Mitigating the Surface Reconstruction of Ni-Rich Cathode via P2-Type Mn-Rich Oxide Coating for Durable Lithium Ion Batteries.

Ni-rich materials have received widespread attention as one of the mainstream cathodes in high-energy-density lithium-ion batteries for electric vehicles. However, Ni-rich cathodes suffer from severe surface reconstruction in a high delithiation state, constraining their rate capabilities and life span. Herein, a novel P2-type NaxNi0.33Mn0.67O2 (NNMO) is rationally selected as the surficial modification layer for LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode, which undergoes a spontaneous Na+-Li+ exchange reaction to form an O2-type LixNi0.33Mn0.67O2 (LNMO) layer revealed by combining X-ray diffraction and solid-state nuclear magnetic resonance techniques. Owing to the specific oxygen stacking sequence, O2-type LNMO significantly prevents the initial layered structure of NCM811 from transforming to the spinel or rock-salt phases during cycling, thus effectively maintaining the integral surficial structure and the Li+ diffusion channels of NCM811. Eventually, the NNMO@NCM811 electrode yields enhanced thermal stability, outstanding rate performance, and long cycling stability with 80% capacity retention after 294 cycles at 200 mA g-1, and its life span is further extended to 531 cycles while enhancing the mechanical stability of the bulk material.

Ozone direct oxidation pretreatment and catalytic oxidation post-treatment coupled with ABMBR for landfill leachate treatment.

In order to treat the high concentration landfill leachate, ozone direct oxidation pretreatment and catalytic oxidation post-treatment coupled with anaerobic baffled membrane bioreactor (ABMBR) system was proposed in this study. For pretreatment, ozone direct oxidation could remarkably reduce UV254, 3D fluorescence peak value and fluorescence regional integration (FRI) of organic pollutants. For ABMBR treatment, the removal efficiencies of COD and ammonia nitrogen were 80.38% and 21.56%, respectively. Post-treatment included struvite precipitation, ozone catalytic oxidation and membrane bioreactor (MBR) treatment. Finally, the total removal efficiencies of COD and ammonia nitrogen were 91.2% and 99.4%, respectively. The chroma was remarkably decreased from 1250 times to 40 times after a series of treatments. The acids in ABMBR could be degraded by microorganisms of Proteobacteria and Chloroflexi. The cellulose and polysaccharides could be decomposed by Bacteroidetes and ketones could be decomposed by Brevundimonas in ABMBR. Electron paramagnetic resonance (EPR) analysis indicated that the hydroxyl radicals were the main reactive oxygen species during the direct ozone oxidation process, while the superoxide radicals played an important role in the ozone catalytic oxidation process.

Design, preparation, characterization, and application of MnxCu1-xOy/γ-Al2O3 catalysts in ozonation to achieve simultaneous organic carbon and nitrogen removal in pyridine wastewater.

In the process of treating high-concentration pyridine wastewater, problems such as low treatment efficiency and total nitrogen (TN) residues are always encountered. Catalytic ozonation can degrade pyridine wastewater well, and it also has the potential to remove TN. However, limited research has been conducted on the development of ozonation catalysts that can simultaneously remove the total organic carbon (TOC) and TN. Density functional theory (DFT) technology can determine the number of active components on the catalyst based on its composition; therefore, it can be used to guide the research and development of such catalysts. Here, we presented a strategy to guide the preparation of two-component Mn and Cu catalysts using DFT technology. By characterising and applying the prepared MnxCu1-xOy/γ-Al2O3 catalysts, it was confirmed that the DFT accurately predicted the changes in the active site content. The selected catalyst also achieved strong TOC and TN removal rates during the catalytic ozonation of high-concentration pyridine wastewater. A Box-Behnken design and response surface methodology was used to optimise the process conditions of catalytic ozonation and verify its stability. Under the optimal reaction conditions, the TOC and TN removal efficiencies from a 500 mg/L pyridine solution were 99.8% and 45.8%, respectively. This work indicated that the use of DFT for the design of catalytic materials was an effective method, which can provide a theoretical basis for material design and reduce the time for material screening.

Reliable Interlayer Based on Hybrid Nanocomposites and Carbon Nanotubes for Lithium-Sulfur Batteries.

The future energy needs have triggered research interest in finding novel energy storage systems with high energy density. Lithium-sulfur batteries are regarded as one of the most promising options for the next-generation energy storage applications because of their high theoretical energy and low cost. However, the electrochemical performances of lithium-sulfur batteries are seriously compromised by the polysulfide (LiPS) shuttling and the insulating nature of sulfur. To overcome these issues, novel CoNi1/3Fe2O4 (CNFO) nanoparticles uniformly covered on the carbon nanotubes are now reported as an efficient functional interlayer. Benefiting from the sufficient sulfiphilic sites of the CNFO for chemically bonding with LiPSs, as well as the conductive interconnected skeleton of carbon nanotubes, this composite material showed great enhancement on the rate capability and cycle stability of Li-S batteries. The Li-S battery using this interlayer exhibited a high initial capacity of 897 mA h g-1 and a low capacity decay of 0.063% per cycle within 250 cycles at 2 C. Meanwhile, an reversible specific capacity of 869 mA h g-1 (at 0.5 C) with high Coulombic efficiency could be obtained over 100 cycles at an elevated temperature (60 °C). We speculated that the chemical adsorption of CNFO for polysulfide-anchoring is extremely critical for the performances of Li-S batteries under high temperature.

Aliskiren for heart failure: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: To systematically review and synthesize the currently available evidence of aliskiren for the treatment of heart failure. MATERIALS AND METHODS: We systematically searched the Cochrane, Embase and PubMed databases to identify the randomized controlled trials (RCT) on the effects of aliskiren on heart failure. Data were synthesized with random effects model and presented in forest plot. Publication bias was evaluated with funnel plot. Heterogeneity was evaluated with Begg's test and Egger's test. RESULTS: Of 124 studies, 6 RCT of 9845 heart failure patients were included for meta-analysis, including 3727 patients receiving aliskiren. Compared with the controls, aliskiren did not significantly reduce the all-cause mortality (1.02 [0.91-1.14], I2 = 0%) or cardiovascular mortality (1.02 [0.88-1.17], I2 = 7.3%) of heart failure patients. Total adverse events, renal dysfunction, hypotension and hyperkalaemia were not significantly different between the aliskiren group and control group. Begg's test and Egger's test indicated low heterogeneity. Funnel plots indicated low publication bias. CONCLUSIONS: Aliskiren, either used alone or combined with standard medical therapy, does not significantly reduce the all-cause mortality or cardiovascular mortality of heart failure patients. Although aliskiren does not cause statistically higher adverse events, its adverse events may not be neglected.