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Updated: Jun 23, 2026
07:24
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Structurally Encoded Mixed Proton-Electron Transport in Tetrathiafulvalene-Based Lanthanide MOFs.
Fabio Manna1,2,3, Zhentao Yang4, Mariangela Oggianu1,3
1Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, Monserrato I-09042, Italy.
Journal of the American Chemical Society
|June 22, 2026
Summary
New metal-organic frameworks (MOFs) based on tetrathiafulvalene tetracarboxylate (TTFTC) and lanthanides enable robust mixed proton-electron conduction. These materials exhibit stable semiconducting and proton transport properties across varying humidity levels.
Area of Science:
- Materials Science
- Nanotechnology
- Solid-State Chemistry
Background:
- Metal-organic frameworks (MOFs) offer tunable platforms for advanced material properties.
- Mixed proton-electron conduction is crucial for next-generation electronic devices.
- Tetrathiafulvalene tetracarboxylate (TTFTC) units are known for their electronic properties.
Purpose of the Study:
- To develop robust 2D MOFs for simultaneous proton and electron transport.
- To investigate the influence of lanthanide ions on conduction mechanisms.
- To characterize the stability of conduction pathways under varying humidity.
Main Methods:
- Synthesis of TTFTC-based lanthanide MOFs (Ln = Dy, Er, Yb).
- Single-crystal conductivity measurements (4-probe) for electronic transport.
- Proton conductivity measurements under controlled humidity and temperature.
- Analysis of charge distribution and hydrogen-bonding networks.
Main Results:
- Developed a family of 2D MOFs exhibiting stable mixed proton-electron conduction.
- Narrow-band semiconducting behavior observed due to π-stacked TTFTC columns.
- Efficient proton conduction facilitated by hydrogen-bond networks within Ln6 clusters.
- Er6TTFTC5 showed record conductivity (1.0 × 10-2 S cm-1 electronic, 3.7 × 10-3 S cm-1 proton at 80% RH, 80 °C).
- High ambipolar conductivity values achieved across the lanthanide series.
Conclusions:
- The reported MOFs provide a robust platform for mixed proton-electron conduction.
- Conduction pathways remain stable over a wide range of humidity conditions.
- Framework rigidity and lanthanide choice subtly modulate transport properties.
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