Molecular interfaces for plasmonic hot electron photovoltaics.

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Plasmonic hot-electron Schottky solar cells offer potential for efficient energy conversion.
• Tailoring interfacial properties is crucial for optimizing device performance.
• Self-assembled monolayers (SAMs) provide a versatile platform for surface modification.

Purpose of the Study:

• To investigate the use of SAMs for improving photovoltaic performance in plasmonic hot-electron Schottky solar cells.
• To demonstrate the simultaneous control of key photovoltaic parameters using SAMs.
• To achieve record efficiencies for this class of solar cells.

Main Methods:

• Utilizing SAMs with tunable molecular parameters (length, dipole moment, functionalization).
• Engineering the interface between plasmonic nanoparticles and the semiconductor.
• Characterizing photovoltaic performance, including open-circuit voltage, short-circuit current, fill-factor, and IPCE.

Main Results:

• Achieved simultaneous control over open-circuit voltage, hot-electron injection, and short-circuit current.
• Demonstrated high open-circuit voltages (0.56 V) and fill-factors (0.58).
• Obtained external quantum efficiency (IPCE) above 5% at plasmon resonance and a record power-conversion efficiency of 0.11% for this device type.

Conclusions:

• SAMs are effective in simultaneously optimizing multiple parameters of plasmonic hot-electron Schottky solar cells.
• Molecular engineering of SAMs offers a precise method for enhancing solar cell performance.
• This approach sets a new benchmark for efficiency in plasmonic solar cell technology.