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Photodeposition of Pd onto Colloidal Au Nanorods by Surface Plasmon Excitation
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Putting the Squeeze on Lead Chromate Nanorods
Hongsheng Yuan1, Placida Rodriguez-Hernandez2, Alfonso Muñoz2
1Center for High Pressure Science and Technology Advanced Research (HPSTAR) , 1690 Cailun Road, BLDG 6 , Pudong, Shanghai 201203 , P.R. China.
The Journal of Physical Chemistry Letters
|August 6, 2019
Summary
High-pressure studies reveal PbCrO4 nanorods undergo a unique phase transition, leading to metallization not seen in bulk material. Nanoengineering may enable compression-driven metallization.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Lead chromate (PbCrO4) exhibits specific structural properties under pressure.
- Understanding high-pressure behavior is crucial for materials design.
Purpose of the Study:
- Investigate the high-pressure structural behavior of PbCrO4 nanorods.
- Discover and characterize novel high-pressure phases and transitions.
- Explore the potential for nanoengineering to induce metallization.
Main Methods:
- X-ray diffraction and Raman spectroscopy were employed to study PbCrO4 nanorods.
- Ab initio calculations were used to support experimental findings.
- Analysis of structural, vibrational, and electronic properties was performed.
Main Results:
- A distinct structural sequence was observed in PbCrO4 nanorods, differing from bulk.
- A phase transition to a novel monoclinic AgMnO4-type polymorph occurred at 8.5 GPa.
- Metallization was induced at 44.2 GPa due to band gap collapse, a phenomenon absent in bulk PbCrO4.
Conclusions:
- PbCrO4 nanorods exhibit unique high-pressure behavior compared to bulk.
- A novel high-pressure phase and metallization pathway were discovered.
- Nanoengineering offers a viable strategy for achieving metallization under compression.
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