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Metal-free photocatalysis that produces reactive oxygen species (ROS) shows significant promising applications for environmental remediation. Herein, we constructed iodine-doped carbon nitride (I-CN) for applications in the photocatalytic inactivation of bacteria and the heterogeneous Fenton reaction. Our findings revealed that I-CN demonstrates superior photocatalytic activity compared to pure CN, due to enhanced light adsorption and a narrowed band gap. Antibacterial tests confirmed that I-CN exhibits exceptional antibacterial activity against both Escherichia coli and Staphylococcus aureus. The results showed that I-CN effectively generates superoxide radicals and hydroxyl radicals under light irradiation, resulting in enhanced antibacterial activity. In addition, I-CN can also be applied for a heterogeneous photo-Fenton-like reaction, achieving a high performance for the degradation of sulfamethoxazole (SMX), a typical antibiotic, via the photocatalytic activation of peroxymonosulfate (PMS). These results shed new light on the fabrication of metal-free nanozymes and their applications for disinfection and water decontamination. [ABSTRACT FROM AUTHOR]

The Li21Si5 alloy is a promising pre-lithiation material for lithium-ion batteries (LIBs). However, its instability in atmospheric environments and polar solutions limits its applications, particularly in the field of water-based anodes. Herein, a PEO-Li21Si5 coating strategy was proposed to efficiently replenish lithium and stabilize the electrode structure for LIBs. Polyethylene oxide (PEO) was added to Li21Si5 to create a PEO-Li21Si5 pre-lithiation layer, which was coated on the surface of the Si@C anode. HRTEM and XPS tests indicated that the PEO (weakly polar) would react with the interface of the Li21Si5 to build a stable passivation layer, allowing lithium ions inside the Li21Si5 to be released during the first cycle, which in turn improved the ICE of the LIBs. Moreover, PEO-Li21Si5 was able to coat the Si@C particles due to the wettability of the electrolyte to PEO. And it would suppress the displacement caused by the cyclic expansion of the Si, achieving the stability of the electrode structure. This strategy achieved an initial coulombic efficiency (ICE) of over 100% with stable and long-lasting cycles. [ABSTRACT FROM AUTHOR]

The (electro)chemical reactions between Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid‐state electrolyte and lithium metal plague the practical applications of LATP. A commonly used strategy to tackle this issue is to construct an ionic conductor layer to stabilize Li/LATP interface. Herein, it is demonstrated that an electronic conductor interlayer (Al or Ag) can also greatly enhance the interfacial stability of Li/LATP. To unveil the origin of the enhanced interfacial stability, a series of techniques, including in situ electron and optical microscopies, kelvin probe force microscopy, and finite element analysis, is exploited. Control experiments show clearly that Al layer can effectively homogenize the electric field distribution, which enables the uniform growth of interphases and thus prevents stress concentration and crack propagation. Moreover, when coupled with solid polymer electrolyte (SPE) to form Al‐SPE bilayer, it can effectively protect LATP from electron attack and interphase formation. Remarkably, Li symmetrical cells with an Al‐SPE bilayer exhibit superior stability of more than 5000 h at 0.2 mA cm−2, among the best cycling performances to date. This work presents an in‐depth understanding of the mechanism of the enhanced interfacial stability enabled by electronic conductor interlayers, as well as a universal interface architecture to boost the cyclability of solid‐state batteries. [ABSTRACT FROM AUTHOR]

To address the issues of the particle fracture and loss of electrical connectivity of high capacity silicon anodes, herein, we propose a novel strategy that combines surface carbon coating and bulk boron doping. Heavily boron doped polycrystalline photovoltaic Si particles are used as starting materials. The bulk boron doping is demonstrated to enhance both electron transportation and lithium-ion diffusion, which contributes to superior high-rate performance. Taking advantage of the fast kinetics and stable interphase with the electrolyte, the carbon coated boron doped Si electrode exhibits higher capacity retention. For example, the capacity retentions are 668 mA h g−1, 293 mA h g−1 and 79 mA h g−1 at a high rate of 0.5C (1C = 4000 mA g−1) after 500 cycles for 3900 ppm, 120 ppm, and 10 ppm boron doped Si, respectively. In addition, an improved mass loading of 2.0 mg cm−2, high areal capacity (3.9 mA h cm−2) and high-volume capacity (2111 mA h cm−3) are achieved. Our work opens a new horizon for designing stable high loading Si anodes, which is applicable for other alloy electrode materials. [ABSTRACT FROM AUTHOR]

Hydride-Powder-Sintering(HPS) as a new preparation approach was applied in the low cost V 40 Ti 26 Cr 26 Fe 8 hydrogen storage alloys successfully, which provides an alternative preparation route for other types of hydrogen storage alloys. V 40 Ti 26 Cr 26 Fe 8 alloy exhibits ideal hydrogen absorption-desorption performance after adding moderate content of LaH 3. Optimizing sintering process by increasing the sintering temperature and time has improved hydrogen desorption plateau evidently. X-ray diffraction analysis results show that the Ti-Oxide phase basically no longer exists when the LaH 3 content is greater than or equal to 3 wt% as compared to that of LaH 3 content below 3 wt%. Pressure-Compose-Temperature(PCT) curves show that the hydrogen absorption and desorption capacities increase gradually with the increase of LaH 3 content. The lattice parameters calculated by Rietveld refinement has the same variety rule as the hydrogen absorption-desorption capacities with the increase of LaH 3 content. It can be inferred that the addition of LaH 3 has reduced the content of Ti-Oxide and then the lattice parameters increase, which leads to the improvement of hydrogen performance of the alloy. The most appropriate preparation process is 3 wt% of LaH 3 additive with a sintering process 1673 K-6h, correspondingly, the hydrogen absorption and desorption capacities are 3.13 wt% and 1.97 wt%, respectively. • Hydride-Powder-Sintering(HPS) was applied in the V-based alloy successfully. • LaH 3 significantly improved the hydrogen storage performances of V 40 Ti 26 Cr 26 Fe 8. • Hydrogen desorption plateau was improved effectively by HPS process optimization. • HPS can be extended to be applied in other types of hydrogen storage alloys. [ABSTRACT FROM AUTHOR]

Baicalin is a traditional Chinese herb purified from the root of Scutellaria baicalensis Georgi. In this study, we further analyzed the molecular mechanism behind the anti-tumor activity of Baicalin in colorectal cancer (CRC). The establishment of circular RNA (circRNA)/microRNA (miRNA)/messenger RNA (mRNA) axis was predicted by bioinformatic databases and verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Baicalin dose-dependently reduced the expression of circRNA myosin heavy chain 9 (circMYH9) in CRC cells. Baicalin exposure suppressed the malignant phenotypes of CRC cells, which were largely reversed by the overexpression of circMYH9. CircMYH9 functioned as a molecular sponge for miR-761. CircMYH9 overexpression protected CRC cells from Baicalin-induced injury partly through down-regulating miR-761. MiR-761 interacted with the 3′ untranslated region (3' UTR) of hepatoma-derived growth factor (HDGF) mRNA. CircMYH9 up-regulated HDGF expression partly through sponging miR-761 in CRC cells. MiR-761 silencing counteracted the anti-tumor activity of Baicalin partly through up-regulating HDGF in CRC cells. Baicalin suppresses xenograft tumor growth in vivo , and this suppressive effect was partly reversed by the overexpression of circMYH9. In conclusion, Baicalin exhibited an anti-tumor activity in CRC cells partly through down-regulating circMYH9 and HDGF and up-regulating miR-761. • Baicalin exposure down-regulates circMYH9 expression in a dose-dependent manner. • CircMYH9 overexpression largely overturns the anti-tumor role of Baicalin in CRC cells. • CircMYH9 acts as miR-761 sponge in CRC cells. • HDGF is a target of miR-761 in CRC cells. • Baicalin suppresses the malignant behaviors of CRC cells partly through regulating circMYH9/miR-761/HDGF signaling. [ABSTRACT FROM AUTHOR]

The V-Ti-based hydrogen storage alloy (FeV80) 48 Ti 26 Cr 26 was synthesized by the hydride powder sintering method. X-ray diffraction (XRD) analysis results show that the alloy consists of a main BCC phase, a La 2 O 3 phase and a Ti-rich oxide phase. The existence of the Ti-rich oxide phase leads to a loss of Ti element content in the main BCC phase and further results in a lattice contraction. Thus, the hydrogen absorption capacity of the alloy synthesized by the hydride powder sintering method is only 2.8 wt%, with a hydrogen desorption capacity of 1.5 wt%. To address this problem, the effects of Ti element compensation on the microstructure and the hydrogen storage capacities of the alloy were investigated. It was found that the lattice constant of the BCC phase increases and the amount of Ti-rich oxide phase is almost unchanged with increased Ti element compensation, leading to an improved hydrogen storage capacity. When Ti element compensation reaches 4 at%, the hydrogen absorption capacity of the alloy reaches 3.3 wt% with a desorption capacity of 2.0 wt% at room temperature and at a pressure of 10 −4 MPa. The hydrogen desorption plateau slope factor of the (FeV80) 48 Ti 26+x Cr 26 (x = 0–4) alloy prepared by the hydride powder sintering method is as small as that of the alloy prepared by the arc-melting method. Thus the sintering method is a suitable option for the manufacture of V-Ti-based hydrogen storage alloys. [ABSTRACT FROM AUTHOR]

The LaNi 3.8 -type LaNi 3.8 and La 0.8 Mg 0.2 Ni 3.8 hydrogen storage alloys were prepared by high frequency induction melting (HFIM) under helium atmosphere followed by annealing treatment. Either alloy mainly consists of a rhombohedral Ce 5 Co 19 -type phase (R-3 m) and a hexagonal Pr 5 Co 19 -type (P6 3 /mmc) phase. The unit cell volume of either Ce 5 Co 19 -type or Pr 5 Co 19 -type phase in the La 0.8 Mg 0.2 Ni 3.8 alloy is smaller than that in LaNi 3.8 . The Mg-containing La 0.8 Mg 0.2 Ni 3.8 alloy has a lower absorption/desorption plateau, smaller hysteresis and a higher hydrogen storage capacity than those of LaNi 3.8 . The La 0.8 Mg 0.2 Ni 3.8 alloy electrode shows an excellent activation capability and a higher discharge capacity (373.1 mA h g −1 ) than those of the LaNi 3.8 alloy electrode (184.0 mA h g −1 ). The capacity decay rate of the La 0.8 Mg 0.2 Ni 3.8 alloy electrode (0.88 mA h (g cycle) − 1 ) is much lower than that of the LaNi 3.8 alloy electrode (1.32 mA h (g cycle) − 1 ), which is attributed to that the addition of Mg suppresses the hydrogen-induced amorphization of the LaNi 3.8 alloy. Moreover, during the charge–discharge cycling of the Mg-containing alloy electrode, the dissolutions of La and Ni in the alkaline solution can be suppressed remarkably due to the sacrifice of Mg, which correspondingly results in preferable cycling stability and an anti-corrosion capability of the La 0.8 Mg 0.2 Ni 3.8 alloy electrode. [ABSTRACT FROM AUTHOR]

In this work, NH3BH3 (AB) is used to induce hydrogen generation during NaBH4 (SB) hydrolysis in order to reduce the use of catalysts, simplify the preparation process, reduce the cost and improve desorption kinetics and hydrogen capacity as well. xNaBH4–yNH3BH3 composites are prepared by ball-milling in different proportions (from x:y = 1:1 to 8:1). The experimental results demonstrate that all composites can release more than 90% of hydrogen at 70 °C within 1 h, and their hydrogen yields can reach 9 wt% (taking reacted water into account). Among them, the composites in the proportion of 4:1 and 5:1, whose hydrogen yields reach no less than 10 wt%, show the best hydrogen generation properties. This is due to the impact of the following aspects: AB additive improves the dispersibility of SB particles, makes the composite more porous, hampers the generated metaborate from adhering to the surface of SB, and decreases the pH value of the composite during hydrolysis. The main solid byproduct of this hydrolysis system is NaBO2·2H2O. By hydrolytic kinetic simulation of the composites, the fitted activation energies of the complexes are between 37.2 and 45.6 kJ mol−1, which are comparable to the catalytic system with some precious metals and alloys. [ABSTRACT FROM AUTHOR]