Understanding The Transport Properties of YNiBi Half-Heusler Alloy: An Ab-Initio Study

In the present work, we have studied the electronic and transport properties of YNiBi half-Heusler alloy by combining the first principles methods with the Boltzmann transport theory. The electronic band structure and total density of states plot suggest the presence of semiconducting ground state in the compound. The value of indirect band gap is found to be similar to 0.21 eV. The origin of the band gap is associated primarily with the interaction between the Ni 3d and the Y 4d states. The room temperature value of Seebeck coefficient is similar to 230 mu VK-1. A moderate power factor of about 12x10(14) mu Wcm(-1) K-2 s(-1) is obtained at 980 k.