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Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
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Tunable Work Functions in Plasmonic Metals
Kanij Mehtanin Khabir1, Leila Hesami1, Anthony P Martin2
1Center for Materials Research, Norfolk State University, Norfolk, VA 23504, USA.
Nanomaterials (Basel, Switzerland)
|October 15, 2025
Summary
The deposition of BITh molecules reduces the work functions of silver and gold films. Quartz lamp illumination further decreases work functions, with effects reversible upon light removal, indicating independence from photopolymerization.
Area of Science:
- Surface Science
- Materials Science
- Photophysics
Background:
- Work function modification is crucial for tuning electronic properties of metal surfaces.
- Organic molecules can alter metal work functions, impacting device performance.
- Light-matter interactions offer pathways for dynamic control of material properties.
Purpose of the Study:
- To investigate the impact of BITh molecules on the work functions of silver (Ag) and gold (Au) substrates.
- To explore the influence of quartz lamp illumination on BITh-coated Ag and Au films.
- To differentiate light-induced work function changes from photopolymerization.
Main Methods:
- Fabrication of silver and gold films coated with BITh molecules.
- Utilized reflection and Kelvin Probe experiments to measure work functions.
- Investigated work function changes under quartz lamp illumination and in darkness.
Main Results:
- Deposition of BITh molecules significantly reduced the work functions of both Ag and Au.
- Quartz lamp illumination caused reversible work function reductions of tens of meV.
- The characteristic time for light-induced changes (~15 min) was substantially shorter than photopolymerization (~180 min).
Conclusions:
- BITh molecules effectively modify the work functions of Ag and Au.
- Light-induced work function modulation in BITh films is a rapid and reversible process.
- The observed phenomena suggest potential for light-controlled surface properties, distinct from photopolymerization.
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