Hot Carrier-Based Near-Field Thermophotovoltaic Energy Conversion

Area of Science:

• Energy Conversion
• Materials Science
• Solid-State Physics

Background:

• Near-field thermophotovoltaics (NFTPV) enhances radiative heat transfer for efficient heat-to-electricity conversion.
• Conventional silicon photovoltaic (PV) cells are incompatible with NFTPV due to their bandgap limitations.
• Low bandgap III-V semiconductors, proposed for NFTPV, are experimentally challenging.

Purpose of the Study:

• To propose a novel approach for high-efficiency NFTPV using hot carrier PV cells.
• To demonstrate the potential of silicon-based Schottky junctions for NFTPV applications.
• To explore the feasibility of overcoming current limitations in NFTPV technology.

Main Methods:

• Investigated hot carrier PV cells based on Schottky junctions between silicon and metallic films.
• Analyzed the potential of hot carrier science to enhance quantum efficiency (QE) beyond Fowler model predictions.
• Optimized thermal radiation spectrum for hot carrier-based NFTPV systems.

Main Results:

• Hot carrier PV cells offer a promising solution for high-efficiency NFTPV.
• Potential for 10-30% conversion efficiencies and 10-500 W/cm² power densities at 900-1500 K.
• Extreme near-field thermal radiation properties are suitable for investigating high QE hot carrier junctions.

Conclusions:

• Hot carrier PV cells based on silicon and metallic films provide a viable path for experimental NFTPV demonstration.
• This approach overcomes the bandgap limitations of conventional silicon PV cells.
• The study is relevant to hot carrier science and advances NFTPV technology using conventional materials.