Thermal Recovery of Colloidal Quantum Dot Ensembles Following Photoinduced Dimming.

J Phys Chem Lett

Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.

Published: August 2015

Colloidal CdSe quantum dot (QD) core ensembles were photodimmed and allowed to recover in the dark using ambient thermal energy at a range of temperatures. Nonlinear thermal recovery is well described by a stretched exponential function, and further analysis yields an underlying probability distribution of rate constants. Casting the rate constants as a collection of first-order activated processes provides an activation barrier probability distribution with significant density at room-temperature thermal energy that peaks at 200 meV before decaying to zero. This treatment for the recovery transition intuitively describes the distributed kinetics observed and complements commonly proposed blinking mechanisms.

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http://dx.doi.org/10.1021/acs.jpclett.5b00989DOI Listing

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