Thermoelectric properties of inhomogeneous BCN alloy nanotubes

The thermoelectric properties of inhomogeneous BCN alloy nanotubes are investigated using a first-principles approach and the non-equilibrium Green’s function method based on virtual crystal approximation. The asymmetric distribution of B, C, and N atoms in these nanotubes causes tilted transmission probabilities around the Fermi level, disrupting electron–hole symmetry under varying temperature gradients. Consequently, the thermal charge currents exhibit fascinating behaviors like negative differential thermal resistance and thermoelectric current switching. Reducing the carbon concentration leads to decreased electrical conductance, electronic thermal conductance and Lorenz number but increased Seebeck coefficient and figure of merit. This emphasizes the significance of carbon concentration in tuning the thermoelectric efficiency of these nanotubes, suggesting a possibility for tailored thermoelectric nanomaterial design.