Department of Power Mechanical Engineering, National Tsing Hua University

Nian-Kuei Tsou (鄒年奎 ) (Research student), Che-Wun Hong (洪哲文 ) (Professor)

First-Principles Investigation on Quantum Dot Photoelectric First-Principles Investigation on Quantum Dot Photoelectric Properties to Enhance the Photoelectrochemical Solar Cell Properties to Enhance the Photoelectrochemical Solar Cell

PerformancePerformance 第一原理計算量子點光電性質提升光電化學太陽電池效能研究第一原理計算量子點光電性質提升光電化學太陽電池效能研究

ObjectivesObjectives•To investigate the optimal sunlight absorption by adjusting the quantum dot size to enhance the solar cell performance.•To find out the suitable bond mode between quantum dots and the TiO2 electrode to make electron injection into TiO2 easier and prevent recombination.

TiOTiO22 Surface Unit Cell Surface Unit Cell(CdSe)(CdSe)nn Energy Gap and Level Energy Gap and Level

2

2,, ,

2

KSKS KSt

i v t tt m

rr r

2

30

0

1 , , , ,

4KS

ext xc

ewhere v t v t d r t v t

r r r rr r

Time Dependent Kohn-Sham Time Dependent Kohn-Sham EquationEquation

Quantum Dot Sensitized Solar Quantum Dot Sensitized Solar Cell and Electron Recombination Cell and Electron Recombination

Mechanism Mechanism

(CdSe)(CdSe)nn Clusters Clusters andandMolecular OrbitalsMolecular Orbitals

Solvent EffectSolvent Effect

Energy Gap-ExperimentEnergy Gap-Experiment

HH22O Absorbed on TiOO Absorbed on TiO22

(CdSe)(CdSe)nn Absorbed on TiO Absorbed on TiO22