Hybrid Interface Chemistry Enabling Mixed Conducting via Ultrafast Microwave Polarization Toward Dendrite-Free Zn Anodes.

Zn metal anodes in aqueous electrolytes suffer from interface issues including uncontrolled dendrite growth and undesired side reactions, resulting in their limited application in terms of short circuits and cell failure. Herein, a hybrid interface chemistry strategy is developed through ultrafast microwave polarization at the skin region of bare Zn. Owing to efficient Joule heating directed by abundant local hot spots at electron valleys, the rapid establishment of a dense interfacial layer can be realized within a minute. Stabilized Zn with suppressed side reactions or surface corrosion is therefore achieved due to the interfacial protection. Importantly, hybrid zincophilic sites involving laterally/vertically interconnected Cu-Zn intermetallic compound and Zn2+ -conductive oxide species ensure mixed charge conducting (denoted as CuHL@Zn), featuring uniformly distributed electric field and boosted Zn2+ diffusion kinetics. As a consequence, CuHL@Zn in symmetric cells affords lifespans of 2800 and 3200 h with ultra-low polarization voltages (≈19 and 56 mV) at a plating capacity of 1.0 mAh cm-2 for 1 and 5 mA cm-2 , respectively. The CuHL@Zn||MnO2 full cell further exhibits cycling stability with a capacity retention of over 80% for 500 cycles at 2 A g-1 .

Axial Chlorine Induced Electron Delocalization in Atomically Dispersed FeN4 Electrocatalyst for Oxygen Reduction Reaction with Improved Hydrogen Peroxide Tolerance.

Atomically dispersed iron sites on nitrogen-doped carbon (Fe-NC) are the most active Pt-group-metal-free catalysts for oxygen reduction reaction (ORR). However, due to oxidative corrosion and the Fenton reaction, Fe-NC catalysts are insufficiently active and stable. Herein, w e demonstrated that the axial Cl-modified Fe-NC (Cl-Fe-NC) electrocatalyst is active and stable for the ORR in acidic conditions with high H2 O2 tolerance. The Cl-Fe-NC exhibits excellent ORR activity, with a high half-wave potential (E1/2 ) of 0.82 V versus a reversible hydrogen electrode (RHE), comparable to Pt/C (E1/2 = 0.85 V versus RHE) and better than Fe-NC (E1/2 = 0.79 V versus RHE). X-ray absorption spectroscopy analysis confirms that chlorine is axially integrated into the FeN4. More interestingly, compared to Fe-NC, the Fenton reaction is markedly suppressed in Cl-Fe-NC. In situ electrochemical impedance spectroscopy reveals that Cl-Fe-NC provides efficient electron transfer and faster reaction kinetics than Fe-NC. Density functional theory calculations reveal that incorporating Cl into FeN4 can drive the electron density delocalization of the FeN4 site, leading to a moderate adsorption free energy of OH* (∆GOH* ), d-band center, and a high onset potential, and promotes the direct four-electron-transfer ORR with weak H2 O2 binding ability compared to Cl-free FeN4, indicating superior intrinsic ORR activity.

Using different machine learning models to classify patients into mild and severe cases of COVID-19 based on multivariate blood testing.

COVID-19 is a serious respiratory disease. The ever-increasing number of cases is causing heavier loads on the health service system. Using 38 blood test indicators on the first day of admission for the 422 patients diagnosed with COVID-19 (from January 2020 to June 2021) to construct different machine learning (ML) models to classify patients into either mild or severe cases of COVID-19. All models show good performance in the classification between COVID-19 patients into mild and severe disease. The area under the curve (AUC) of the random forest model is 0.89, the AUC of the naive Bayes model is 0.90, the AUC of the support vector machine model is 0.86, and the AUC of the KNN model is 0.78, the AUC of the Logistic regression model is 0.84, and the AUC of the artificial neural network model is 0.87, among which the naive Bayes model has the best performance. Different ML models can classify patients into mild and severe cases based on 38 blood test indicators taken on the first day of admission for patients diagnosed with COVID-19.

Molecular Bridging Enables Isolated Iron Atoms on Stereoassembled Carbon Framework To Boost Oxygen Reduction for Zinc-Air Batteries.

Realizing the synergy between active site regulation and rational structural engineering is essential in the electrocatalysis community but still challenging. Here, a matrix-confined co-pyrolysis strategy based on molecular bridging is demonstrated to realize highly dispersed Fe atoms on stereoassembled carbon framework. Both polyacrylonitrile matrix and organic linker from metal-organic frameworks (MOFs) provide sufficient N-anchoring sites for the generation of Fe-N4 moieties. A high Fe loading of 2.9 wt.% is readily achieved based on the scalable approach without post-treatment. Owing to the presence of highly exposed Fe-N-C sites and well-tuned pore structures, isolated Fe atoms on porous carbon nanofiber framework (Fe-SA/NCF) exhibits decent oxygen reduction activity and stability in alkaline conditions via a near four-electron path, demonstrating superior performance as air cathode for zinc-air batteries (ZABs) to commercial Pt/C catalyst.

An Oxidant- and Catalyst-Free Electrooxidative Cross-Coupling Approach to Synthesize meso-Substituted Porphyrin Derivatives.

The synthesis of porphyrin and chlorin derivatives has attracted significant attention due to their numerous applications. Herein, we report an environment friendly oxidant- and catalyst-free electrooxidative cross-coupling approach for multiple coupling reactions to synthesize meso C-N, C-O, and C-S substituted porphyrin and chlorin derivatives. For C-N cross-coupling reactions, diaminated porphyrins were obtained as the main products, while using 4-bromo-2,6-dimethyl aniline resulted in monoaminated product. Similarly, electrochemical catalysis of porphyrins with phenol and thiophene produced meso-disubstituted porphyrins in moderate yields under a smaller current. Chlorins were also applicable, and 20-substituted products were efficiently produced regioselectively. To the best of our knowledge, this work represents the first example of electrooxidative C-X cross-coupling of porphyrins and chlorins.

Discovery of sertraline and its derivatives able to combat drug-resistant gastric cancer cell via inducing apoptosis.

Resistance phenomena during chemotherapy of tumor has been severely hampering the applications of chemotherapeutics. Due to advantage of drug repurposing, discovery of new chemosensitizers based on approved drugs is an effect strategy to find new candidates. Herein, we found antidepressant drug - sertraline, could sensitize drug-resistant gastric cancer cell (SGC-7901/DDP) with the IC50 value of 18.73 µM. To understand the structure-activity relationship and improve the activity, 30 derivatives were synthesized and evaluated. The IC50 value of the best compound was improved to 5.2 µM. Moreover, we found apoptosis induction and cell cycle arrest was the reason for the cell death of the drug-resistant cells after treatment of sertraline and derivatives, and PI3K/Akt/mTOR pathway was involved.

Ultrafast Microwave Activating Polarized Electron for Scalable Porous Al toward High-Energy-Density Batteries.

Chemical etching of metals generally brings about undesirable surface damage accompanied by deteriorated performance. However, new possibilities in view of structured interfaces and functional surfaces can be explored by wisely incorporating corrosion chemistry. Here, an ultrafast route to scalable Al foils with desired porous structures originating from Fe(III)-induced oxidation etching was presented. Coupling with efficient electron polarization involving microwave interaction, straightforward surface engineering is well established on various commercial Al foils within minutes, which can be successfully extended to bulk Al alloys. As a proof-of-concept demonstration, the well-defined porous Al foils featuring regulated surface energy, demonstrate great potential as current collectors in promoting cycling stability, for example, 85.2% reversible capacity sustained after 550 cycles (comparable to commercial Al/C foils), and energy density, that is, approximately 3 times of that by using pristine Al foils for LiFePO4-Li half cells.

Direct Hybridization of Noble Metal Nanostructures on 2D Metal-Organic Framework Nanosheets To Catalyze Hydrogen Evolution.

Rational hybridization of two-dimensional (2D) nanomaterials with extrinsic species has shown great promise for a wide range of applications. To date, rational design and engineering of heterostructures based on 2D metal-organic frameworks (MOFs) has been rather limited. Herein, we report an efficient strategy to construct noble metal/2D MOF heterostructures, featuring the utilization of surface oxygen sites from uncoordinated MOF ligands. The incorporation of highly dispersed noble metal nanoparticles (e.g., Pt and Pd) with modulated electronic structure is enabled on a surfactant-free MOF surface. As a proof-of-concept demonstration, the 2D Ni-MOF@Pt hybrid with well-defined interfaces is applied to boost the electrochemical hydrogen evolution reaction (HER) and delivers decent electrocatalytic activity under both acidic and alkaline conditions. The present results are expected to provide new insights into furnishing MOFs with extended functionalities and applications.

Rational Design of a Flexible CNTs@PDMS Film Patterned by Bio-Inspired Templates as a Strain Sensor and Supercapacitor.

Flexible devices integrated with sensing and energy storage functions are highly desirable due to their potential application in wearable electronics and human motion detection. Here, a flexible film is designed in a facile and low-cost leaf templating process, comprising wrinkled carbon nanotubes (CNTs) as the conductive layer and patterned polydimethylsiloxane (PDMS) with bio-inspired microstructure as a soft substrate. Assembled from wrinkled CNTs on patterned PDMS film, a strain sensor is realized to possess sensitive resistance response against various deformations, producing a resistance response of 0.34%, 0.14%, and 9.1% under bending, pressing, and 20% strain, respectively. Besides, the strain sensor can reach a resistance response of 3.01 when stretched to 44%. Furthermore, through the electro-deposition of polyaniline, the CNTs film is developed into a supercapacitor, which exhibits a specific capacitance of 176 F g-1 at 1 A g-1 and a capacitance retention of 88% after 10 000 cycles. In addition, the fabricated supercapacitor shows super flexibility, delivering a capacitance retention of 98% after 180° bending for 100 cycles, 95% after 45° twisting for 100 cycles, and 98% after 100% stretching for 400 cycles. The superior capacitance stability demonstrates that the design of wrinkled CNTs-based electrodes fixed by microstructures is beneficial to the excellent electrochemical performance.

Nitrogen Boosts Defective Vanadium Oxide from Semiconducting to Metallic Merit.

2D metal oxide nanosheets have attracted substantial attention for various applications owing to their appealing advantages. Yet, the exploration of effective methodology for fabrication of metallic 2D metal oxides with a high concentration of N dopants in a scalable manner remains challenging. Herein, a topochemical strategy is demonstrated on vanadium oxide nanosheets by combining 2D nanostructuring, heteroatom-doping, and defect engineering for modulating their intrinsic electronic structure and greatly enhancing their electrochemical property. O vacancies and N dopants (VON and VN bonds) are in situ formed in vanadium oxide via nitridation and lead to semiconductive-to-metallic phase transformation evidenced by experimental results and theoretical calculation. Overall, the N-VO0.9 nanosheets exhibit a metallic electron transportation behavior and excellent electrochemical performance. These findings shed light on the rational design and electron structure tuning of 2D nanostructures for energy and electronics applications.

Recent Progress on Nickel-Based Oxide/(Oxy)Hydroxide Electrocatalysts for the Oxygen Evolution Reaction.

Developing clean and sustainable energies as alternatives to fossil fuels is in strong demand within modern society. The oxygen evolution reaction (OER) is the efficiency-limiting process in plenty of key renewable energy systems, such as electrochemical water splitting and rechargeable metal-air batteries. In this regard, ongoing efforts have been devoted to seeking high-performance electrocatalysts for enhanced energy conversion efficiency. Apart from traditional precious-metal-based catalysts, nickel-based compounds are the most promising earth-abundant OER catalysts, attracting ever-increasing interest due to high activity and stability. In this review, the recent progress on nickel-based oxide and (oxy)hydroxide composites for water oxidation catalysis in terms of materials design/synthesis and electrochemical performance is summarized. Some underlying mechanisms to profoundly understand the catalytic active sites are also highlighted. In addition, the future research trends and perspectives on the development of Ni-based OER electrocatalysts are discussed.

Iron-Doped Nickel Molybdate with Enhanced Oxygen Evolution Kinetics.

Electrochemical water splitting is one of the potential approaches for making renewable energy production and storage viable. The oxygen evolution reaction (OER), as a sluggish four-electron electrochemical reaction, has to overcome high overpotential to accomplish overall water splitting. Therefore, developing low-cost and highly active OER catalysts is the key for achieving efficient and economical water electrolysis. In this work, Fe-doped NiMoO4 was synthesized and evaluated as the OER catalyst in alkaline medium. Fe3+ doping helps to regulate the electronic structure of Ni centers in NiMoO4 , which consequently promotes the catalytic activity of NiMoO4 . The overpotential to reach a current density of 10 mA cm-2 is 299 mV in 1 m KOH for the optimal Ni0.9 Fe0.1 MoO4 , which is 65 mV lower than that for NiMoO4 . Further, the catalyst also shows exceptional performance stability during a 2 h chronopotentiometry testing. Moreover, the real catalytically active center of Ni0.9 Fe0.1 MoO4 is also unraveled based on the ex situ characterizations. These results provide new alternatives for precious-metal-free catalysts for alkaline OER and also expand the Fe-doping-induced synergistic effect towards performance enhancement to new catalyst systems.

Coaxial-cable hierarchical tubular MnO2@Fe3O4@C heterostructures as advanced anodes for lithium-ion batteries.

Nanostructured manganese oxides have been regarded as promising anodes for lithium-ion batteries (LIBs) due to their high specific capacity, environmental friendliness and low cost. However, as conversion-type electrodes, their scalable utilization is hindered by intrinsically low reaction kinetics, large volume variation and high polarization. Herein, a coaxial-cable tubular heterostructure composed of a hollow carbon skeleton, Fe3O4 nanoparticles and ultrathin MnO2 nanosheets from inside out, donated as MnO2@Fe3O4@C, is synthesized via a facile two-step hydrothermal process. The unique design integrates conductive carbon and nanostructured MnO2 and Fe3O4 into a one-dimensional (1D) hierarchically open architecture, which provides abundant electrode-electrolyte contact areas, favorable heterointerfaces and ultrafast electron/ion pathways. Benefiting from these features, the MnO2@Fe3O4@C anode exhibits a high reversible capacity of 946 mAh g-1 at 200 mA g-1 after 160 cycles, and excellent cyclability with a specific capacity of 845 mAh g-1 at 500 mA g-1 after 600 cycles. This work might provide an insightful guideline for the design of novel electrode materials.

Platinum/Nickel Bicarbonate Heterostructures towards Accelerated Hydrogen Evolution under Alkaline Conditions.

Heterostructured nanomaterials, generally have physicochemical properties that differ from those of the individual components, and thus have potential in a wide range of applications. New platinum (Pt)/nickel bicarbonate (Ni(HCO3 )2 ) heterostructures are designed for an efficient alkaline hydrogen evolution reaction (HER). Notably, the specific and mass activity of Pt in Pt/Ni(HCO3 )2 are substantially improved compared to the bare Pt nanoparticles (NPs). The Ni(HCO3 )2 provides abundant water adsorption/dissociation sites and modulate the electronic structure of Pt, which determine the elementary reaction kinetics of alkaline HER. The Ni(HCO3 )2 nanoplates offer a platform for the uniform dispersion of Pt NPs, ensuring the maximum exposure of active sites. The results demonstrate that, Ni(HCO3 )2 is an effective catalyst promoter for alkaline HER.

Stereoselectively Assembled Metal-Organic Framework (MOF) Host for Catalytic Synthesis of Carbon Hybrids for Alkaline-Metal-Ion Batteries.

Cost-effective metal-based nanostructured hybrids have been widely dedicated to potential energy storage and conversion applications. Herein, we develop a facile methodology for the synthesis of precise carbon-confined hybrid nanostructures by stereoselective assembly accompanied by catalytic pyrolysis. Polyacrylonitrile fiber films favors not only metal-polymer coordination, but also oriented assembly to ensure the well-defined nanostructure of the carbon hybrids. During chemical vapor deposition (CVD), cobalt-nanoparticle-catalyzed growth of carbon-nanotube branches driven by organic molecules (e.g. melamine) delivers hierarchical carbon hybrids. The resulting carbon hybrids exhibit outstanding electrochemical performance for metal-ion batteries, for example, a high specific capacity of 680 mAh g-1 after 320 cycles (Li-storage) and 220 mAh g-1 after 500 cycles (Na-storage) without decay.

Low-Coordinate Iridium Oxide Confined on Graphitic Carbon Nitride for Highly Efficient Oxygen Evolution.

Highly active and durable electrocatalysts for the oxygen evolution reaction (OER) is greatly desired. Iridium oxide/graphitic carbon nitride (IrO2 /GCN) heterostructures are designed with low-coordinate IrO2 nanoparticles (NPs) confined on superhydrophilic highly stable GCN nanosheets for efficient acidic OER. The GCN nanosheets not only ensure the homogeneous distribution and confinement of IrO2 NPs but also endows the heterostructured catalyst system with a superhydrophilic surface, which can maximize the exposure of active sites and promotes mass diffusion. The coordination number of Ir atoms is decreased owing to the strong interaction between IrO2 and GCN, leading to lattice strain and increment of electron density around Ir sites and hence modulating the attachment between the catalyst and reaction intermediates. The optimized IrO2 /GCN heterostructure delivers not only by far the highest mass activity among the reported IrO2 -based catalysts but also decent durability.

Carbon Necklace Incorporated Electroactive Reservoir Constructing Flexible Papers for Advanced Lithium-Ion Batteries.

Metal-organic frameworks (MOFs) and their derivatives with well-defined structures and compositions show great potential for wide applications such as sensors, catalysis, energy storage, and conversion, etc. However, poor electric conductivity and large volume expansion are main obstacles for their utilization in energy storage, e.g., lithium-ion batteries and supercapacitors. Herein, a facile strategy is proposed for embedding the MOFs, e.g., ZIF-67 and MIL-88 into polyacrylonitrile fibers, which is further used as a template to build a 3D interconnected conductive carbon necklace paper. Owing to the unique structure features of good electric conductivity, interconnected frameworks, electroactive reservoir, and dual dopants, the obtained flexible electrodes with no additives exhibit high specific capacities, good rate capability, and prolonged cycling stability. The hollow dodecahedral ZIF-67 derived carbon necklace paper delivers a high specific capacity of 1200 mAh g-1 and superior stability of more than 400 cycles without capacity decay. Moreover, the spindle-like MIL-88 derived carbon necklace paper shows a high reversible capacity of 980 mAh g-1 . Their unique 3D interconnected structure and outstanding electrochemical performance pave the way for extending the MOF-based interweaving materials toward potential applications in portable and wearable electronic devices.

CoSe2 /MoSe2 Heterostructures with Enriched Water Adsorption/Dissociation Sites towards Enhanced Alkaline Hydrogen Evolution Reaction.

Transition-metal dichalcogenides (TMDs) are promising electrocatalysts toward the hydrogen evolution reaction (HER) in acid media, but they show significantly inferior activity in alkaline media due to the extremely sluggish water dissociation kinetics. Herein, CoSe2 /MoSe2 heterostructures with CoSe2 quantum dots anchored on MoSe2 nanosheets are synthesized towards enhanced alkaline HER catalytic activity. The incorporation of CoSe2 is intended to construct additional water adsorption sites on the basal planes of MoSe2 to promote water dissociation. The CoSe2 /MoSe2 heterostructures show substantially enhanced activity over MoSe2 and CoSe2 in 1 m KOH. The optimal overpotential required to reach a current density of 10 mA cm-2 is merely 218 mV, which is more than 100 mV greater than that of MoSe2 , which is by far the best performance demonstrated for precious-metal-free catalysts. Detailed analyses based on electrochemical testing demonstrate that the water adsorption and subsequent dissociation process is accelerated by CoSe2 species with rich edge sites; meanwhile, MoSe2 species provide sufficient active sites for the adsorption and combination of adsorbed hydrogen (H. ). These results provide an effective strategy for developing earth-abundant catalysts with high activity for the alkaline HER, and are of great significance to promote the practical application of alkaline water electrolysis.

[Association of Serum Soluble CD36 with Clinical Variables in Diabetic Patients with Chronic Kidney Diseas].

OBJECTIVE: To investigate the levels of serum soluble CD36 (sCD36) in patients of diabetes mellitus (DM) with chronic kidney disease (CKD),and to analyze its correlation with clinical indicators. METHODS: A total of 161 patients with CKD were enrolled in this study. The patients were divided into two groups according to whether they had DM or not: DM+CKD group and non-DM CKD group. The levels of carotid intima-media thickness (IMT) and the combination of atherosclerotic plaques were measured by color Doppler ultrasonography. Serum fasting serum samples were collected and serum sCD36 level was measured by ELISA. the status of serum sCD36 was analyzed with the progress of renal disease,and the correlation of sCD36 level with clinical indicators were analyzed. RESULTS: Among the 161 patients,87 (54%) were DM+CKD and 74 (46%) were non-DM CKD. There was no significant difference in the levels of urea nitrogen (BUN),serum creatinine (sCr),estimated glomerular filtration rate (eGFR),cystatin C (Cys-C),triglyceride (TG),cholesterol (Chol),low density lipoprotein-chol (LDL-C),urinary albumin/creatinine and IMT in the two groups (P>0.05). Compared with non-DM CKD group,the serum sCD36 level (U/L) in DM+CKD group was lower (4.58±1.06 vs. 4.97±1.28,P<0.05). In DM+CKD group,serum sCD36 was negatively correlated with BUN,sCr and Cys-C (r=⁻0.355,⁻0.336,⁻0.323; P<0.01),and positively correlated with eGFR (r= 0.399; P<0.01),but not with TG,Chol,LDL-C or IMT (P>0.05). In non-DM CKD group,there was a positive correlation between sCD36 and TG,Chol and LDL-C (r= 0.251, 0.298, 0.292; P<0.05),and negatively correlated with Cys-C (r=⁻0.287; P<0.05),but not with eGFR,BUN,sCr or IMT (P>0.05). With the progress of CKD,serum sCD36 levels gradually decreased (P>0.05). CONCLUSION: Serum sCD36 level is associated with renal function in the patients with DM complicated with CKD,but not with lipid indicators.

Topochemical Synthesis of 2D Carbon Hybrids through Self-Boosting Catalytic Carbonization of a Metal-Polymer Framework.

Two-dimensional (2D) carbon hybrids have promise in various areas such as energy storage and catalysis. Simple methods for controllable fabrication of 2D graphitic carbon hybrids in a scalable manner remains challenging. Now, a microwave-assisted strategy for mass production of 2D carbon hybrids based on self-boosting catalytic carbonization of a metal-agarose framework is demonstrated. Hybrids including hollow Fe3 C nanoparticles, Ni/Co nanoparticles, and hollow FeOx nanoparticles uniformly embedded in 2D graphitic carbon nanosheets (GCNs) are obtained, demonstrating the generality of the approach. Metal-polymer coordination and microwave-enabled fast catalytic decomposition of precursors play vital roles in facilitating the formation of the nanosheet structure. The resulting FeOx -GCNs hybrid exhibits superior lithium-storage performance (1118 mAh g-1 at 500 mA g-1 and 818 mAh g-1 at 2000 mA g-1 after 1200 cycles).