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Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Two-dimensional correlation infrared spectroscopy study on vanadoborate anionic skeleton regulated by countercations
Ming-Ze Meng1, Gui-Dong Shi1, Ling-Ling Cheng1
1College of Chemistry, Fuzhou University, Fuzhou 350002, Fujian, China.
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|February 8, 2024
Summary
Two novel vanadoborate compounds were synthesized, revealing that different countercations alter their anionic skeletons and V4+/V5+ ratios. This impacts their aromaticity, magnetic responses, and electrocatalytic activity, particularly in compound 2.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Computational Chemistry
Background:
- Vanadoborate compounds are of interest due to their diverse structures and potential applications.
- Understanding how structural modifications, such as variations in countercations, affect material properties is crucial.
- The relationship between electronic structure, magnetic properties, and catalytic activity in these materials requires further investigation.
Purpose of the Study:
- To synthesize and characterize two novel vanadoborate compounds with distinct countercations.
- To investigate the influence of countercations on the vanadoborate cluster anion skeleton and valence states.
- To explore the resulting differences in aromaticity, magnetic response, and electrocatalytic activity using computational and spectroscopic methods.
Main Methods:
- Hydrothermal synthesis was employed to prepare two vanadoborate compounds under varying temperatures.
- Structural analysis was performed to determine the composition and arrangement of the cluster anions and countercations.
- Quantum chemical calculations and two-dimensional correlation infrared spectroscopy (2D-COS-IR) under magnetic perturbation were used to assess aromaticity and magnetic responses.
- Electrochemical analysis was conducted to evaluate the electrocatalytic activity of the synthesized compounds.
Main Results:
- Two novel vanadoborate compounds, [Cu(en)2]3[Li(H2O)]4[Li(H2O)3]2[V12B18O50(OH)10(H2O)]2·33.5H2O (1) and (H2en)4[Li(H2O)]4[V12B18O55(OH)5(H2O)]·14H2O (2), were successfully synthesized.
- Structural analysis revealed variations in the [V12B18O60]n- cluster anion skeletons and V4+/V5+ ratios (10:2 in compound 1, 11:1 in compound 2) due to different countercations.
- Quantum chemical calculations indicated different aromaticity and activity, corroborated by 2D-COS-IR showing distinct functional group vibration responses to magnetic fields.
- Compound 2 exhibited higher electrocatalytic activity compared to compound 1.
Conclusions:
- Countercations play a significant role in dictating the structural integrity and valence states of vanadoborate cluster anions.
- The observed differences in V4+/V5+ ratios and aromaticity directly correlate with variations in magnetic responses and electrocatalytic performance.
- Combining quantum chemical calculations with 2D-COS-IR provides a powerful strategy for understanding structure-property relationships in vanadoborates and designing new materials.
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