Publications by authors named "R Vivani"
Article Synopsis
- Layered double hydroxides (LDHs) are versatile materials, and this study focuses on improving their synthesis methods to control composition and morphology effectively.
- The researchers modified the traditional urea method to produce MgAl and ZnAl LDHs in chloride and nitrate forms through a single-step process, optimizing factors like molar ratio, reaction time, and metal salt concentration.
- Results showed that varying the molar ratio and metal salts influenced the morphology, leading to different crystal shapes, such as sand-rose and plate-like crystals, while a detailed analysis of the growth mechanisms was also provided.
Article Synopsis
- Lead-calcium phosphates, specifically the (PbCa)(PO)OH solid solution, are valuable materials found in cultural heritage artifacts, yet their diagnostic properties have been under-studied.
- This paper investigates the relationship between the composition and structure of these compounds, aiming to establish key markers for their identification in cultural heritage samples using non-destructive methods.
- The researchers used advanced techniques like scanning electron microscopy and synchrotron radiation-based X-ray methods to analyze variations in these materials, providing useful data and methods for future studies in the field.
Article Synopsis
- Recent advancements in electrocatalytic oxygen evolution reaction (OER) show that earth-abundant catalysts still lack optimal efficiency due to complexities in the catalytic system.
- The study focuses on the impact of the tunable 3D configuration of metal centers, specifically in one-dimensional coordination polymers made of metals like Fe, Co, and Ni, which helps clarify their catalytic performance.
- Findings reveal that electronic structure, including metal spin and oxidation state, significantly affect ligand binding and can potentially reduce overpotential in OER, aiding in the design of more effective catalysts.
Non-invasive detection of lead carboxylates in oil paintings by in situ infrared spectroscopy: How far can we go?
Spectrochim Acta A Mol Biomol Spectrosc
November 2023
This paper demonstrates the efficacy of portable mid-infrared spectroscopy as a diagnostic tool for revealing the presence of lead carboxylates on artworks, in situ, without sampling. Samples of cerussite and hydrocerussite - the main components of lead white - were separately mixed with linseed oil, and artificially aged in two steps. Their compositional changes have been monitored over time by infrared spectroscopy in two investigation modes: absorption (benchtop instrument) and reflection (portable instrument), and by XRD spectroscopy.
View Article and Find Full Text PDFAnhydrous Superprotonic Conductivity in the Zirconium Acid Triphosphate ZrH (PO ).
Angew Chem Int Ed Engl
April 2023
The development of solid-state proton conductors with high proton conductivity at low temperatures is crucial for the implementation of hydrogen-based technologies for portable and automotive applications. Here, we report on the discovery of a new crystalline metal acid triphosphate, ZrH (PO ) (ZP3), which exhibits record-high proton conductivity of 0.5-3.
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