As a representative of PGEC thermoelectric (TE) materials, the filled-skutterudite is one of the most promising thermoelectric materials. Recently the indium-doped CoSb3 reportedly showed high thermoelectric performance, but there is an argument on whether the indium can be filled into the CoSb3. A high ZT value of 1.43 was achieved in the InxCeyCo4Sb12 skutterudites for its nanocomposite structure with the in-situ nano-InSb particles in CoSb3 crystal boundaries. However, it was unknown whether the in-situ ...