Biomimetic CNT@TiO2 composite with enhanced photocatalytic properties

Two kinds of CNT@TiO2 biomimetic composites with needle-leaved (NL) and broad-leaved (BL) trees morphology were synthesized respectively by a simple one-step solvothermal method for the first time. The TiO2 leaves located on CNT stems act as active sites for photocatalysis. The method allows one to prepare the composites with distinguish morphology of TiO2 leaves by adjusting the mass ratio of CNT and TiO2. In the photodegradation test of methylene orange, the reaction rate up to eightfold increment was observed with both the biomimetic composites compared to bare TiO2. The improved photocatalytic activity could be owed to two aspects, namely the enhanced light trapping and scattering ability benefited from large specific area and the direct transport pathway for electrons conducted by CNT, which all derive from the advantages of the unique tree-like structure. This work presents a new strategy to synthesize hetero-photocatalysts with maximized light-harvesting efficiency and low electron hole recombination rate concurrently. These results demonstrate the great potential of biomemic composites and would stimulate further research in photocatalysis and related areas. (C) 2015 Elsevier B.V. All rights reserved.