Improvement of photocatalytic activity of brookite titanium dioxide nanorods by surface modification using chemical etching

► Brookite TiO2 nanorods were easily etched from the tip faces in H2O2-NH3 solution and exposed new surfaces after etching. ► Brookite TiO2 nanorods were stable against H2SO4 at room temperature, while were greatly etched in H2SO4 at 200 °C. ► The formation of new exposed crystal faces by H2O2-NH3 etching improved separation of redox sites due to its high oxidation ability.