TREE-LIKE NANOSTRUCTURED POLYMER/INORGANIC METAL OXIDE HYBRID PHOTOVOLTAIC DEVICES
Y.-Y. Lina), T.-H. Chua), C.-W. Chena,*), J.-J. Wub), W.-F. Sua)
a)Department of Materials Science and Engineering, National Taiwan University 106, Taiwan
b) Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
We have proposed a tree-like nanostructured photovoltaic device based on the polymer (P3HT)/metal oxide hybrid materials. An array of ZnO nanorods with a larger size of 30 nm in diameter and 100 nm in length are grown to act as tree trunks for efficient charge collection. TiO2 nanorods with a size of 5nm in diameter and 30 nm in length are incorporated to act as tree branches for facilitating charge separation and transport. The device based on the tree-like nanostructure exhibits a short circuit current density >2 mA/cm2 under A.M. 1.5 illumination, over seven times increase compared to that without the incorporation of TiO2 nanorods. Efficient charge separation and transport in the tree-like nanostructured photovoltaic device has further been demonstrated by time-resolved photoluminescence spectroscopy and transient photocurrent measurements.