Transient Absorption Spectroscopy

2In the femtosecond transient absorption (fs-TA) technique a femtosecond pump pulse creates initial excited states, which are detected through changes in the transmission of a time-delayed probe pulse. In our lab, fs-TA experiments on quantum dot (QD) systems use UV or visible light as the pump, and white light continuum (WLC) as the probe, which can monitor electronic transitions. Meanwhile, we can also use mid-IR probe pulses obtained by difference-frequency mixing of two near-IR pulses provide an alternative way to study QD intraband transitions. This technique allow us to study the interfacial charge separation dynamics in photovoltaic nanomaterials.

 


Selected Publications

Haiming Zhu, Ye Yang, Kaifeng Wu, Tianquan Lian,  ”Charge Transfer Dynamics from Photoexcited Semiconductor Quantum Dots”, Annu. Rev. Phys. Chem., 2016, 67,1
Kaifeng Wu, Tianquan Lian, ”Quantum confined colloidal nanorod heterostructures for solar-to-fuel conversion” Chem. Soc. Rev., 201645, 3781-810.
Kaifeng Wu, Haiming Zhu, Tianquan Lian, ”Ultrafast Exciton Dynamics and Light-Driven H2 Evolution in Colloidal Semiconductor Nanorods and Pt-Tipped Nanorods” Acc. Chem. Res., 2015, 48, 851–859

 


Other research Fields

Sum Frenquency Generation

Single Molecule Fluorescence