MAIN CHARACTERISTICS OF THERMOELECTRIC MATERIALS PRODUCED THROUGH QUALITY CONTROL OF GRANULATED NANOPARTICLES WITH SIO2 INCLUSIONS

Abstract

The global demand for high-efficiency energy conversion systems has put nanostructured thermoelectric (TE) materials at the forefront of materials science. This study provides an in-depth investigation into the synergistic effects of SiO₂ nanoparticle granulation and rigorous quality control (QC) on the dimensionless figure of merit (ZT). Silicon dioxide, acting as a secondary phase, was processed through a precise spray-drying technique to form controlled granulated precursors. Our findings demonstrate that maintaining a strict granule size distribution and structural integrity during Spark Plasma Sintering (SPS) leads to a dramatic reduction in lattice thermal conductivity κ₁ by 35-40 %. The study highlights how quality-controlled granulation prevents the common pitfalls of nanoparticle agglomeration, thereby maintaining electrical conductivity while enhancing phonon scattering. This methodology offers a scalable pathway for the industrial production of high-performance TE modules for waste heat recovery.