Scalable spin Seebeck thermoelectric generation using Fe-oxide nanoparticle assembled film on flexible substrate

We fabricated Fe3O4 nanoparticle (NP)-assembled films on flexible polyimide sheets with Pt or Ta cap layer using a spin coating method and DC sputtering. The films were elaborated for spin Seebeck thermoelectric generator applications, and their spin Seebeck voltages were observed. We showed that the thermoelectric power of [Pt film/Fe3O4 NP](n) multilayered films increases with increasing number of stacking n. Additionally, we prepared spin Seebeck thermopile devices in which the Fe3O4 NP-assembled films capped by Pt and Ta are connected alternately in series. We demonstrated that spin Seebeck voltages of the thermopile devices are larger than those of single [Pt or Ta film/Fe3O4 NP](n) piece. Our results indicate that the spin Seebeck thermoelectric power of Fe3O4 NPs can be enhanced using a simple fabrication process without lithography technique.

Automated summary

In this study, Fe3O4 nanoparticle-assembled films were prepared for spin Seebeck thermoelectric generator applications. It was observed that the thermoelectric power of multilayered films increases with the number of stacking, and the thermopile devices show higher voltages.