[21a-432-1~12] 12.5 Organic solar cells

[21a-432-12] Ionization energy of individual TiO2 nanoparticles observed by PEEM

Bochao Li¹, Chang Yang¹, Hao Li¹, Boyu Ji¹, Jingquang Lin¹, 〇Toshihisa Tomie^1,2 (1.CUST, 2.AIST)

Keywords:TiO2, ionization energy, individual nano particle

We are observing electronic states of individual NPs using a photoemission electron microscope (PEEM) having a spatial resolution of 40-nm with a pump and probe method using a fs laser.
We found 20 % of NPs have a lager ionization energy by about 0.2 eV than others. This difference may be caused by different density of defects or different facet or by other reasons causing a change of work function.