Thermoelectrics in misfit-layered oxides [(Ca,Ln)2CoO3]0.62[CoO2]: From bulk to nano

► Highly-textured nano-sized [(Ca,Ln)2CoO3]0.62[CoO2] compacts are successfully fabricated by a simple cold-pressure method. ► These nanocompacts exhibit a high thermoelectric efficiency. ► The high ZT value that exceeds 0.45 at 1000 K is maintained after intensive thermal cycling in air. ► This nanosystem could be a promising thermoelectric oxide for high temperature applications.