Excited-State Dynamics in Colloidal Semiconductor Nanocrystals

Abstract

Colloidal semiconductor nanocrystals have attracted continuous worldwide interest over the last three decades owing to their remarkable and unique sizeand shape-, dependent properties. The colloidal nature of these nanomaterials allows one to take full advantage of nanoscale effects to tailor their optoelectronic and physical-chemical properties, yielding materials that combine size-, shape-, and composition-dependent properties with easy surface manipulation and solution processing. These features have turned the study of colloidal semiconductor nanocrystals into a dynamic and multidisciplinary research field, with fascinating fundamental challenges and dazzling application prospects. This review focuses on the excited-state dynamics in these intriguing nanomaterials, covering a range of different relaxation mechanisms that span over 15 orders of magnitude, from a few femtoseconds to a few seconds after photoexcitation. In addition to reviewing the state of the art and highlighting the essential concepts in the field, we also discuss

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“…(b) Schematic illustration of the quantum confinement effect in QDs: with decreasing particle size, quantum confinement and hence the bandgap increase, leading to progressive blue shifts in the particles’ PL profiles. Adapted with permission from refs and . Copyright 2017 Springer International Publishing AG; Copyright 2011 Royal Society of Chemistry.…”

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