Unknown

Dataset Information

0

Observation of a phonon bottleneck in copper-doped colloidal quantum dots.


ABSTRACT: Hot electrons can dramatically improve the efficiency of solar cells and sensitize energetically-demanding photochemical reactions. Efficient hot electron devices have been hindered by sub-picosecond intraband cooling of hot electrons in typical semiconductors via electron-phonon scattering. Semiconductor quantum dots were predicted to exhibit a "phonon bottleneck" for hot electron relaxation as their quantum-confined electrons would couple very inefficiently to phonons. However, typical cadmium selenide dots still exhibit sub-picosecond hot electron cooling, bypassing the phonon bottleneck possibly via an Auger-like process whereby the excessive energy of the hot electron is transferred to the hole. Here we demonstrate this cooling mechanism can be suppressed in copper-doped cadmium selenide colloidal quantum dots due to femtosecond hole capturing by copper-dopants. As a result, we observe a lifetime of ~8.6 picosecond for 1Pe hot electrons which is more than 30-fold longer than that in same-sized, undoped dots (~0.25 picosecond).

SUBMITTER: Wang L 

PROVIDER: S-EPMC6778069 | BioStudies | 2019-01-01

REPOSITORIES: biostudies

Similar Datasets

2018-01-01 | S-EPMC5998019 | BioStudies
2014-01-01 | S-EPMC3977796 | BioStudies
1000-01-01 | S-EPMC4418885 | BioStudies
2017-01-01 | S-EPMC5492216 | BioStudies
2018-01-01 | S-EPMC6102289 | BioStudies
2017-01-01 | S-EPMC5670184 | BioStudies
2017-01-01 | S-EPMC5309769 | BioStudies
2013-01-01 | S-EPMC3600480 | BioStudies
2019-01-01 | S-EPMC6354726 | BioStudies
2017-01-01 | S-EPMC5379476 | BioStudies