Programme

O.9 -- Oral, NCTP-39

Date: Tuesday, 29-07-2014

Time: 14h00 - 14h20

Density Functional Based Tight Binding Study on Photoelectronic Processes at Porphyrin Dye/ZnO/ZnS Core/shell Nanowire Heterostructures in Dye-Sensitized Solar Cells

Vu Ngoc Tuoc1 , Tran Doan Huan2 , Le Thi Hong Lien1 and Nguyen Thi Thao1

1Institute of Engineering Physics, Hanoi University of Science and Technology, 01 Dai Co Viet Rd., Hanoi 1000, Vietnam 2Institute of Materials Science, University of Connecticut, Storrs, CT 06269-3136 USA

High performance Dye-sensitized solar cells (DSSCs) are very attractive as they are based on inexpensive semiconductor materials, e.g. TiO2, ZnO sensitized to visible light absorption with dyes covalently attached to the semiconductor surface by molecular linkers. Here we report a Density Functional Based Tight Binding (DFTB) study on photo induced electron injection efficiencies from modular assemblies of a Zn-porphyrin dye complex covalently bound to the core/shell nanowire heterostructures of ZnO/ZnS. The band energy alignment, band structure, density of states, and band edge wave functions of this nanowire nano heterostructure in the DSSC are found to depend on the core radius and shell thickness. Nevertheless there always indicated clearly the spatial charge separation in this DSSC system which prevent the charge recombination and thereby increasing the chance of better photovoltaic performance.

Presenter: Vu Ngoc Tuoc