Executive Summary : | The concept of sustainable energy harvesting through thermoelectric (TE) materials relies on finding nontoxic, earth-abundant, and stable materials. The figure of merit (ZT) is crucial for determining the quality of a TE material, which must have low κ and moderately higher σ. Optimal defect engineering in earth-abundant, environment-friendly, and stable perovskites (ABO₃) or layered perovskites can lead to new avenues in TE research. However, the complexity of their configurational space makes it difficult to experimentally scan all possible dopants/defects for better TE performance. Computational search within the framework of density functional theory can help reduce this complexity by predicting plausible materials with desired properties. Recent theoretical understandings suggest that Ca doping at A-site in LaNiO₃ increases stability and electron conduction, which in turn increases the power factor (PF=σs²). substitution of La3+ with Ca2+ promotes O-vacancies, which may act as phonon scatterer. Increase in oxygen deficiency provides additional carriers, which would improve PF. Co-substitution in A- and B-sites with Ca and Fe improves carrier concentration. The fundamental understanding of structure-TE properties correlation and lattice dynamics is key to successful design of functional TE materials. Phon dispersion calculations will be carried out to investigate structural changes. A high-temperature seebeck apparatus will be designed and developed at the UGC-DAECsR Indore for thermal power measurements of a broad range of materials, including perovskites. |