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Semi-volatile oxygenated organics and ammonium chloride increasing sub-micron aerosol hygroscopicity, cloud condensation nuclei and PM1 mass in the Delhi region
No full textInsights into structural, thermal, physical, optical, and electrical properties of novel ZnO-doped lithium–titanium-phosphate glasses
No full textThis study investigates novel ZnO-doped lithium-titanium-phosphate glasses, synthesized via the melt-quenching method, and characterizes their physical, structural, thermal, optical, chemical, mechanical, and electrical properties, with a focus on the impact of varying ZnO content on these properties. An increase in ZnO content from 20 mol% to 27.27 mol% induces significant local structural changes, promoting enhanced network polymerization, density, and chemical durability, while concurrently reducing thermal stability and mechanical strength. EPR analysis confirmed that titanium remained in the Ti4+ state, while optical measurements revealed an increased band gap, attributed to the role of ZnO in preventing Ti4+ reduction and minimizing localized states. The electrical conductivity decreases with increasing ZnO content, with the highest value measured at 1.73 × 10-10 Ω-1 cm-1. High-ZnO glasses exhibit mainly electronic conductivity of 4.02 × 10-9 Ω-1 cm-1 at room temperature. The frequency-dependent conductivity follows Jonscher's power law, with the charge transport governed by a correlated barrier-hopping mechanism, remaining stable across temperatures and compositions
Next-generation Li1.3+xAl0.3AsxTi1.7-x(PO4)3 NASICON electrolytes with outstanding ionic conductivity performance
No full textNASICON-type solid electrolytes feature prominently in the improved safety and energy density of solid-state lithium batteries (ASSLBs). Achieving high ionic conductivity in these electrolytes is key to optimizing their performance. In this study, we introduced a new class of NASICON-type materials by doping arsenic into the Li1.3Al0.3Ti1.7(PO4)3 framework, creating a series of Li1.3+xAl0.3AsxTi1.7-x(PO4)3 phases with varying arsenic content (x = 0, 0.1, 0.2, 0.3), synthesized using the standard solid-state reaction method. X-ray diffraction confirmed the successful formation of the Li1.3+xAl0.3AsxTi1.7-x(PO4)3 phases, which was further validated by Rietveld refinement. Structural analyses through FT-IR, Raman spectroscopy, NMR, and ICP-AES studies validate the effective incorporation of arsenic into the lattice. Among the different compositions, Li1.5As0.2Al0.3Ti1.5(PO4)3 phase stood out due to its high relative density of 89% and its pore-free microstructure, as observed through scanning electron microscopy results, revealing the largest grain and crystallite size. Notably, doping with arsenic resulted in a significant enhancement in ionic conductivity, increasing from 5.34×10-5 Ω-1.cm-1 for Li1.3Al0.3Ti1.7(PO4)3 to 8.57×10-4 Ω-1.cm-1 for the Li1.5As0.2Al0.3Ti1.5(PO4)3 at 25°C. With a lithium transference number of 0.99, and a conduction mechanism largely unaffected by changes in temperature or composition, demonstrating its suitability as a promising candidate for solid electrolyte applications
Water modulated influence of intramolecular hydrogen-bonding on the conformational properties of Cannabidiol (CBD)
No full textCannabidiol (CBD), a non-psychoactive phytocannabinoid from Cannabis sativa, has gained significant attention due to its diverse therapeutic properties, including anti-inflammatory, antioxidant, and anxiolytic effects. However, its clinical application is hindered by poor water solubility, which limits its bioavailability. The aim of this study is to deepen our understanding of the conformational properties of CBD, and investigate how these properties affect its solubility. Using Density Functional Theory (DFT) calculations, we analyzed the axial and equatorial positions of substituents on the limonene ring and the arrangement of both hydroxyl groups. Our findings indicate that the most stable conformation of CBD involves diequatorial substitution on the limonene ring, stabilized by specific –OH⋯π hydrogen bonding interactions. All-atom Molecular Dynamics (MD) simulations in an aqueous environment revealed that while single CBD molecules maintain their conformation, multiple CBD molecules tend to cluster. These insights provide a comprehensive understanding of the molecular interactions that underlies CBD’s low aqueous solubility and suggests potential strategies for enhancing its bioavailability, which could optimize its therapeutic potential
High-resolution source apportionment and health risks of PM2.5-bound trace elements across a major Indian city: Seasonal and diurnal insights from a multi-site campaign using a mobile laboratory platform
No full textNovel Mn2+-doped NASICON glass-ceramic electrolyte with engineered columnar microstructure for high lithium-ion conductivity
No full textGlass-ceramic electrolytes are poised to revolutionize energy storage as breakthrough candidates for next-generation all-solid-state lithium batteries. This study introduces a high-performance and new Mn-doped NASICON-type (Li1.2Mn0.1Ti1.9(PO4)3) phase within a glass-ceramic electrolyte, synthesized via a melt-quenching and crystallization protocol. Crystallization analysis reveals a surface-to-bulk phase transformation via a one-dimensional nucleation process, with a low activation energy of 161.68 kJ.mol-1, enabling a Li-enriched NASICON matrix at reduced temperatures. Structural characterization through Rietveld-refined XRD, and 7Li and 31P MAS NMR spectroscopy, verified Mn2+ substitution within the crystal lattice, causing bottleneck size expansion and weakened Li+-O bonding, enhancing ion mobility. FT-IR and Raman spectra further confirm the successful formation of the Li-rich NASICON phase. SEM/TEM imaging revealed a unique columnar grain morphology that reduces grain boundary areas and porosity, while the residual glass phase (11.2%) enhances interfacial Li⁺ transfer. The optimized LMnTP-0GC composition (30Li2O-20TiO2-20MnO-30P2O5) delivered high-ionic conductivity (2.73×10-4 S.cm-1at RT), low electronic leakage (3.425×10-8 S.cm-1), and near-unity Li⁺ transference number (0.9998) outperforming undoped LiTi2(PO4)3 and Mn-enriched counterparts. The Li|LMnTP-0GC|Li cell achieves 2 mA.cm-2 CCD and stable cycling for 200 h, while the Li|LMnTP-0GC|LFP cell delivers 130.00 mAh.g-1 with 96.40% retention after 50 cycles at 0.1C
Novel Zn-doped Nasicon-based glass-ceramic with superior Li-conductivity and enhanced properties as a solid electrolyte
No full textAmong the diverse array of solid electrolyte options, glass-ceramics hold great promise for application in all-solid-state lithium batteries. In this respect, we have effectively developed novel glasses and glass-ceramics through an innovative approach that integrates a glass-ceramic strategy with the newly introduced zinc-doped Nasicon phase. This was achieved by applying melt-quenching techniques coupled with meticulous control over the crystallization process, guided by a thorough study of crystallization kinetics. The crystallization kinetics have unveiled a two-dimensional nucleation mechanism with an activation energy of 165 kJ.mol-1. X-ray diffraction (XRD) analysis revealed the emergence of a novel Zn-doped Nasicon phase, identified as Li1.6Zn0.3Ti1.7(PO4)3, within the 30Li2O-20ZnO-20TiO2-30P2O5 glass-ceramic, a validation corroborated through Rietveld refinement. Indeed, FT-IR, Raman, and NMR analyses confirmed the formation of Li1+2xZnxTi2-x(PO4)3 Nasicon phase within the glass-ceramics structures. Moreover, SEM images, complemented by TEM observations and density assessments, provide evidence for the creation of a dense, pore-free glass-ceramic with a striped microstructure. The 30Li2O-20ZnO-20TiO2-30P2O5 glass-ceramic demonstrates outstanding chemical durability and robust mechanical properties. Notably, it exhibits high total ionic conductivity, reaching 7.14.10-4 Ω-1.cm-1 at room temperature, while displaying low electronic conductivity of 8.10-9 Ω-1.cm-1, aligning with findings from UV-visible spectroscopy. Additionally, the lithium transference number is confirmed to be 0.99, positioning the developed glass-ceramic as a highly competitive solid electrolyte in the field of energy storage. DFT calculations were conducted on the crystallized Li1.6Zn0.3Ti1.7(PO4)3 NASICON phase to gain detailed insights into its thermodynamic stability and electronic properties
Enhanced stability and high rate capability of garnet solid-state electrolyte interface through integration of nanoscale Li4Ti5O12 for Li battery applications
No full textGarnet-type solid-state electrolytes (SSE) have garnered considerable interest because of their high ionic conductivity and broad electrochemical window. However, poor interfacial contact with lithium metal remains a persistent challenge, leading to insufficient interfacial stability and low rate performances of the SSE. In this study, the surface of the garnet LLZTO (Li6.45Al0.05La3Zr1.6Ta0.4O12) SSE pellet is integrated with a nanoscale Li4Ti5O12 (LTO) through application of TiO2 using atomic layer deposition (ALD). The 2.5 nm TiO2 layer reacts with Li2CO3 on the surface and grain boundaries of LLZTO pellet to form the nanoscale Li4Ti5O12 (LTO) during the sintering process. The integrated nanoscale LTO enhances the wettability of LLZTO SSE with lithium metal and reduces the grain boundary resistance, providing a stable and zero-strain channel for lithium deposition and stripping. These features promote uniform lithium deposition and rapid lithium ion migration through LLZTO, thereby suppressing lithium dendrite formation and achieving high rate performance. These findings offer new insights into the surface modification strategies for garnet-type SSE aimed at improving their wettability, interfacial stability, and rate capability in lithium battery
