Nitrogen-Rich WN Clusters with Atomic Disorders and Non-Grain Boundaries Confined in Carbon Nanosheets Boosting Sodium-Ion Storage.

Sodium-ion batteries (SIBs) as economic candidates have received considerable attention for large-scale energy storage applications. However, crystalline metal compounds with specific transport routes and rigid structures restrict their practical applications. Herein, the atomically dispersed N-rich amorphous WN clusters confined in the carbon nanosheets (WN/CNSs) are reported. Through advanced tests and calculations, the structural advantages, reaction mechanisms, and kinetic behaviors of the clusters are systematically analyzed. Compared with the crystalline W2 N with low theoretical capacity (only 209.3 mAh g-1 ), the amorphous WN clusters have the advantages of atomic disorders and non-grain boundaries and can afford abundant active sites (unsaturated dangling bonds) and isotropic charge transfer channels, which can be further enhanced by the N-rich characteristics and high electronegativity of the clusters. The encapsulation of CNSs has high conductivity and structural stability, which promotes electron transfer and effectively buffers volume expansions. As a SIB anode, the reversible capacity of WN/CNSs reaches 421.2 mAh g-1 at 0.1 A g-1 . Even at 20 A g-1 , the reversible capacity of 170.7 mAh g-1 is maintained after 8000 cycles. This study focuses on the advantages of amorphous nitrides, which have important guiding significance for the design of atomic clusters for high-performance metal ion batteries.

Tunable Surface Selenization on MoO2 -Based Carbon Substrate for Notably Enhanced Sodium-Ion Storage Properties.

Transition metal chalcogenides with high theoretical capacity are promising conversion-type anode materials for sodium ion batteries (SIBs), but often suffer from unsatisfied cycling stability (hundreds of cycles) caused by structural collapse and agglomerate. Herein, a rational strategy of tunable surface selenization on highly crystalline MoO2 -based carbon substrate is designed, where the sheet-like MoSe2 can be coated on the surface of bundle-like N-doped carbon/granular MoO2 substrate, realizing partial transformation from MoO2 to MoSe2 , and creating b-NC/g-MoO2 @s-MoSe2 -10 with robust hierarchical MoO2 @MoSe2 heterostructures and strong chemical couplings (MoC and MoN). Such well-designed architecture can provide signally improved reaction kinetics and reinforced structural integrity for fast and stable sodium-ion storage, as confirmed by the ex situ results and kinetic analyses as well as the density functional theory calculations. As expected, the b-NC/g-MoO2 @s-MoSe2 -10 delivers splendid rate capability and ultralong cycling stability (254.2 mAh g-1 reversible capacity at 5.0 A g-1 after 6000 cycles with ≈89.0% capacity retention). Therefore, the tunable surface strategy can provide new insights for designing and constructing heterostructures of transition metal chalcogenides toward high-performance SIBs.

Encapsulating N-Doped Carbon Nanorod Bundles/MoO2 Nanoparticles via Surface Growth of Ultrathin MoS2 Nanosheets for Ultrafast and Ultralong Cycling Sodium Storage.

Conversion-type anode materials possess high theoretical capacity for sodium-ion batteries (SIBs), owing to multi-electron transmission (2-6 electrons). Mo-based chalcogenides are a class of great promise, high-capacity host materials, but their development still undergoes serious volume changes and low transport kinetics during the cycling process. Here, MoO2 nanoparticles anchored on N-doped carbon nanorod bundles (N-CNRBs/MoO2) are synthesized by a facile self-polymerized route and a following annealing. After hydrothermal sulfuration, N-CNRBs/MoO2 composites are encapsulated by surface growth of ultrathin MoS2 nanosheets, acquiring hierarchical N-CNRBs/MoO2@MoS2 composites. Serving as the SIB anode, the N-CNRBs/MoO2@MoS2 electrode exhibits significantly improved sodium-ion storage properties. The reversible capacity is up to 554.4 mA h g-1 at 0.05 A g-1 and maintains 249.3 mA h g-1 even at 10.0 A g-1. During 5000 cycles, no obvious capacity decay is observed and the reversible capacities retain 334.8 mA h g-1 at 3.0 A g-1 and 301.4 mA h g-1 at 5.0 A g-1. These properties could be ascribed to the vertical encapsulation of MoS2 nanosheets on high-crystalline N-CNRBs/MoO2 substrates. The hierarchical architecture and unique heterostructure between MoO2 and MoS2 synergistically facilitate sodium-ion diffusion, relieve volume changes, and boost pseudocapacitive charge storage of N-CNRBs/MoO2@MoS2 electrode. Therefore, the rational growth of nanosheets on complex substrates shows promising potential to construct anode materials for high-performance batteries.

Connexin 43 mediates changes in protein phosphorylation in HK-2 cells during chronic cadmium exposure.

Connexin 43 (Cx43) is believed to play a role in the mechanisms of toxicity of many chemical species, include cadmium (Cd). In this study, human renal proximal tubule (HK-2) cells were exposed to Cd (1µM, 10 days). Of the 584 protein residues detected using a Phospho Explorer antibody microarray (PEX100), more than half changed their levels of phosphorylation after chronic Cd exposure. Cx43 siRNA attenuated Cd-induced apoptosis and inhibited proliferation, while also attenuating changes in the levels of phosphorylation of many protein residues. According to DAVID Bioinformatics Resources analysis and KEGG PATHWAY database, AKT signal pathway may be the important one. Focusing on the AKT pathway confirmed that Cx43 mediated increased levels of p-PTENSer380/Ser382/Thr383 and decreased levels of p-AKTThr308, p-AKTTyr326, p-ASK1Ser83, and p-p27Thr187, thereby possibly contributing to the Cd-induced apoptosis and inhibited proliferation. These results suggested that AKT pathway was the dominant pathway involved in Cx43-mediated chronic Cd toxicity.