Resumen de New CaRbNaZ (Z=Si and Ge) semiconductor compounds suitable for photovoltaic and thermoelectric devices (12 pages)
A. Righi, F. Bendahma, A. Labdelli, M. Mana, R. Khenata, T. Seddik, G. Ugur, W. Ahmed
Semiconductor compounds are a fascinating type of materials that have attracted the attention of scientists because of their ability to enhance green technology by efficiently converting, storing, and transmitting waste heat into electrical energy. This research aimed to investigate the structural, electronic, elastic, optical, and thermoelectric characteristics of newly developed Quaternary Heusler alloys (QHAs) CaRbNaZ (where Z represents Si and Ge). This was achieved using the generalized gradient approximation (GGA) and the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. For both approximations, CaRbNaSi and CaRbNaGe are found to be nonmagnetic semiconductors with band gaps varying in the range from 0.49 to 1.00 eV. The studied alloys additionally conform to the Slater-Pauling rule, exhibiting a specific magnetic moment of M_(tot)= 8 – Z_(tot) for nonmagnetic behavior and, therefore, having a total magnetic of 0.00 µ_(B). They possess an optical band gap comparable to the electronic band gap, along with significant absorption properties (90 × 10^(4) and 103 × 10^(4) cm^(−1)) in visible and UV regions, respectively, proving that these compounds are promising materials for photovoltaic cells and UV radiation shields. The high merit factor values (0.76 and 0.80) at 300K confirm that CaRbNaZ (Z= Si and Ge) are suitable candidates for thermoelectric devices.
