Direct preparation of La-doped SrTiO3 thermoelectric materials by mechanical alloying with carbon burial sintering

摘要

Thermoelectric Sr1-xLaxTiO3 (x = 0, 0.02, 0.05, 0.08) nanoparticles were directly prepared by mechanical alloying, followed by carbon burial sintering to produce the bulk counterparts, for the purpose of obtaining pure phase and fine microstructures in a facile process. Electrical and thermal transport properties have been measured over the temperature range from 300 K to 1100 K. La was successfully doped into the SrTiO3 during the milling process and acted as an n-type dopant. Core structure and superstructure in bulk samples, leads to a relatively high absolute Seebeck coefficient. The dimensionless figure-of-merit ZT changes with the increasing of La content and temperature, and the maximum ZT value can reach 0.06 at 300 K for x = 0.02 and 0.20 at 1000 K for x = 0.08. This strategy for bulk thermoelectric materials is simple, cost-effective and has great potential in large-scale industrial applications.