Enhancement of thermoelectric power factor in NaxCoO2/Au multilayers

Xiaohui Zhao , Haifeng Wang , Shufang Wang , El Hadj Dogheche (1, 2) , Jianglong Wang , Guangsheng Fu

1 IEMN-DOAE - Institut d’Électronique, de Microélectronique et de Nanotechnologie - Département Opto-Acousto-Électronique - UMR 8520
2 OPTO - IEMN - Optoélectronique - IEMN

NaxCoO2/Au thin film multilayers, with a thickness of the Au layer of 0.5–12 nm, have been fabricated on c-Al2O3 by post annealing of the CoO/Au thin film multilayers in Na vapor at high temperature in air. X-ray diffraction measurements revealed that the resulting NaxCoO2 layer was c-axis oriented with perfect ab-plane alignment and there was no reaction between Au and NaxCoO2. The resistivity of the NaxCoO2/Au multilayers decreased significantly with increasing the volume fraction of the Au layer without obvious deterioration of the Seebeck coefficient. Consequently, a considerable enhancement of the power factor was achieved in NaxCoO2/Au multilayers with the right Au volume fraction, which was about 2.2 times larger than that of the single NaxCoO2 layer with the same thickness.

Domaines: Optique / photonique; Acoustique [physics.class-ph]

Xiaohui Zhao, Haifeng Wang, Shufang Wang, El Hadj Dogheche, Jianglong Wang, et al.. Enhancement of thermoelectric power factor in NaxCoO2/Au multilayers. RSC Advances, 2014, 4 (100), pp.57148-57152. ⟨10.1039/C4RA07319C⟩. ⟨hal-03560771⟩