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arXiv · 1904.03284

Facile and time-resolved chemical growth of nanoporous CaxCoO2 thin films for flexible and thermoelectric applications

Tridib Kumar Sinha·Jinho Lee·Jin Kuk Kim·Samit K. Ray·Biplab Paul
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Abstract

CaxCoO2 thin films can be promising for widespread flexible thermoelectric applications in a wide temperature range from room-temperature self-powered wearable applications (by harvesting power from body heat) to energy harvesting from hot surfaces (e.g., hot pipes) if a cost-effective and facile growth technique is developed. Here, we demonstrate a time resolved, facile and ligand-free soft chemical method for the growth of nanoporous Ca0.35CoO2 thin films on sapphire and mica substrates from a water-based precursor ink, composed of in-situ prepared Ca2+-DMF and Co2+-DMF complexes. Mica serves as flexible substrate as well as sacrificial layer for film transfer. The grown films are oriented and can sustain bending stress until a bending radius of 15 mm. Despite the presence of nanopores, the power factor of Ca0.35CoO2 film is found to be as high as 0.50 x 10-4 Wm-1K-2 near room temperature. The present technique, being simple and fast to be potentially suitable for cost-effective industrial upscaling.

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Tridib Kumar Sinha, Jinho Lee, Jin Kuk Kim, Samit K. Ray, Biplab Paul. 2019-04-05. Facile and time-resolved chemical growth of nanoporous CaxCoO2 thin films for flexible and thermoelectric applications. https://doi.org/10.1039/c9cc03441b

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