Charge Carrier Relaxation in Colloidal FAPbI3 Nanostructures Using Global Analysis

Carrier Multiplication Mechanisms and Competing Processes in Colloidal Semiconductor Nanostructures

Quantum confined semiconductor nanoparticles, such as colloidal quantum dots, nanorods and nanoplatelets have broad extended absorption spectra at energies above their bandgaps. This means that they can absorb light at high photon energies leading to the formation of hot excitons with finite excited state lifetimes. During their existence, the hot electron and hole that comprise the exciton may...

Slow hot-carrier relaxation in colloidal graphene quantum dots.

Reducing hot-carrier relaxation rates is of great significance in overcoming energy loss that fundamentally limits the efficiency of solar energy utilization. Semiconductor quantum dots are expected to have much slower carrier cooling because the spacing between their discrete electronic levels is much larger than phonon energy. However, the slower carrier cooling is difficult to observe due to...

Carrier relaxation dynamics in lead sulfide colloidal quantum dots.

We report transient absorption saturation measurements on lead sulfide colloidal nanocrystals at the first and second exciton energies and fit the results to a model incorporating intraband and interband relaxation processes. We study in detail the Auger recombination from the first excited state, which takes place when more than one electron-hole pair is excited in a dot. We find an Auger coef...

Charge Relaxation, Localization, and Separation in Colloidal Semiconductor Nanocrystals

Ultrafast charge carrier relaxation and charge transfer processes in CdS/CdTe thin films.

Ultrafast transient absorption pump-probe spectroscopy (TAPPS) has been employed to investigate charge carrier relaxation in cadmium sulfide/cadmium telluride (CdS/CdTe) nanoparticle (NP)-based thin films and electron transfer (ET) processes between CdTe and CdS. Effects of post-growth annealing treatments to ET processes have been investigated by carrying out TAPPS experiments on three CdS/CdT...