Rational design of 3D dendritic TiO₂ nanostructures with favorable architectures

Controlling the morphology and size of titanium dioxide (TiO₂) nanostructures is crucial to obtain superior photocatalytic, photovoltaic, and electrochemical properties. However, the synthetic techniques for preparing such structures, especially those with complex configurations, still remain a challenge because of the rapid hydrolysis of Ti-containing polymer precursors in aqueous solution. Herein, we report a completely novel approach-three- dimensional (3D) TiO₂ nanostructures with favorable dendritic architectures-through a simple hydrothermal synthesis. The size of the 3D TiO₂ dendrites and the morphology of the constituent nano-units, in the form of nanorods, nanoribbons, and nanowires, are controlled by adjusting the precursor hydrolysis rate and the surfactant aggregation. These novel configurations of TiO₂ nanostructures possess higher surface area and superior electrochemical properties compared to nanoparticles with smooth surfaces. Our findings provide an effective solution for the synthesis of complex TiO₂ nano-architectures, which can pave the way to further improve the energy storage and energy conversion efficiency of TiO ₂-based devices.