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A high-performance K-NH 4 V 4 O 10 (K-NVO) cathode with K+ doping was synthesized successfully through one-step hydrothermal method, which exhibits lower barriers for Zn2+ diffusion and superior stability, leading to excellent electrochemical performance. [Display omitted] Aqueous zinc-ion batteries (AZIBs), defined by low expenses, superior safety, and plentiful reserves, demonstrate tremendous development potential in energy storage systems at the grid scale. Whereas the cathode instability and the limited diffusion of Zn2+ have impeded the development of AZIBs. Herein, a high-performance K-NH 4 V 4 O 10 (K-NVO) cathode with K+ doping synthesized successfully through one-step hydrothermal approach. Experiments and density functional theory (DFT) calculations indicate that K-NVO has Zn2+ diffusion pathways with lower barriers for smoother transport, and lower formation energy. The combination of the rapid Zn2+ diffusion and the stable structure results in outstanding electrochemical performance of K-NVO as demonstrated in tests. K-NVO cathode achieves a specific capacity of 406 mAh g−1 at 0.2 A g−1, maintains satisfactory cyclic stability with 81.6 % capacity retention after 1000 cycles at 5 A g−1, and possesses a high energy density of 350.9 Wh kg−1. Furthermore, confirmation of the zinc storage mechanism in K-NVO was carried out through Ex situ tests, such as XRD and XPS. This research contributes a unique perspective to the formulation of high-performance cathode materials for AZIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Given their plentiful reserves, impressive safety features, and economical pricing, aqueous zinc − ion batteries (ZIBs) have positioned themselves as strong competitors to lithium − ion batteries. Yet, the scarcity of available cathode materials poses a challenge to their continued development. In this study, a V 2 O 5 /V 6 O 13 heterostructure has been synthesized using a one − pot hydrothermal approach and employed as the cathode material for ZIBs. As evidenced by both experimental and theoretical findings, V 2 O 5 /V 6 O 13 heterostructure delivers a rapid electrons and ions diffusion kinetics promoted by the stable interface and strong electronic coupling with significant charge transfer between V 2 O 5 and V 6 O 13 , as well as a stable interface achieved by adjusting V − O bond length. Consequently, the optimized V 2 O 5 /V 6 O 13 heterostructure cathode of ZIBs demonstrates exceptional capacity (338 mAh g−1 at 0.1 A g−1), remarkable cycling stability (92.96 % retained after 1400 cycles at 1 A g−1). Through comprehensive theoretical calculations and ex situ characterization, the kinetic analysis and storage mechanism of Zn2+ are thoroughly investigated, providing a solid theoretical foundation for the advancement of novel V − based cathode materials aimed at enhancing the performance of ZIBs. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The detection of water soluble vitamins using electrochemical method is widely established in pharmaceutical quality control laboratories, and especially the recent advances in hybrid heterostrucure nanomaterials has devoted to enhance the significant analytical parameters like sensitivity, selectivity and fast response time. Herein, we report the synthesis of a hybrid heterostructure comprising SnO 2 nanoparticles supported mesoporous TiO 2 , and the obtained nanocomposite were fabricated over glassy carbon electrode (GCE) for the electrochemical oxidation of vitamin B 6 in pharmaceutical tablets. The designed SnO 2 -TiO 2 /GC modified electrode exhibits well-defined oxidation peak with lowering over-potential and larger signal response compared to the pristine counterparts, and it is mainly due to the formation of abundant active surface layer offered by SnO 2 cocatalyst, and thus significantly enhances the electrochemical surface area. Differential pulse voltammetry (DPV) measurements revealed a sharp increase in the anodic peak current upon addition of increasing concentration of vitamin B 6. The analytical performance of the modified electrode displayed a wide linear range (0.1–31.4 µM), high selectivity, and excellent sensitivity (759.73 µA mM−1 cm−2) with low detection limit (35 nM). Thus, the resultant mesoporous hybrid nanocatalyst provides an efficient electrochemical platform for determination of various potential analytes. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO 2 ) has been widely investigated as a photocatalyst material because of its stability and hypotoxicity. However, the photocatalytic activity of TiO 2 is suppressed by the large band gap and the high recombination rate of the charge carrier, which leads to confined application. Moreover, how to improve photocatalytic H 2 production without any co-catalyst remains a big challenge. Here, we report a conceptual strategy in a core–shell nanostructure of simultaneously reducing the band gap and the charge carrier recombination rate by introducing a carbon-doped porous TiO 2 layer onto a metallic TiC nanostructure using a facile in situ thermal growth method. TiC@C-TiO 2 core–shell nanostructure materials have higher photocatalytic activity in methanol aqueous solution than those of pure P25 and carbon-doped TiO 2 , which results from enhanced visible light absorption, drastic charge transfer, and the large surface area. Notably, the novel core–shell nanostructures still exhibit excellent photocatalytic H 2 production without Pt co-catalyst. The results demonstrate that TiC is an ideal support for TiO 2 photocatalysts, and this novel core–shell nanostructure can significantly shift the position of the band edge of the obtained material. This study presents a design principle for photocatalytic materials as highly efficient visible light photocatalysts. [ABSTRACT FROM AUTHOR]

Pharmaceuticals, personal care items, steroid hormones, and agrochemicals are among the synthetic and indigenous products that make up micropollutants, also known as emerging contaminants. Pharmaceutical and personal care products (PPPs) are a class of developing micropollutants that can harm living organisms even at low concentrations. Many are detected in surface water and wastewater from the treatment process, with quantities ranging from ng L-1 to gL-1; however, residual PPPs at dangerously high levels have indeed recently been recognized in the ecosystem. Residential sewage treatment plant (STP) dump the largest majority of these pollutants into the environment on a regular basis. As a result of its robust structure, it has a longer lifespan in the environment. This review article discusses how surface water pollutants such pesticides, petroleum hydrocarbons, and perfluorinated compounds affect water quality, as well as the most cost-effective adsorbents for removing these PPPs. The goal of this study is to provide information about the origins of PPP, as well as diagnostic procedures and treatment options. Research on developing contaminants is also aimed at evaluating the efficacy and affordability of adsorption. • The methods for identifying pharmaceutical and personal care goods in aquatic systems are evaluated critically. • Adsorption and Advance oxidation process show great potential for treatment of PPPs. • PPPs were degraded using a variety of treatment approaches. • The effects of PPPs in the environment on human health were assessed. • Suggestions were made for further study. [ABSTRACT FROM AUTHOR]

Abstract: The coordination and structure changes in LiBO2 have been studied at high pressure and temperature up to 5GPa and 1500°C using in-situ high-pressure differential thermal analysis, infrared absorption spectra and X-ray diffraction. The layer framework structure of α-LiBO2 is found to be compressed easily along the direction of c-axis, resulting in the formation of tetra-coordinated BO4 units. The phase transition boundaries between α- and γ-LiBO2 as well as between amorphous LiBO2 hydrate and γ-LiBO2 have negative pressure–temperature slopes. The conditions for transformation from α- to γ-LiBO2 are lower than that necessary to transform amorphous LiBO2 hydrate to γ-LiBO2. Moreover, the melting curve of LiBO2 has also been determined and has a positive pressure–temperature slope. Upon quenching from high pressure, LiBO2 may not contain [3]B–O–[3]B rings but contain more fraction of [4]B units with increasing pressure. [Copyright &y& Elsevier]