The 67th JSAP Spring Meeting 2020

Presentation information

Oral presentation

12 Organic Molecules and Bioelectronics » 12.5 Organic solar cells

[15a-A402-1~10] 12.5 Organic solar cells

Sun. Mar 15, 2020 9:00 AM - 11:45 AM A402 (6-402)

Takaya Kubo(Univ. of Tokyo), Nobuyuki Matsuki(Kanagawa Univ.)

9:30 AM - 9:45 AM

[15a-A402-3] Long lifetime of hot electrons in TiO2 nanoparticles for high-efficiency charge transfer

Bochao Li1, Hao Li1, Chang Yang1, Boyu Ji1, Jingquan Lin1, 〇Toshihisa Tomie1,2 (1.CUST, 2.AIST NERI)

Keywords:TiO2 nanoparticles, charge tansfer efficiency, long lifetime hot electrons

The lifetime of hot electrons in metals is as short as 10fs. When the lifetime is only 10 fs, 1 to 2 eV electrons travel less than 10 nm. For transferring electrons over several hundred nm in solar cells, a lifetime longer than several hundred fs is required. Thus, a long lifetime of electrons is crucially important for the high-transfer efficiency of carriers.
We evaluated the lifetime of hot electrons by the pump-probe technique by observing photoemission using PEEM. We found the lifetime of electrons is s long as 1 ps in TiO2 nanoparticles, which is ten times longer than in a TiO2 single crystal. Thus we confirmed that the long lifetime of hot electrons is the secret of high performance of TiO2 nanoparticles.