Pyramidal CdSe NCs self-assembled on highly oriented pyrolytic graphite (HOPG) substrates were characterized, both by STM and synchrotron XPS measurements, upon annealing treatments at different temperatures. By STM, shape modifications at different temperatures was observed. In particular the NCs experience a shape relaxation via an intra-particle ripening or physical coagulation after exposing the sample at 200°C, while a mass transfer via inter-particle ripening (Ostwald ripening) is activated at 400°C. Synchrotron XPS data allow establishing a clear differentiation between the desorption behavior of long octadecylphosphonic acid-related ligands and short chloride ionic ligands.

B.H.J. thanks for funding under the frame of the following projects: S2013/MIT‐2740 from Comunidad de Madrid, FIS2012‐33011, FIS2015‐67367‐C2‐1‐P, and MAT2013‐47395‐C4‐3‐R, from the Spanish Ministry of Economy and Competitiveness. R.O. thanks for FIS2012‐33011 and FIS2015‐67367‐C2‐1‐P.

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