Compositing effects for high thermoelectric performance of Cu₂Se-based materials

Area of Science:

• Materials Science
• Energy Science
• Solid State Physics

Background:

• Thermoelectric materials convert heat to electricity, crucial for waste heat recovery.
• Copper selenide (Cu2Se) shows high thermoelectric potential but suffers from poor stability and low carrier mobility due to its superionic nature.

Purpose of the Study:

• To enhance the thermoelectric performance and service stability of Cu2Se-based materials.
• To optimize carrier mobility and reduce lattice thermal conductivity through in-situ compositing and interface engineering.

Main Methods:

• Utilized self-propagating high-temperature synthesis for in-situ compositing of BiCuSeO and Cu2Se.
• Introduced graphene at interfaces to improve carrier mobility and enhance phonon scattering.

Main Results:

• Achieved a maximum thermoelectric figure of merit (ZTmax) of ~2.82 at 1000 K.
• Obtained an average ZT (ZTave) of ~1.73 over a wide temperature range (473 K to 1000 K).
• Demonstrated improved service stability and significantly enhanced carrier mobility.

Conclusions:

• The developed Cu2Se-BiCuSeO-graphene composites offer a facile and effective strategy for high-performance thermoelectric applications.
• This approach provides a pathway to overcome limitations in traditional Cu2Se-based thermoelectric materials.
• The findings have broad implications for improving thermoelectric systems and waste heat recovery technologies.