Suppression of Vanadium Oxide Dissolution via Cation Metathesis within a Coordination Supramolecular Network for Durable Aqueous Zn-V2 O5 Batteries.

Aqueous zinc metal batteries (ZMBs) are a promising sustainable technology for large-scale energy storage applications. However, the water is often associated with problematic parasitic reactions on both anode and cathode, leading to the low durability and reliability of ZMBs. Here, a multifunctional separator for the Zn-V2 O5 batteries by growing the coordination supramolecular network (CSN:Zn-MBA, MBA = 2-mercaptobenzoic acid) on the conventional non-woven fabrics (NWF) is developed. CSN tends to form a stronger coordination bond as a softer cation, enabling a thermodynamically preferred Zn2+ to VO2 + substitution in the network, leading to the formation of VO2 -MBA interface, that strongly obstructs the VO2 (OH)2 - penetration but simultaneously allows Zn2+ transfer. Moreover, Zn-MBA molecules can adsorb the OTF- and distribute the interfacial Zn2+ homogeneous, which facilitate a dendrite-free Zn deposition. The Zn-V2 O5 cells with Zn-MBA@NWF separator realize high capacity of 567 mAh g-1 at 0.2 A g-1 , and excellent cyclability over 2000 cycles with capacity retention of 82.2% at 5 A g-1 . This work combines the original advantages of the template and new function of metals via cation metathesis within a CSN, provides a new strategy for inhibiting vanadium oxide dissolution.

A Two-Dimensional Porphyrin Coordination Supramolecular Network Cathode for High-Performance Aqueous Dual-Ion Battery.

Iodine has great potential in the energy storage, but high solubility of I3 - has seriously delayed its promotion. Benefited from abundant active sites and the open channel, two-dimensional coordination supramolecular networks (2D CSNs) is considered to be a candidate for the energy storage. Herein, a 2D porphyrin-CSN cathode named Zn-TCPP for aqueous iodine dual-ion battery (DIB) shows an excellent specific capacity of 278 mAh g-1 , and a high energy density of 340 Wh kg-1 at 5 A g-1 , as well as a durable cycle performance of 5000 cycles and a high Coulombic efficiency of 98 %. Molecular orbital theory, UV/VIS, Raman spectroscopy and density functional theory (DFT) calculations reveal charge-transfer interaction between the donor of porphyrin nitrogen and the acceptor of I3 - , and computational fluid dynamics (CFD) simulations demonstrate the contribution of 2D layered network structure of Zn-TCPP to the penetration of I3 - .

Anchoring I3- via Charge-Transfer Interaction by a Coordination Supramolecular Network Cathode for a High-Performance Aqueous Dual-Ion Battery.

Iodine is considered to have broad application prospects in the field of electrochemical energy storage. However, the high solubility of I3- severely hampers its practical application, and the lack of research on the anchoring mechanism of I3- has seriously hindered the development of advanced cathode materials for iodine batteries. Herein, based on the molecular orbital theory, we studied the charge-transfer interaction between the acceptor of I3- with a σ* empty antibonding orbital and the donor of pyrimidine nitrogen with lone-pair electrons, which is proved by the results of UV-vis absorption spectroscopy, Raman spectroscopy, and density functional theory (DFT) calculations. The prepared dual-ion battery (DIB) exhibits a high voltage platform of 1.2 V, a remarkable discharge-specific capacity of up to 207 mAh g-1, and an energy density of 233 Wh kg-1 at a current density of 5 A g-1, as well as outstanding cycle stability (operating stably for 5000 cycles) with a high Coulombic efficiency of 97%, demonstrating excellent electrochemical performance and a promising prospect in stationary energy storage.

Constructing Hydrophobic Interface with Close-Packed Coordination Supramolecular Network for Long-Cycling and Dendrite-Free Zn-Metal Batteries.

Commercialization of aqueous zinc-metal batteries remains unrealistic due to the substantial dendrite growth and side reaction issues on the zinc anodes. It is highly demanded to develop easy-to-handle approaches for constructing stable, dense, as well as homogeneous solid anode/electrolyte interfaces. Herein, the authors construct the zinc anode interface with a close-packed Zn-TSA (TSA = thiosalicylate) coordination supramolecular network through the facile and up-scalable wet-chemical method. The hydrophobic Zn-TSA network can block solvated water and establish a solid-state diffusion barrier to well-distribute the interfacial Zn2+ , thus inhibiting hydrogen evolution and zinc dendrite growth on the anode. Meanwhile, the Zn-TSA network induces the formation of a uniform and stable solid electrolyte interphase composed of multiple inorganic-organic compounds. This denser structure can accommodate and self-heal the crack/degradation of the anode interphase associated with the repeated volume changes, and suppress the generation of detrimental by-product, Znx (OTF- )y (OH)2x-y ·nH2 O. Such a rationally fabricated anode/electrolyte interface further endows the assembled symmetric cells with superior plating/stripping stability for over 2000 h without dendrite formation (at 1 mA cm-2 and 1 mAh cm-2 ). Furthermore, this zinc anode has practical application in the Zn-MoS2 and Zn-V2 O5 full cells. This study provides a new train of thought for constructing the dense interface of zinc-metal anode.

A nano interlayer spacing and rich defect 1T-MoS2 as cathode for superior performance aqueous zinc-ion batteries.

Aqueous Zn-ion batteries (ZIBs) are considered very promising alternatives to lithium-ion batteries. However, the low reversibility and slow diffusion of zinc ions in the positive electrode limit their commercial applications. Herein, we successfully prepared the metallic 1T phase of MoS2 (1T-MoS2) with a nano interlayer spacing of 1.025 nm through a simple one-step hydrothermal method, and used it as a cathode in ZIBs. By adjusting the hydrothermal temperature, the crystallinity and Zn2+ storage capacity of MoS2 as a cathode for ZIBs are effectively improved. MoS2 had the most favorable structure when the hydrothermal temperature was 200 °C, such as larger layer spacing and more lattice distortion. When employed as a cathode, 200-MoS2 exhibited a considerable specific capacity of 125 mA h g-1 at the current density of 2 A g-1 and high capacity retention of 100% after 500 cycles. This strategy provides a new option for improving the performance of the layered structure as an aqueous zinc ion battery.

Epitaxial growth of multiwall carbon nanotube from stainless steel substrate and effect on electrical conduction and field emission.

The epitaxial growth of carbon nanotubes (CNTs) is an important subject of research. Recent attention has been paid to finding new strategies for the controlled growth of single-wall CNTs with a defined chirality. In addition, many potential applications require multiwall CNTs (MWCNTs) to grow vertically from the substrate and the interface property is crucial. Here, we report for the first time that MWCNTs can grow directly from the surface of a substrate by epitaxy, based on the experimental study of individual multiwall carbon nanotubes on a large-area stainless steel substrate, which is a very useful system for electrical and mechanical applications. In particular, evidence is given of the lattice matching between the MWCNT and the lattice of a hexagonal Cr2O3: (Fe, Mn) film formed on the surface of the substrate. Furthermore, a method is developed to increase the density of the MWCNTs; a mechanism of simultaneous top and bottom growth is proposed. The resultant significantly improved electrical transport and field emission properties are also presented, showing the Ohmic contact for electrical conduction and high performance in resisting the catastrophic cold-cathode vacuum breakdown of the CNTs.

The genetic polymorphisms of beta3-adrenergic receptor (AR) Trp64Arg and beta2-AR Gln27Glu are associated with obesity in Chinese male hypertensive patients.

BACKGROUND: Genetic polymorphisms of beta3-adrenergic receptor (AR) Trp64Arg and beta2-AR Gln27Glu may result in significant change in the functions of these receptors. The aims of the present study were to investigate the association between Trp64Arg, Arg16Gly and Gln27Glu polymorphisms and the susceptibility to obesity and hypertension in a Chinese population. METHODS: A total of 437 Chinese subjects including 149 obese hypertensive patients, 139 non-obese essential hypertensive patients, and 149 non-obese normotensive healthy controls were enrolled in the study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele-specific (AS)-PCR assays were used to identify Trp64Arg, Arg16Gly, and Gln27Glu genotypes. RESULTS: The allele frequencies of 64Arg and 27Glu in the obese hypertensive group were 0.178 and 0.128, respectively. Both were significantly higher than in the non-obese hypertensive and the control groups (p<0.05). Further analysis showed that this association existed only in male hypertensive patients. CONCLUSIONS: These data reveal that frequencies of beta3-AR 64Arg and beta2-AR 27Glu were significantly higher in our obese hypertensive patients than in the non-obese hypertensive population and healthy controls. beta3-AR Trp64Arg and beta2-AR Gln27Glu genetic polymorphisms are associated with obesity in Chinese male hypertensive patients.