Pd Single-Atom Loaded Ce-Zr Solid Solution Catalysts Prepared by Flame Spray Pyrolysis for Efficient CO Catalytic Oxidation.

Single-atom catalysts (SACs) exhibit remarkable catalytic activity at each metal site. However, conventionally synthesized single-atom catalysts often possess low metal loading, thereby constraining their overall catalytic performance. Here, a flame spray pyrolysis (FSP) method for the synthesis of a single-atom catalyst with a high loading capacity of up to 1.4 wt.% in practice is reported. CeZrO2 acts as a carrier and provides a large number of anchoring sites, which promotes the high-density generation of Pd, and the strong interaction between the metal and the support avoids atom aggregation. Pd-CeZrO2 series catalysts have excellent CO oxidation performance. When 0.97 wt.% Pd is added, the catalytic activity is the highest, and the temperature can be reduced to 120 °C. This work presented here demonstrates that FSP, as an inherently scalable technique, allows for elevating the single-atom loading to achieve an increase in its catalytic performance. The method presented here more options for the preparation of SACs.

Revealing the Effect of Electronic Configuration in Cux Species on CO2 Photoreduction Characteristic Products.

As of the present time, the in-depth study of the structure-activity relationship between electronic configuration and CO2 photoreduction performance is often overlooked. Herein, a series of Cux species modified CeO2 nanodots are constructed in situ by flame spray pyrolysis (FSP) to achieve an efficient photocatalytic CO2-to-C2 conversion with an electron utilization of up to 142.5 µmol g-1. Through an in-depth study of the electronic behavior and catalytic pathways, it is found that the Cu0/Cu+ species in the coexistence state of Cu0/Cu+/Cu2+ can optimize the energy band structure, photocurrent stability, and provide a kinetic basis for the active surface catalytic reaction process that requires the conversion of multiple electrons into C2 products, which ultimately enhances the CO2-to-C2H6 photoreduction by 3.8-fold and that for CO2-to-C2H4 photoreduction by 5.2-fold. Besides, the Cu2+ species in the coexistence state of Cu0/Cu+/Cu2+ are able to regulate the electronic behavior and the choice of the catalytic pathway, enabling the transitions between CO2-to-C2H6 and CO2-to-C2H4. This work indicates that electronic configuration optimization is an effective strategy to significantly enhance the CO2 photoreduction performance and provides new ideas for the design and synthesis of high-performance heterostructure photocatalysts.

Rich-Carbonyl Carbon Catalysis Facilitating the Li2CO3 Decomposition for Cathode Lithium Compensation Agent.

The active lithium loss of lithium-ion batteries can be well addressed by adding a cathode lithium compensation agent. Due to the poor conductivity and electrochemical activity, lithium carbonate (Li2CO3) is not considered as a candidate. Herein, an effective cathode lithium compensation agent, the recrystallized Li2CO3 combined with large specific surface area disordered porous carbon (R-LCO@SPC) is prepared. The screened SPC makes it easier for nano-sized Li2CO3 to adsorb and decompose on carbon substrate, meantime, exposing plenty of catalytic active sites of C═O, which can significantly improve the electrochemical activity and conductivity of Li2CO3, thus greatly reducing the decomposition potential of Li2CO3 (4.0 V) and releasing high irreversible capacity (580 mAh g-1) compared to the unmodified Li2CO3 (nearly no capacity above 4.6 V). Meantime, the Li2CO3 can disappear completely without any by-product after the initial cycle accompanied by partially dissolved in electrolyte, optimizing the composition of SEI. The resultant lithium compensation agent applied to LMFP//graphite full cell exhibits a 19.1% increase in energy density, enhancing the rate and cycling performance, demonstrating great practical applications potential in high energy density lithium-ion batteries.

Simultaneous Detection of Citric Acid and Oxalic Acid Based on Dual Spectrum and Biomimetic Peroxidase for Urolithiasis Screening with a Fully Automatic Urine Analyzer.

Urolithiasis stands as a prevalent ailment within the urinary system, with hyperoxaluria and hypocitraturia being the most frequent manifestations characterized by excessive oxalic acid (OA) and deficient citric acid (CA) levels in urine. Detecting these compounds in urine quantitatively holds paramount importance for early urolithiasis screening. Existing methodologies fall short in achieving simultaneous and on-site identification of OA and CA, posing challenges for accurate urolithiasis screening. Addressing this concern, the study successfully accomplishes the concurrent identification of OA and CA in urine through a combination of dual-spectral analysis and biomimetic peroxidase utilization. Bovine serum albumin and dithiothreitol-modified copper nanoclusters (BSA-DTT-CuNCs) are employed as biomimetic peroxidases, effectively mitigating interference and enabling the simultaneous determination of OA and CA. The quantification range spans from 0 to 12 mm for OA and 0.5 to 2.5 mm for CA, with detection limits of 0.18 and 0.11 mm, respectively. To facilitate swift and on-location urine analysis, a fully automated urine analyzer (FAUA) is introduced that streamlines the process of biomarker pretreatment and identification within urine samples. Validation with real urine samples from urolithiasis patients demonstrates the method's diagnostic precision, highlighting the dual-spectral technique and analyzer's promising role in urolithiasis screening.

The Micron-Droplet-Confined Continuous-Flow Synthesis of Freestanding High-Entropy-Alloy Nanoparticles by Flame Spray Pyrolysis.

Alloying multiple immiscible elements into a nanoparticle with single-phase solid solution structure (high-entropy-alloy nanoparticles, HEA-NPs) merits great potential. To date, various kinds of synthesis techniques of HEA-NPs are developed; however, a continuous-flow synthesis of freestanding HEA-NPs remains a challenge. Here a micron-droplet-confined strategy by flame spray pyrolysis (FSP) to achieve the continuous-flow synthesis of freestanding HEA-NPs, is proposed. The continuous precursor solution undergoes gas shearing and micro-explosion to form nano droplets which act as the micron-droplet-confined reactors. The ultrafast evolution (<5 ms) from droplets to <10 nm nanoparticles of binary to septenary alloys is achieved through thermodynamic and kinetic control (high temperature and ultrafast colling). Among them, the AuPtPdRuIr HEA-NPs exhibit excellent electrocatalytic performance for alkaline hydrogen evolution reaction with 23 mV overpotential to achieve 10 mA cm-2, which is twofold better than that of the commercial Pt/C. It is anticipated that the continuous-flow synthesis by FSP can introduce a new way for the continuous synthesis of freestanding HEA-NP with a high productivity rate.

Confined Synthesis of Noble Metal Clusters Assisted by Liquid Film for Photocatalytic CO2 Reduction.

The important concept of confined synthesis is considered a promising strategy for the design and synthesis of definable nanostructured materials with controllable compositions and specific morphology, such as highly loaded single-atom catalysts capable of providing abundant active sites for photocatalytic reactions. In recent years, researchers have been working on developing new confined reaction systems and searching for new confined spaces. Here, we present for the first time the concept of a bubble liquid film as a novel confined space. The liquid film has a typical sandwich structure consisting of a water layer, sandwiched between the upper and lower surfactant layers, with the thickness of the intermediate water layer at the micro- and nanometer scales, which can serve as a good confinement. Based on the above understanding and combined with the photodeposition method, we successfully confined synthesized Ag/TiO2, Au/TiO2, and Pd/TiO2 photocatalysts in liquid film. By HAADF-STEM, it can be seen that the noble metal morphologies are all nanoclusters of about 1 nm and are highly uniformly dispersed on the TiO2 surface. Compared with photodeposition in solution, we believe that the surfactant molecular layer restricts a limited amount of precursor to the liquid film, avoiding the accumulation of noble metals and the formation of large particle size nanoparticles. The liquid film, meanwhile, restricts the migration path of noble metal precursors, allowing for thorough in situ photodeposition and enables the complete and uniform dispersion of noble metal precursors, greatly reducing the photodeposition time. The uniform loading of the three noble metals proved the universality of the method, and the catalysts showed high activity for photocatalytic CO2 reduction. The rates of reduction of CO2 to CO over the Ag/TiO2 photocatalytic reached 230 µmol g-1 h-1.This study provides a new idea for the expansion of the confined reaction system and a reference for the study of liquid film as the confined space.

Prediction of prognostic and immune therapy response in lung adenocarcinoma based on MHC-I-related genes.

OBJECTIVES: The study investigated the prognostic and immune predictive potential of major histocompatibility complex class I (MHC-I) in lung adenocarcinoma (LUAD). MATERIALS AND METHODS: With The Cancer Genome Atlas (TCGA)-LUAD and Gene Expression Omnibus datasets (GSE26939, GSE72094) as the training and validation sets, respectively, we used Cox regression analysis to construct a prognostic model, and verified independence of riskscore. The predictive capacity of the model was assessed in both sets using the receiver operating characteristic curve and Kaplan-Meier survival curves. Immune analysis was performed by using ssGSEA. Additionally, immune checkpoint blockade therapy was assessed by using immunophenoscore, Tumor Immune Dysfunction and Exclusion score. Based on the cMAP database, effective small molecule compounds were predicted. RESULTS: A prognostic model was established based on 8 MHC-I-related genes, and the predictive capacity of the model was accurate. Immune analysis results revealed that patients classified as high-risk had lower levels of immune cell infiltration and impaired immune function. The low-risk group possessed a better response to immune checkpoint blockade therapy. Theobromine and pravastatin were identified as having great potential in improving the prognosis of LUAD. CONCLUSION: Overall, the study revealed MHC-I-related molecular prognostic biomarkers as robust indicators for LUAD prognosis and immune therapy response.

Highly reusable Bi2O3/electron-Cu-shuttle in-situ immobilized polyacrylonitrile fibrous mat for efficient photocatalytic degradation of methylene blue and rhodamine B dyes.

Organic semiconductor-based photocatalysts have been alluring due to their edge over inorganic photocatalysts. In this study, a reusable copper-bismuth oxide/polyacrylonitrile (Cu-Bi2O3/PAN) fibrous mat was prepared by fast-process flame spray pyrolysis and electrospinning for photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) dyes. The results confirmed a well-defined morphology of Cu-Bi2O3/PAN fibers and good coordination of flame-made Cu-Bi2O3 particles with the functional groups of PAN. The Cu-Bi2O3/PAN fibrous mat exhibits remarkable photocatalytic performance of 96.2% MB and 98.6% RhB degradation, with a reaction rate as high as about 4.5- and 10.2-times than that of flame-made Cu-Bi2O3 particles and PAN under neutral condition, even after 10 cycles. The Cu-Bi2O3/PAN exhibits complete degradation of MB and RhB in 90 and 150 min under alkaline and slightly acidic conditions, respectively. The synergistic effect of Cu-Bi2O3 and coordination bond between particles and functional groups of PAN promoted carrier migration, suppressed recombination of carriers and provided abundant radicals on the surface of the mat. Superoxide and hydroxyl radicals were the major active species involved in the degradation of RhB and MB, respectively. This work provides an insight into designing the Cu-metal-shuttle based photocatalysts to optimize fibrous mat application in water remediation.

Long-lifespan Zinc-ion Capacitors Enabled by Anodes Integrated with Interconnected Mesoporous Chitosan Membranes through Electrophoresis-driven Phase Separation.

The advancement of highly secure and inexpensive aqueous zinc ion energy storage devices is impeded by issues, including dendrite growth, hydrogen evolution and corrosion of zinc anodes. It is essential to modify the interface of zinc anodes that homogenizes ion flux and facilitates highly reversible zinc planarized deposition and stripping. Herein, by coupling zinc ion coordination with acid-base neutralization under the driving of electrophoresis, manageable mesoscopic phase separation for constructing chitosan frameworks was achieved, thereby fabricating interconnected mesoporous chitosan membranes based heterogeneous quasi-solid-state electrolytes integrated with anodes. The framework is constructed by twisted chitosan nanofiber bundles, forming a three-dimensional continuous spindle-shaped pore structure. With this framework, the electrolyte provides exceptional ion conductivity of 25.1 mS cm-1 , with a puncture resistance strength of 2.3 GPa. In addition, the amino groups of chitosan molecule can make the surface of the framework positively charged. Thus, reversible zinc planarized deposition is successfully induced by the synergistic effect of stress constraint and electrostatic modulation. As a result, as-assembled zinc ion capacitor has an excellent cycle life and sustains the capacity by over 95 % after 20000 cycles at a current density of 5 A g-1 . This research presents a constructive strategy for stable electrolytes-integrated zinc anodes.

Strong interlayer coupling in p-Te/n-CdSe van der Waals heterojunction for self-powered photodetectors with fast speed and high responsivity.

Self-driven photodetectors, which can detect optical signals without external voltage bias, are highly attractive in the field of low-power wearable electronics and internet of things. However, currently reported self-driven photodetectors based on van der Waals heterojunctions (vdWHs) are generally limited by low responsivity due to poor light absorption and insufficient photogain. Here, we report p-Te/n-CdSe vdWHs utilizing non-layered CdSe nanobelts as efficient light absorption layer and high mobility Te as ultrafast hole transporting layer. Benefiting from strong interlayer coupling, the Te/CdSe vdWHs exhibit stable and excellent self-powered characteristics, including ultrahigh responsivity of 0.94 A W-1, remarkable detectivity of 8.36 × 1012 Jones at optical power density of 1.18 mW cm-2 under illumination of 405 nm laser, fast response speed of 24 µs, large light on/off ratio exceeding 105, as well as broadband photoresponse (405-1064 nm), which surpass most of the reported vdWHs photodetectors. In addition, the devices display superior photovoltaic characteristics under 532 nm illumination, such as large Voc of 0.55 V, and ultrahigh Isc of 2.73 µA. These results demonstrate the construction of 2D/non-layered semiconductor vdWHs with strong interlayer coupling is a promising strategy for high-performance and low-power consumption devices.

Close-Contact Oxygen Vacancies Synthesized by FSP Promote the Supplement of Active Oxygen Species To Improve the Catalytic Combustion Performance of Toluene.

Catalytic combustion is an important means to reduce toluene pollution, and improving the performance of catalytic combustion catalysts is of great significance for practical applications. The study of oxygen vacancies is one of the key steps to improve catalyst performance. Here, two different oxygen vacancy structures were well-defined and controllably synthesized by flame spray pyrolysis (FSP) to evaluate their effect on the catalytic combustion performance of toluene. The closely contacted oxygen vacancies (c-Vo) enhance the oxygen activation capacity of the catalyst, and the temperature of the first oxygen desorption peak and hydrogen reduction peak is 56 and 37 °C lower than the separated oxygen vacancy (s-Vo) sample, respectively. The oxygen activation energy barrier on the c-Vo is calculated to be negligible of only 0.04 eV. Both in situ DRIFT and DFT calculations indicate that the c-Vo structure accelerates the catalytic oxidation of p-toluene molecules. Moreover, due to the unique characteristics of high-temperature synthesis and rapid quenching, FSP brings excellent water resistance and high-temperature stability to the catalyst. In conclusion, utilizing the FSP in situ reduction strategy can create more c-Vo to improve the catalytic combustion performance of toluene.

Association between the weight-adjusted waist index and stroke: a cross-sectional study.

BACKGROUND: The weight-adjusted waist index (WWI) is a new measure of obesity, and this study aimed to determine the association between the WWI and stroke. METHODS: Using the National Health and Nutrition Examination Survey (NHANES) 2011-2020 dataset, cross-sectional data from 23,389 participants were analysed. The correlation between the WWI and stroke was investigated through multivariate logistic regression and smoothing curve fitting. Subgroup analysis and interaction tests were also carried out. RESULTS: The research involved 23,389 participants, of whom 893 (3.82%) had a stroke. The fully adjusted model revealed a positive correlation between the WWI and stroke [1.25 (1.05, 1.48)]. Individuals who were in the highest quartile of WWI exhibited a 62% higher likelihood of experiencing a stroke than those in the lowest quartile [1.62 (1.06, 2.48)]. Subgroup analysis and interaction tests revealed that this positive correlation was similar in different population settings (all P for interaction > 0.05). CONCLUSION: A higher WWI was associated with a higher prevalence of stroke. The results of this study underscore the value of the WWI in stroke prevention and management.

[Using Liver Function Indicators to Predict Massive Blood Transfusion in Orthotopic Liver Transplantation].

Objective: To explore the predictive effect of preoperative liver function indicators for intraoperative massive blood transfusion in orthotopic liver transplantation and to establish a prediction model. Methods: We retrospectively analyzed the relevant data of 607 patients who underwent orthotopic liver transplantation in the Department of Liver Surgery, West China Hospital, Sichuan University between January 1, 2015 and June 30, 2021. According to the intraoperative transfusion volume of leukocyte-reduced red blood cells in additive solution, the patients were divided into a massive blood transfusion (MBT) group and a non-massive blood transfusion (NMBT) group. Univariate and multivariate logistic regressions were performed to analyze the risk factors of intraoperative MBT in orthotopic liver transplantation, the calibration of the predictive model was assessed by Hosmer-Lemeshow test, and the discrimination power of the predictive model was measured by area under the curve ( AUC) of the receiver operating characteristic (ROC) curve. Results: According to the results of logistic regression, alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB), and Child-Pugh score showed no correlation with the risk of MBT in orthotopic liver transplantation operation. Platelet count (PLT) (odds ratio [ OR]=0.90, 95% confidence interval [ CI]: 0.09-0.19, P=0.02), international normalized ratio (INR) ( OR=19.43, 95% CI: 7.64-19.44, P<0.01), prothrombin time (PT) ( OR=1.43, 95% CI: 1.25-1.63, P<0.01), and activated partial thromboplastin time (APTT) ( OR=0.92, 95% CI: 0.90-0.95, P<0.01) were identified as the risk factors of intraoperative MBT in orthotopic liver transplantation. The Hosmer-Lemeshow test showed that the predictive model had good calibration ( χ 2=9.06, P=0.48) and discrimination power ( AUC=0.80, 95% CI 0.766-0.834, P<0.01). Conclusion: A predictive model based on the preoperative PLT, INR, PT, and APTT of patients undergoing orthotopic liver transplantation was established and can be used to predict the risk of intraoperative MBT in liver transplantation patients.

[An Integrated Audio-Visual-Olfactory Virtual Reality False Feeding Device: Research, Development, and Design].

Objective: To resolve the problem of the lack of sensory stimulation from the colors and aromas of food when patients are given enteral nutrition support by tube feeding or simple oral administration, an immersive virtual reality (VR) sham feeding device integrating audio, visual, and olfactory sense perceptions was developed independently and the usability of the device was tested. Methods: Relying on the multidisciplinary cooperation of nursing, mechanical engineering, and computer science and using as a reference the characteristics of gastric tube and oxygen tube placement in clinical patients, we carried out 3D modeling and printing of the exterior framework of the odor box. Unity 3d.5.x, a mainstream virtual engine tool, was used to create scenarios. The device could create visual stimulation through 3 VR dining scenarios, 23 kinds of food, and comfortable dining environment. The sound of chewing was played to simulate the dining process and provide auditory stimulation. Through the independently researched and developed olfactory odor box, corresponding food aromas were sprayed out for olfactory stimulation. After the equipment prototype was created, 10 patients were recruited to perform users' subjective evaluation of the usability of the equipment. Results: A VR sham feeding device integrating audio-visual-olfactory stimulation was successfully developed. In the visual effect evaluation, all users commented that the vision was clear and unimpeded, and that the menu program could follow their rotation movement. Eight people considered the scenes to be rather realistic. In the auditory effect evaluation, all users stated that the volume of the sound was appropriate, and that they would hear a chewing sound being played when the food was approaching. In the olfactory effect evaluation, 9 people stated that they smelled the food aromas when the food was approaching, and that they thought the odor was real or partially real. On the whole, the equipment was convenient to use and all users thought that the equipment had clear presentation and could run stably and smoothly. No adverse reactions, such as dizziness, occurred in any users. Conclusion: Successfully presenting visual, auditory, and olfactory stimuli, the prototype device passed the subjective usability test. The prototype device effectively expands the application prospects of VR in the medical field. In the future, it will be applied to patient populations, including surgical patients, patients with eating disorders, obesity, and loss of appetite, and other patients who cannot take in food through their mouths. The prototype device provides new ideas for promoting enhanced recovery after surgery and improving patient experience.

[First-Class Nursing Discipline Construction Spearheads the Cultivation of First-Class Talents].

Cultivating first-class talents is a key task of the Double First-Class Initiative, a national plan to build a number of world-class universities and disciplines in China by the end of 2050. On the basis of reviewing the history of the development of the nursing discipline, we analyzed, herein, opportunities and challenges of nursing professional training under the strategic guidance of the Double First-Class Initiative. We proposed suggestions on the cultivation of first-class nursing professionals of the future by considering the following aspects, constructing a theoretical system of ideological and political education for nursing education with Chinese characteristics, exploring for ways to develop a nursing knowledge system and personnel training model around the axis of a life-course approach to health, building "nursing plus" interdisciplinary clusters to cultivate innovative talents with interdisciplinary integrated abilities, enhancing efforts to recruit and cultivate scientific and technological talents, optimizing in an all-round way the composition of qualified nursing personnel, gaining the support of first-class research platforms, and creating incubation centers for innovative and outstanding nursing professionals.

Biomimetic Assembly of Spore@ZIF-8 Microspheres for Vaccination.

Vaccines have been one of the most powerful weapons to defend against infectious diseases for a long time now. Subunit vaccines are of increasing importance because of their safety and effectiveness. In this work, a Bacillus amyloliquefaciens spore@zeolitic imidazolate framework-8 (ZIF-8) vaccine platform is constructed. The ovalbumin (OVA) is encapsulated in the ZIF-8 shells as a model antigen to form a spore@OVA@ZIF-8 (SOZ) composite. The assembly of ZIF-8 improves the loading content of OVA on the spores and provides OVA with long-term protection. The SOZ composite enhances the immunization efficacy in multiple ways, such as facilitation of antigen uptake and lysosome escape, stimulation of dendritic cells to mature and secrete cytokines, boosting of antibody production and formation of an antigen depot. This platform shows several advantages including easy preparation, cost-effectiveness, long life, convenience of transportation and storage, and no need for the cold chain. These findings may have promising implications for the rational design of safe and effective spore-based composite vaccine platforms.

Ru/Rh Cation Doping and Oxygen-Vacancy Engineering of FeOOH Nanoarrays@Ti3 C2 Tx MXene Heterojunction for Highly Efficient and Stable Electrocatalytic Oxygen Evolution.

Oxyhydroxides hold promise as highly-efficient non-noble electrocatalysts for the oxygen evolution reaction (OER), but their poor conductivity and structural instability greatly impede their progress. Herein, the authors develop a cation-doping and oxygenvacancy engineering strategy to fabricate Ru/Rh-doped FeOOH nanoarrays with abundant oxygen-vacancies in situ grown on Ti3 C2 Tx MXene (Ru/Rh-FeOOH@Ti3 C2 Tx ) as highly-efficient OER electrocatalysts. Benefiting from Ru/Rh-cation regulation, oxygenvacancy engineering, and heterojunction synergy between MXene and modulated FeOOH, the optimized Rh/Ru-FeOOH@Ti3 C2 Tx electrocatalysts exhibit excellent OER activities and remarkable stabilities with 100 h. Particularly, 3%Rh-FeOOH@Ti3 C2 Tx electrocatalyst only needs a 223 mV overpotential at 10 mA cm-2 and 306 mV to reach 100 mA cm-2 , which is superior to commercial IrO2 catalyst and most reported oxyhydroxide-based electrocatalysts. Further, systematically theoretical caculation, kinetics, thermodynamics, and microstructural analysis verify that the integration of Ru/Rh-cation doping and oxygen vacancy obviously enhances the intrinsic conductivity and lattice defects of FeOOH and expose more active sites, thereby decreasing the adsorption/desorption energy barrier and activation energy, and improving the specific activity and catalytic kinetics of electrocatalysts, whereas in situ hybridization with MXene strengthens the structural stability. This work clearly confirms that cationdoping and oxygen-vacancy engineering offers a joint strategy for the electronic structure modulation and design of highly-efficient inexpensive OER electrocatalysts.

Introducing the Solvent Co-Intercalation Mechanism for Hard Carbon with Ultrafast Sodium Storage.

As the most successful anode material for sodium-ion batteries, hard carbon has attracted extensive attention from researchers. However, its storage mechanism is still controversial. In this paper, a solvent co-intercalation mechanism into hard carbon is proposed and is proved by in situ XRD and ex situ TEM XPS results successfully. Thanks to the co-intercalation of solvent, the platform capacity of hard carbon maintains well at very high current densities. It can even exhibit 245 mAh g-1 at 5 A g-1 , which is the best rate performance obtained for hard carbon anode as far as it is known. The full battery assembled with Na3 V2 (PO4 )3 has a high energy density of 157 Wh kg-1 at 3800 W kg-1 (relative to the electrode). This finding brings new insights with regard to the design of hard carbon materials and sodium storage mechanisms.

Fluorination-enabled Reconstruction of NiFe Electrocatalysts for Efficient Water Oxidation.

Developing low-cost and efficient electrocatalysts to accelerate oxygen evolution reaction (OER) kinetics is vital for water and carbon-dioxide electrolyzers. The fastest-known water oxidation catalyst, Ni(Fe)OxHy, usually produced through an electrochemical reconstruction of precatalysts under alkaline condition, has received substantial attention. However, the reconstruction in the reported catalysts usually leads to a limited active layer and poorly controlled Fe-activated sites. Here, we demonstrate a new electrochemistry-driven F-enabled surface-reconstruction strategy for converting the ultrathin NiFeOxFy nanosheets into an Fe-enriched Ni(Fe)OxHy phase. The activated electrocatalyst shows a low OER overpotential of 218 ± 5 mV at 10 mA cm-2 and a low Tafel slope of 31 ± 4 mV dec-1, which is among the best for NiFe-based OER electrocatalysts. Such superior performance is caused by the effective formation of the Fe-enriched Ni(Fe)OxHy active-phase that is identified by operando Raman spectroscopy and the substantially improved surface wettability and gas-bubble-releasing behavior.

Optimizing SnO2- x /Fe2 O3 Hetero-Nanocrystals Toward Rapid and Highly Reversible Lithium Storage.

Engineering oxygen vacancy and boosting Li2 O reversibility on oxides-based electrode are of significance but remains a challenge in high-power lithium-ion batteries. Herein, the heterogenous SnO2- x /Fe2 O3- y nanocrystals are demonstrated with tailorable x and y values enabled by a glucose-assisted spray combustion technique. Density functional theory calculations unveil the SnO2- x /Fe2 O3 with a maximum x value has the optimal electronic structure, the metallic Fe generated from Fe2 O3 can markedly reduce the free energy to break Li-O bonds for accelerating subsequent delithiation process of Li2 O. Consequently, the optimized SnO2- x /Fe2 O3 exhibits a remarkably enhanced electrochemical reversibility and reaction kinetics. After stabilized by reduced graphene oxide, the hybrid delivers a high reversible specific capacity of 1113 mAh g-1 with superior rate performance (474 mAh g-1 at 20 A g-1 ) and long cycle life (negligible loss after 500 cycles at 5 A g-1 ), the oxygen vacancy and microstructure are well-maintained after cycles. This work provides the possibilities for skillfully regulating oxygen vacancy and meantime enhancing Li2 O reversibility.