Ultra-Thin Hydrogen-Organic-Framework (HOF) Nanosheets for Ultra-Stable Alkali Ions Battery Storage.

Organic frameworks-based batteries with excellent physicochemical stability and long-term high capacity will definitely reduce the cost, carbon emissions, and metal consumption and contamination. Here, an ultra-stable and ultra-thin perylene-dicyandiamide-based hydrogen organic framework (HOF) nanosheet (P-DCD) of ≈3.5 nm in thickness is developed.

Effectiveness of various COVID-19 vaccine regimens among 10.4 million patients from the National COVID Cohort Collaborative during Pre-Delta to Omicron periods - United States, 11 December 2020 to 30 June 2022.

Objective: This study reports the vaccine effectiveness (VE) of COVID-19 vaccine regimens in the United States, based on the National COVID Cohort Collaborative (N3C) database.

Methods: Data from 10.4 million adults, enrolled in the N3C from 11 December 2020 to 30 June 2022, were analyzed.

Numerical Study on the Cavitation Characteristics of Micro Automotive Electronic Pumps under Thermodynamic Effect.

In order to study the influence of thermodynamic effects on the cavitation performance of hydromechanics, the Singhal cavitation model was modified considering the influence of the thermo-dynamic effects, and the modified cavitation model was written into CFX using the CEL language. Numerical simulation of the cavitation full flow field at different temperatures (25 °C, 50 °C and 70 °C) was carried out with the automotive electronic water pump as the research object. The results show that the variation trend of the external characteristic simulation and experimental values is the same at all flow rates, and the calculation accuracy meets the subsequent cavitation demand.

Rational Design of Space-Confined Mn-Based Heterostructures with Synergistic Interfacial Charge Transport and Structural Integrity for Lithium Storage.

Manganese-based compounds are expected to become promising candidates for lithium-ion battery anodes by virtue of their high theoretical specific capacity and low conversion potential. However, their application is hindered by their inferior electrical conductivity and drastic volume variations. In this work, a unique heterostructure composed of MnO and MnS spatially confined in pyrolytic carbon microspheres (MnO@MnS/C) was synthesized through an integrated solvothermal method, calcination, and low-temperature vulcanization technology.

Harmonious Dual-Riveting Interface Induced from Niobium Oxides Coating Toward Superior Stability of Li-Rich Mn-Based Cathode.

Ni/Ni and O/O redoxs endow the Li-rich layered oxide of LiMnNiO (LMNO) with a considerable specific capacity and higher voltage. However, during the repeated de-/lithiation, the constant structure degradation initiated from transition metal ion dissolvement and oxygen escape leads to rapid capacity decay, which severely hinders the commercial application of LMNO. Herein, NbO and LiNbO are fabricated on the outside of the LMNO substrate.

MnS@N,S Co-Doped Carbon Core/Shell Nanocubes: Sulfur-Bridged Bonds Enhanced Na-Storage Properties Revealed by In Situ Raman Spectroscopy and Transmission Electron Microscopy.

Rational structure and morphology design are of great significance to realize excellent Na storage for advanced electrode materials in sodium-ion batteries (SIBs). Herein, a cube-like core/shell composite of single MnS nanocubes (≈50 nm) encapsulated in N, S co-doped carbon (MnS@NSC) with strong CSMn bond interactions is successfully prepared as outstanding anode material for SIBs. The carbon shell significantly restricts the expansion of the MnS volume in successive sodiation/desodiation processes, as demonstrated by in situ transmission electron microscopy (TEM) of one single MnS@NSC nanocube.

Si@SnS -Reduced Graphene Oxide Composite Anodes for High-Capacity Lithium-Ion Batteries.

Invited for this month's cover is the group of Weitang Yao at the Southwest University of Science and Technology. The image shows that developing low-cost and high-energy-density batteries is important for powering our city. The Si@SnS -rGO composites are good electrode materials for Li-ion batteries.

Acetylcholinesterase modified AuNPs-MoS-rGO/PI flexible film biosensor: Towards efficient fabrication and application in paraoxon detection.

A flexible acetylcholinesterase (AChE) film biosensor, based on a AuNPs-MoS-reduced graphene oxide/polyimide flexible film (rGO/PI) electrode, has been synthesized for paraoxon detection. In this study, the rGO/PI film acts as the flexible substrate and AuNPs are reduced by monolayer MoS under illumination. Transmission electron microscopy revealed that AuNPs are uniformly dispersed on the MoS-rGO/PI electrode surface with a diameter ~10nm.

Si@SnS -Reduced Graphene Oxide Composite Anodes for High-Capacity Lithium-Ion Batteries.

One of the key challenges for the development of lithium-ion batteries is the preparation of high-performance anode materials. In this paper, a micro/nanostructured Si@SnS -rGO composite is reported in which Si nanoparticles with a particle size of 30 nm are electrostatically anchored on a 3D reduced graphene oxide (rGO) network and mixed with SnS . The step-wise lithiation/delithiation of SnS provided space-constraining effects to accommodate volume expansion and particle aggregation, thereby alleviating the volume expansion of Si during cycling as well as enhancing the structural stability, whereas the rGO in the 3D network stabilized the composite.

Design and Synthesis of Double-Functional Polymer Composite Layer Coating To Enhance the Electrochemical Performance of the Ni-Rich Cathode at the Upper Cutoff Voltage.

Graphene has been implemented as a desirable additive to improve the electrochemical performance of Ni-rich cathode materials. However, it is not only hard to ensure the intimate interaction between them in practice, which may affect the surface electronic conductivity of the composite, but also a challenge to fabricate cathodes with uniform graphene coating because of its two-dimensional planar structure. Besides, the graphene coating layer is easily peeled off from the cathode material during the cycling process, especially at the upper cutoff voltage.

One-pot sonochemical synthesis of magnetite@reduced graphene oxide nanocomposite for high performance Li ion storage.

In this research, we introduce a one-pot sonochemical method for the fabrication of magnetite@reduced graphene oxide (FeO@rGO) nanocomposite as anode material for Li-ion batteries. FeO@rGO is synthesized under ultrasonic irradiations by using iron (II) salt and GO as raw materials. An in-situ oxidation-reduction occurs between GO and Fe during the ultrasonic chemical reaction process.

Self-assembly of red-blood-cell-like (NH)[Fe(OH)(PO)]·2HO architectures from 2D nanoplates by sonochemical method.

Red-blood-cell-like (RBC-like) (NH)[Fe(OH)(PO)]·2HO architectures assembled from 2D nanoplates are successfully synthesized via a facile sonochemical method. XRD measurement indicates that the as-prepared sample is well crystallized with a monoclinic structure. The morphology of the sample is characterized by SEM analysis, which shows that the (NH)[Fe(OH)(PO)]·2HO particles exhibit a unique biconcave red blood cell morphology with an average diameter of 4um and thickness of 1.