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arXiv · 2004.12845

Spaced TiO$_2$ Nanotube Arrays Allow for High Performance Hierarchical Supercapacitor Structure

Nhat Truong Nguyen·Selda Ozkan·Imgon Hwang·Xuemei Zhou·Patrik Schmuki
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Abstract

In this work we describe the synthesis and electrochemical properties of nitridated hierarchical TiO$_2$ nanotubes as an electrode for supercapacitors. The hierarchical TiO$_2$ nanostructures are formed by a controlled layer-by-layer TiO2 nanoparticle decoration on self-organized spaced TiO$_2$ nanotubes. These structures are then annealed in NH$_3$ atmosphere at elevated temperature to convert the material to a nitride structure -- this drastically enhances their electron-transport properties. The areal capacitance of hierarchical structures can be tuned by changing the number of decorated TiO$_2$ nanoparticle layers. The capacitance enhancement of the hierarchical structures reaches a maximum when the surface area through nanoparticle deposition is highest and the conductivity via nitridation is optimized.

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Nhat Truong Nguyen, Selda Ozkan, Imgon Hwang, Xuemei Zhou, Patrik Schmuki. 2020-04-14. Spaced TiO$_2$ Nanotube Arrays Allow for High Performance Hierarchical Supercapacitor Structure. https://doi.org/10.1039/c6ta10179h

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