.5 mL of 1.0 mol/L hydrochloric acid solution and 100 µL of 0.1 mol/L o-nitrobenzaldehyde solution were added to the sample. The mixture was incubated at 37 ℃ for 16 h, and the analytes were extracted with 8 mL of ethyl acetate by liquid-liquid extraction. The lower aqueous phase obtained after extraction was extracted and purified using a mixed cation-exchange solid-phase extraction column. The extracts were combined, the extraction solution was blow-dried with nitrogen, and the residue was redissolved for determination. The samples were analyzed under multiple-reaction monitoring mode with both positive and negative electrospray ionization, and quantified using an isotope internal standard method. The correlation coefficients (r) of the 12 compounds were >0.99. The limits of detection (LODs) and quantification (LOQs) of chloramphenicol were 0.05 and 0.1 µg/L, respectively, and the LODs and LOQs of the other compounds were 0.25 and 0.5 µg/L, respectively. The mean recoveries and RSDs at 1, 2, and 10 times the LOQ were 83.6%-115.3% and 2.20%-12.34%, respectively. The proposed method has the advantages of high sensitivity, good stability, and accurate quantification; thus, it is suitable for the simultaneous determination of the 12 prohibited veterinary drug residues in pig urine.

Serum fetuin-A levels are inversely associated with clinical severity in patients with primary knee osteoarthritis.

The present study aimed to detect serum fetuin-A levels in knee osteoarthritis (OA) patients and to investigate their correlation with clinical severity. We enrolled 215 knee OA patients and 76 healthy controls. We measured serum fetuin-A levels by enzyme-linked immunosorbent assay and assessed the correlation between serum fetuin-A levels and Kellgren-Lawrence grades as well as Western Ontario and McMaster Universities Arthritis Index scores in OA patients. Our results demonstrated that serum fetuin-A levels were independently and negatively correlated with greater clinical severity in OA patients.

Difference in subchondral cancellous bone between postmenopausal women with hip osteoarthritis and osteoporotic fracture: implication for fatigue microdamage, bone microarchitecture, and biomechanical properties.

OBJECTIVE: Osteoarthritis (OA) and osteoporosis (OP) of the hip rarely occur in the same patient. The purpose of this study was to determine whether this difference might be attributable to the different quantity and quality of subchondral cancellous bone in the two conditions. METHODS: Subchondral cancellous bone from the femoral head was obtained at the time of hip arthroplasty from 60 postmenopausal women, 30 with OA and 30 with OP. In each group, 10 specimens were subjected to compressive fatigue loading and 20 were left nonloaded. Specimens were examined by compressive mechanical testing, micro-computed tomography scanning, fluorescence microscopy, and nanoindentation techniques. RESULTS: Both the ultimate stress and the elastic modulus of cancellous bone from OA patients were significantly higher than those of cancellous bone from OP patients (P < 0.05). Compared to cancellous bone from OP patients, the bone volume fraction and trabecular thickness were significantly increased, but bone matrix mineralization was significantly decreased, in cancellous bone from OA patients (P < 0.05 for each comparison). The microcrack density was significantly higher in OP cancellous bone than in OA cancellous bone (P < 0.001), irrespective of fatigue loading. In addition, fatigue loading resulted in a significant increase in microcrack density in both OA and OP cancellous bone (P < 0.001). There was no significant difference in nanoindentation elastic modulus and hardness between cancellous bone from OA and OP patients, as well as between bones with and without fatigue loading. CONCLUSION: The difference in mechanical properties between OA and OP cancellous bone is attributed to different bone mass and bone structure. OP cancellous bone is susceptible to fatigue damage due to insufficient structure. However, increased bone volume and plate-like structure provide OA cancellous bone a superior capacity to resist fatigue damage.

Impact evaluation of HIV/AIDS education in rural Henan province of China.

Nowadays, there is a trend of HIV prevalence transmitting from high-risk group to average-risk group in China. Rural China is the weak link of HIV prevention, and rural areas of Henan province which is one of the most high-risk regions in China have more than 60% of the AIDS patients in the province. Thus, improving the HIV awareness and implementing health education become the top-priority of HIV/AIDS control and prevention. A multistage sampling was designed to draw 1129 people living with HIV/AIDS (PLWHAs) and 1168 non-PLWHAs in 4 prevalence counties of Henan province. A health promoting and social-psychological support model was constructed to improve the health knowledge of participants. Chi-square tests and unconditional logistic regression were performed to determine the intervention effect and influencing factors. All groups had misunderstandings towards the basic medical knowledge and the AIDS transmission mode. Before the intervention, 59.3% of the HIV/AIDS patients and 74.6% of the healthy people had negative attitudes towards the disease. There was statistically significant difference in the improvement of knowledge, attitude and action with regards to HIV prevention before and after intervention (P<0.05). PLWHAs who were males (OR=1.731) and had higher education level (OR=1.910) were found to have better HIV/AIDS health knowledge, whereas older PLWHAs (OR=0.961) were less likely to have better HIV/AIDS health knowledge. However, the intervention effect was associated with the expertise of doctors and supervisors, the content and methods of education, and participants' education level. It was concluded that health education of HIV/AIDS which positively influences the awareness and attitude of HIV prevention is popular in rural areas, therefore, a systematic and long-term program of HIV control and prevention is urgently needed in rural areas.

One-Step Solid-State Synthesis of Ni-Rich Cathode Materials for Lithium-Ion Batteries.

Ni-rich cathodes are expected to serve as critical materials for high-energy lithium-ion batteries. Increasing the Ni content can effectively improve the energy density but usually leads to more complex synthesis conditions, thus limiting its development. In this work, a simple one-step solid-state process for synthesizing Ni-rich ternary cathode materials NCA (LiNi0.9Co0.05Al0.05O2) was presented, and the synthesis conditions were systematically studied. It was found that the synthesis conditions have a substantial impact on electrochemical performance. Furthermore, the cathode materials produced through a one-step solid-state process exhibited excellent cycling stability, maintaining 97.2% of their capacity after 100 cycles at a rate of 1 C. The results show that a one-step solid-state method can successfully synthesize Ni-rich ternary cathode material, which has great potential for application. Optimizing the synthesis conditions also provides valuable ideas for the commercial synthesis of Ni-rich cathode materials.

A Critical Review on the Recycling Strategy of Lithium Iron Phosphate from Electric Vehicles.

Electric vehicles (EVs) are one of the most promising decarbonization solutions to develop a carbon-negative economy. The increasing global storage of EVs brings out a large number of power batteries requiring recycling. Lithium iron phosphate (LFP) is one of the first commercialized cathodes used in early EVs, and now gravimetric energy density improvement makes LFP with low cost and robustness popular again in the market. Developments in LFP recycling techniques are in demand to manage a large portion of the EV batteries retired both today and around ten years later. In this review, first the operation and degradation mechanisms of LFP are revisited aiming to identify entry points for LFP recycling. Then, the current LFP recycling methods, from the pretreatment of the retired batteries to the regeneration and recovery of the LFP cathode are summarized. The emerging direct recovery technology is highlighted, through which both raw material and the production cost of LFP can be recovered. In addition, the current issues limiting the development of the LIBs recycling industry are presented and some ideas for future research are proposed. This review provides the theoretical basis and insightful perspectives on developing new recycling strategies by outlining the whole-life process of LFP.

Regulating Surface Oxygen Activity by Perovskite-Coating-Stabilized Ultrahigh-Nickel Layered Oxide Cathodes.

Ultrahigh-Ni layered oxides are proposed as promising cathodes to fulfill the range demand of electric vehicles; yet, they are still haunted by compromised cyclability and thermal robustness. State-of-the-art surface coating has been applied to solve the instability via blocking the physical contact between the electrolyte and the highly active Ni4+ ions on the cathode surface, but it falls short in handling the chemo-physical mobility of the oxidized lattice oxygen ions in the cathode. Herein, a direct regulation strategy is proposed to accommodate the highly active anionic redox within the solid phase. By leveraging the stable oxygen vacancies/interstitials in a lithium and oxygen dual-ion conductor (layered perovskite La4 NiLiO8 ) coating layer, the reactivity of the surface lattice oxygen ion is dramatically restrained. As a result, the oxygen release from the lattice is suppressed, as well as the undesired irreversible phase transition and intergranular mechanical cracking. Meanwhile, the introduced dual-ion conductor can also facilitate lithium-ion diffusion kinetics and electronic conductivity on the particle surface. This work demonstrates that accommodating the anionic redox chemistry by dual-ion conductors is an effective strategy for capacity versus stability juggling of the high-energy cathodes.