Analyzing the physical properties of perovskite oxides CeBO<sub>3</sub> (B=Be, Mg) for optoelectronic and thermoelectric applications
Aissani Ali, Besbes Anissa, Djelti Radouan, İlknur Kars Durukan
Abstract
The structural, electronic, elastic, thermoelectric and optical properties of CeBO 3 (B = Be, Mg) oxide perovskites were investigated using density functional theory. Exchange and correlation effects were addressed through the GGA approximation and the TB-mBJ potential. Thermodynamic stability was confirmed by assessing cohesive energy and formation enthalpy. The band structures reveal a semiconductor nature with a moderate indirect band gap of 0.73 (CeBeO 3 ) and 0.51 (CeMgO 3 ). The TB-mBJ approximation has enhanced the gap value with a 55% approaching rate. These compounds exhibited a rigid and elastically anisotropic behavior with chemical bonds manifesting as a mixture of metallic and covalent types. The CeBeO 3 displayed ductility while CeMgO 3 exhibited brittleness. The optical examination suggests that these oxides exhibit activity across a broad range of the electromagnetic spectrum. Their strong reflectivity in the near-infrared region was particularly noteworthy suggesting potential use as effective shields in this domain. The replacement of beryllium with a magnesium atom enhanced thermoelectric performance by reducing thermal conductivity and increasing the merit factor. Based on the obtained results, the semiconductor perovskites CeBeO 3 and CeMgO 3 hold promise for efficient applications in optical and thermoelectric devices.