Research

1. Van der Waals Gap Engineering for High-Mobility Thermoelectrics

Our group develops precise intercalation-based strategies that insert dopants directly into the van der Waals (vdW) gaps of layered Bi–Te–Se/Sb quantum material systems.
This unique structural degree of freedom enables:

•Modulation doping with spatially separated charge donors

•Enhanced mobility while suppressing ionized-impurity scattering

•Simultaneous phonon scattering and c-axis lattice expansion

Our vdW-gap engineering has achieved record power factor and ZT in both n-type Bi2Te2.7Se0.3 and p-type Bi0.5Sb1.5Te3, demonstrating its broad universality.

2. Interfacial Band Engineering and Energy Filtering

We engineer nanoscale Ag₂Se/SiOx interfaces that create controlled energy barriers.
These interfaces enable:

•Selective transmission of high-energy carriers (energy filtering)

•Seebeck enhancement without degrading electrical conductivity

•Suppressed lattice thermal conductivity via interface phonon scattering

This work establishes a robust route for interfacial band modulation in room-temperature thermoelectrics.

3. Advanced thermal property measurements

We connect microstructure and transport across these different scales.
Using our custom 3ω platform, we directly measure in-plane thermal conductivity of sputtered Bi0.5Sb1.5Te3 films as low as 0.3 W/m·K, enabling ZT ≈ 1.86 near room temperature.

4. Mechanism-Driven Thermoelectrics: Electron–Phonon Coupling, Kohn Anomalies, and Fermi Surface Nesting

Beyond performance optimization, we uncover fundamental mechanisms that govern ZT.
In GeTe-based materials, we demonstrated:

•Kohn anomaly in phonon dispersion (INS)

•1D-like nested Fermi surface topology

•Exceptionally strong electron–phonon coupling

•Ultralow lattice thermal conductivity leading to ZT ≈ 2.7

This mechanism-level insight sets a high bar for physics-based thermoelectric design

5. Electrochemical Energy Materials & MOF-Derived LDH Supercapacitors

Our electrochemical research program focuses on engineering MOF-derived, multi-metal LDH nanosheets as high-performance pseudocapacitive electrodes. By leveraging ordered MOF frameworks, synergistic polymetallic redox centers, and EIS-guided transport analysis, we create scalable, binder-free electrode architectures capable of delivering high capacitance (>1000 F/g) and excellent stability. This work establishes a clear design platform for next-generation supercapacitors and electrochemical energy technologies.

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