Enhanced optical and thermoelectric properties of Ti doped half - Heusler alloy NbRuP: A first principles study

The effect of Titanium (Ti) doping on structural, electronic, optical and thermoelectric properties of NbRuP half - Heusler alloy was investigated. These properties were investigated by using density functional theory (DFT) with GGA, GGA + U, modified Becke-Johnson (mBJ) exchange, and spin orbit coupling (SOC) methods. The full Potential (FP) linearized augmented plane wave (LAPW) approach as implemented in WIEN2k code is used. The optimized lattice parameters for pure and doped alloys are 5.85 angstrom and 5.84 angstrom. The density of states (DOS) and band structure were also investigated. Results revealed that NbRuP alloy exhibit the semiconducting nature whereas the doped Nb0 center dot 75Ti0 center dot 25RuP compound shows the metallic behaviour. The DOS results revealed that the alloys show non magnetic behaviour. The optical conductivity, absorption coefficient, electron e-loss, refractive index and extinction coefficient are calculated using real and imaginary sections of dielectric function. The refractive index of doped alloy is 5.8 which is substantially higher than GaAs (3.2-3.8) and quite close to that of Ge (5.9). These optical properties make the doped material as an appropriate candidate for optoelectronic and solar cell applications. The effect of temperature on the electrical conductivity, Seebeck coefficient and Power factor were also investigated. Results showed that the doping of Ti in pure NbRuP increases the electric conductivity and power factor under TB-mBJ and SOC approaches which makes the alloy as potential candidate for thermoelectric energy applications.

Automated summary

The effect of Ti doping on the structural, electronic, optical and thermoelectric properties of NbRuP alloy was studied using density functional theory. The doped compound showed metallic behavior with high refractive index, making it suitable for optoelectronic and solar cell applications. Furthermore, the Ti doping increased the electrical conductivity and power factor of the alloy, making it a potential candidate for thermoelectric energy applications.