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Effect of deposit composition and thermal cycling parameters on oxide- and sulfate-induced hot corrosion of CoNiCrAlY HVOF coatings
No full textTailoring NiFeS microstructure through electrodeposition for high-performance anion exchange membrane water electrolysis
No full textRevealing the in-situ growth mechanism of carbon dots confined in ZIF-8 as multicolor fluorescent material with high photothermal stability
No full textCarbon dots (CDs) based fluorescent materials offer tremendous potential for application in high-definition displays and advanced illumination systems. However, achieving solid-state CDs-based phosphors with robust photothermal stability remains a critical challenge. In this study, multicolor CDs@ZIF-8 phosphors were synthesized by precisely controlling the carbonation degree of CDs under the confinement effect of ZIF-8. Serving as both template and a protective substrate, ZIF-8 enables the in-situ carbonation of the carbon source into CDs embedded within its pores through a solvothermal process. Structural and compositional analyses following HCl etching of the multicolor CDs@ZIF-8 phosphors showed that the in-situ growth of CDs in ZIF-8 pores. The multicolor emission of the CDs is attributed to the quantum size effect. The rigid structure of the ZIF-8 backbone imparts exceptional photothermal stability to the CDs@ZIF-8 phosphors. As a result, the materials exhibit stable fluorescence under continuous laser diode (LD) irradiation for up to 60 min and zero quenching at temperatures as high as 205 °C. These properties are further validated in LD illumination applications. This work provides a novel strategy for the development of high-performance CDs-based phosphors with excellent photothermal stability and offers significant insights into the integration of CDs with porous materials. The findings hold considerable promise for advancing the design and utilization of CDs in solid-state lighting and display technologies
NASICON As-doped and glass additive dual strategy for novel NASICON-glass composite with superior ionic conductivity
No full textDue to their desirable properties, NASICON-type LATP materials are considered strong candidates for use as solid-state electrolytes in lithium batteries. However, their ionic conductivity, essential for optimal battery performance, remains lower than liquid electrolytes. This study highlights the effectiveness of a dual-strategy approach to improve LATP NASICON materials' ionic conductivity. By substituting titanium with arsenic, we developed a high-ion-conducting phase, Li1.5Al0.3As0.2Ti1.5(PO4)3, which showed significant advancements, achieving a high relative density of 89% and an average grain size of 51 nm, which contributes to its improved performance. These modifications led to a significant boost in the ionic conductivity of the arsenic-doped LATP phase, which rose from 5.34 × 10-5 S.cm-1 for LATP to 8.57 × 10-4 S.cm-1 for the Li1.5Al0.3As0.2Ti1.5(PO4)3 phase at room temperature with an activation energy of 0.30 eV and a transference number close to 1. To address remaining porosity and grain boundary resistance, we developed a novel glass-ceramic composition by incorporating a high-ion-conducting glass additive (45Li2O-10Li2WO4-45P2O5) into the new elaborated Li1.5Al0.3As0.2Ti1.5(PO4)3 matrix. The addition of 3 wt.% glass content notably enhanced the density and compactness of the material, increasing its ionic conductivity to 4.6 × 10-3 S. cm-1 at 25 °C with an activation energy of 0.25 eV, representing the highest ionic conductivity reported for NASICON and NASICON-composite materials. This work provides a cost-effective and efficient method for producing novel NASICON ceramics and glass-ceramic composites with superior ionic conductivity, setting a new benchmark for NASICON-composite materials and advancing the development of high-performance solid-state electrolytes for lithium batteries
