FeOOH Composite Electrode Based on TiN Nanopetals for High-Performance Supercapacitors

In this work, a new strategy is proposed for the facile synthesis of a TiO2 nanopetal-like film on a titanium substrate, which includes anodization of titanium and subsequent H3PO4 treatment. TiO2 nanopetals can be perfectly converted to TiN nanopetals by nitridation. Due to the combined effect of high conductivity of TiN and the open structure of nanopetals, the TiN nanopetals should be a suitable scaffold for loading other active materials for supercapacitors. As an example, the FeOOH composite electrode based on TiN nanopetals (TiN@FeOOH) is achieved by electrodeposition of a FeOOH film onto TiN nanopetals. The obtained composite nanopetal electrode shows a high specific capacitance of 1564.0 F g(-1) (based on the mass of FeOOH) and good cyclic stability with a capacitance retention of 83.5% after 5000 cycles. Furthermore, the novel nanopetal architectures may be further applied in other areas, e.g., solar cells, high-performance rechargeable Li-ion batteries, and photocatalysis.