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Updated: Jul 24, 2025
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Heteropolyacids: An Ultrasensitive Ionic Volume-Enhanced Raman Scattering Platform
Chenying He1,2, Yuanao Zhang1,3, Ting Wen4
1Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China.
Analytical Chemistry
|July 5, 2023
Summary
A novel oxygen vacancy heteropolyacid, H10Fe3Mo21O51 (HFMO), acts as a high-performance platform for volume-enhanced Raman scattering (VERS). This water-soluble material achieves high sensitivity and selectivity for detecting molecules with imino groups.
Area of Science:
- Materials Science
- Analytical Chemistry
- Spectroscopy
Background:
- Surface-enhanced Raman scattering (SERS) is a powerful chemical identification tool.
- Current SERS substrates suffer from low molecular utilization efficiency and selectivity.
- There is a need for advanced materials for enhanced Raman scattering applications.
Purpose of the Study:
- To develop a novel, high-performance volume-enhanced Raman scattering (VERS)-active platform.
- To overcome the limitations of existing SERS substrates.
- To investigate the potential of oxygen vacancy heteropolyacids in VERS.
Main Methods:
- Synthesis of H10Fe3Mo21O51 (HFMO) as a VERS-active platform.
- Investigation of HFMO's water solubility and coordination bonding with probe molecules.
- Characterization of VERS enhancement factor and detection limits using rhodamine 6G and methyl blue.
- Analysis of selectivity using X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations.
Main Results:
- HFMO demonstrated a high enhancement factor of 1.26 × 10^9 and a detection limit of 10^-13 M for rhodamine 6G.
- A robust O-N coordination bond and a Mo-O-N electron transfer path led to high selectivity for molecules with imino groups (e.g., methyl blue, detection limit: 10^-11 M).
- The HFMO platform exhibited excellent reproducibility, uniformity, high-temperature resistance, and stability under laser irradiation and acidic conditions.
Conclusions:
- HFMO serves as a highly effective, water-soluble VERS platform with noble metal-comparable performance.
- The unique coordination and electron transfer mechanisms provide high selectivity for specific molecular structures.
- This ionic type VERS platform opens avenues for developing highly sensitive, selective, and water-soluble VERS technologies.
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