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Layered oxides as the cathode materials of sodiumion batteries are receiving extensive attention due to their high capacity and flexible composition. However,t he layered cathode tends to be thermodynamically and electrochemically unstable during (de)sodiation. Herein, we propose the pinning effect and controllable pinning point in sodium storage layered cathodes to enhance the structural stability and achieve optimal electrochemical performance.0%, 2.5 %and 7.3 %transitionmetal occupancies in Na-site as pinning points are obtained in Na 0.67 Mn 0.5 Co 0.5Àx Fe x O 2 .2 .5 %N a-site pinned by Fe 3+ is beneficial to restrain the potential slab sliding and enhance the structural stability,r esulting in an ultra-low volume variation of 0.6 %a nd maintaining the smooth two-dimensional channel for Na-ion transfer.The Na 0.67 Mn 0.5 Co 0.4 Fe 0.1 O 2 cathode with the optimal Fe 3+ pinning delivers outstanding cycle performance of over 1000 cycles and superior rate capability up to 10 C.

Bi2O2Se, a high‐mobility and air‐stable 2D material, has attracted substantial attention for application in integrated logic electronics and optoelectronics. However, achieving an overall high performance over a wide spectral range for Bi2O2Se‐based devices remains a challenge. A broadband phototransistor with high photoresponsivity (R) is reported that comprises high‐quality large‐area (≈180 µm) Bi2O2Se nanosheets synthesized via a modified chemical vapor deposition method with a face‐down configuration. The device covers the ultraviolet (UV), visible (Vis), and near‐infrared (NIR) wavelength ranges (360–1800 nm) at room temperature, exhibiting a maximum R of 108 696 A W−1 at 360 nm. Upon illumination at 405 nm, the external quantum efficiency, R, and detectivity (D*) of the device reach up to 1.5 × 107%, 50055 A W−1, and 8.2 × 1012 Jones, respectively, which is attributable to a combination of the photogating, photovoltaic, and photothermal effects. The devices reach a −3 dB bandwidth of 5.4 kHz, accounting for a fast rise time (τrise) of 32 µs. The high sensitivity, fast response time, and environmental stability achieved simultaneously in these 2D Bi2O2Se phototransistors are promising for high‐quality UV and IR imaging applications.

Sodium layered oxides are considered to be cathode candidates with the most potential for large-scale energy storage because of their high reversible capacity and wide availability of sodium resources. A significant hurdle to wide application of these layered oxides lies in simultaneously satisfying high-energy density and long cycle life because of the intrinsic problems associated with their structural irreversibility. Herein, a O3/O′3-P2 core–shell composite that integrates a high specific capacity from O-type Ni-based core and good structural stability from P2-type Mn-rich shell is presented. Multiscale electron microscopy and affiliated spectroscopy analyses reveal that, in addition to the microscale O3/O′3-P2 core–shell structure, a nanoscale coherent P2/O3 intergrown structure can also be identified in the composite. Such well-tailored structures not only constrain the structural damages (microscale cracks) induced by repeated volumetric changes upon desodiation and resodiation but also facilitate fast Na ions diffusion through the exterior P2-type layered structure. This work may provide new clues into the design of high-performance cathode materials for sodium-ion batteries.

ABSTRACT:Particulate platforms capable of delivering multiple actives while providing diagnostic features have gained considerable interest over the last few years. In this study, magnetic polymer yolkshell particles (YSPs) were engineered using a tri-needle coaxial electrospraying technique enabling dual-mode (ultrasonic and magnetic resonance) imaging capability with specific multidrug compartments via an advanced single-step encapsulation process. YSPs comprised magnetic Fe 3 O 4 nanoparticles (MNPs) embedded in the polymeric shell, an interfacing oil layer and a polymeric core (i.e. composite shell-oil interface-polymeric core). Ultrasound backscatter signal frequency was modulated through YSP loading dosage, and both T 1 and T 2 weighted MRI signal intensities were shown to reduce with increasing MNP content (YSP outer shell). Three fluorescent dyes (selected as model probes with varying hydrophobicities) were co-encapsulated separately to confirm YSP structure. Probe release profiles were tuned by varying power or frequency of an external auxillary magnetic field (AMF, 0.7 mT (LAMF) or 1.4 mT (HAMF)).In addition, an "inversion" phenomenon for AMF-enhanced drug release process was captured and is reported. Low YSP cytotoxicity (5mg/ml) and biocompatibility (murine, L929) was confirmed. In summary, magnetic YSPs demonstrate timely potential as multifunctional theranostic agents for dual-imaging modality and magnetically controlled co-active delivery.

All‐solid‐state thin film lithium batteries (TFBs) are proposed as the ideal power sources for microelectronic devices. However, the high‐temperature (>500 °C) annealing process of cathode films, such as LiCoO2 and LiMn2O4, restricts the on‐chip integration and potential applications of TFBs. Herein, tunnel structured LixMnO2 nanosheet arrays are fabricated as 3D cathode for TFBs by a facile electrolyte Li+ ion infusion method at very low temperature of 180 °C. Featuring an interesting tunnel intergrowth structure consisting of alternating 1 × 3 and 1 × 2 tunnels, the LixMnO2 cathode shows high specific capacity with good structural stability between 2.0 and 4.3 V (vs. Li+/Li). By utilizing the 3D LixMnO2 cathode, all‐solid‐state LixMnO2/LiPON/Li TFB (3DLMO‐TFB) has been successfully constructed with prominent advantages of greatly enriched cathode/electrolyte interface and shortened Li+ diffusion length in the 3D structure. Consequently, the 3DLMO‐TFB device exhibits large specific capacity (185 mAh g−1 at 50 mA g−1), good rate performance, and excellent cycle performance (81.3% capacity retention after 1000 cycles), outperforming the TFBs using spinel LiMn2O4 thin film cathodes fabricated at high temperature. Importantly, the low‐temperature preparation of high‐performance cathode film enables the fabrication of TFBs on various rigid and flexible substrates, which could greatly expand their potential applications in microelectronics.

The composite AgOx/NiOx electrocatalyst was found to possess both kinetic and thermodynamic functions.

Topography and surface morphology of micrometer and nanometer scaled fibrous biomaterials are crucial for bioactive component encapsulation, release, promoting cell proliferation and interaction within biological environment. Specifically, for drug delivery and tissue repair applications, surface engineering provides control on both aspects in tandem. In this study, the bioactive component (ganoderma lucidum spore polysaccharide (GLSP)) was loaded into zein prolamine (ZP) fiber matrices via coaxial electrospinning (CES) technique. During the CES process, various outer layer enveloping fluids were used to modulate fiber topography in-situ (from 2D to 3D). SEM and water contact angle tests indicate enveloping media impact electrospun fiber diameter (ranging from 400 nm to 3.0 μm) and morphologies (from flat ribbon-like to solid cylindrical structures), with the latter impacting GLSP release profile. Furthermore, CCK-8 assay assessment indicates fibroblast cell proliferation (L929 cell line), while cell extension was also observed for modified ZP fibers. The results demonstrate potential applications of modified fiber morphologies, which are tailored in-situ without impacting chemical stability and encapsulation.