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Updated: Jan 1, 2026
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Charge Dynamics in Quantum-Dot-Acceptor Complexes in the Presence of Confining and Deconfining Ligands
1Pollard Institute, School of Electronic and Electrical Engineering, & Bragg Centre for Materials Research , University of Leeds , Leeds LS2 9JT , United Kingdom.
Abstract:
Nanocrystal surface functionalization is becoming widespread for applications exploiting fast charge extraction or ultrasensitive redox reactions. A variety of molecular acceptors are being linked to the dot surface via a new generation of organic ligands, ranging from neutral linkers to charge delocalizers. Understanding how core states interact with these molecular orbitals, localized outside the dot, is paramount for optimizing the design of efficient nanocrystal-acceptor conjugates. Here we look at two examples of this interaction: charge transfer to a molecular acceptor linked through either an exciton-delocalizing ligand or a more conventional localizing molecule. We find that such transfer can be described in terms of an Auger-mediated process whose rates can be tuned within a window of a few orders of magnitude (for the same dot-ligand-acceptor conjugate) by a suitable choice of the dispersion solvent and nanocrystal's dielectric environment. This result provides clear guidelines for charge extraction rate engineering in nanocrystal-based devices.
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