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Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells
Published on: November 5, 2014
Electronic junction control in a nanotube-semiconductor Schottky junction solar cell
Pooja Wadhwa1, Bo Liu, Mitchell A McCarthy
1Department of Physics.
Nano Letters
|November 5, 2010
Summary
Researchers used single-wall carbon nanotubes to actively control solar cell efficiency. This electronic modulation of the nanotube-silicon junction allows for tunable power conversion efficiency (PCE) from 4% to 11%.
Area of Science:
- Materials Science
- Nanoscience
- Renewable Energy
Background:
- Schottky junction solar cells offer potential for efficient energy conversion.
- Carbon nanotubes possess unique electronic properties exploitable in device applications.
- Controlling the interface properties of nanotube-semiconductor junctions is key to optimizing performance.
Purpose of the Study:
- To demonstrate active electronic modulation of Fermi level offset in nanotube-Si solar cells.
- To investigate the impact of this modulation on the built-in potential and power generation.
- To achieve tunable power conversion efficiency (PCE) in nanotube-Si Schottky junction devices.
Main Methods:
- Fabrication of nanotube-Si Schottky junction solar cells.
- Exploitation of the low density of electronic states in single-wall carbon nanotubes.
- Application of electronic modulation to alter Fermi level offset and junction properties.
Main Results:
- As-produced devices showed approximately 8.5% power conversion efficiency (PCE).
- Active electronic modulation continuously and reversibly tuned the PCE.
- Achieved a PCE range from 4% to 11% through modulation.
Conclusions:
- Active electronic modulation of the Fermi level offset is feasible in nanotube-Si solar cells.
- This modulation significantly impacts the built-in potential and device performance.
- The developed method allows for dynamic control over solar cell power conversion efficiency.
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