Facet‐Dependent On‐Surface Reactions in the Growth of CdSe Nanoplatelets

Abstract

Facet‐dependent on‐surface reactions are systematically studied on zinc‐blende CdSe nanoplatelets with atomically‐flat {001} basal facets and small yet non‐polar side facets. The on‐surface half‐reactions between the surface Se sites and Cd carboxylates in the solution is qualitatively the same as those on the spheroidal counterparts. Conversely, the on‐surface half‐reactions between the surface Cd sites and the activated Se precursors in solution shows strong facet‐dependence, which includes three distinguishable stages. In the first stage, the Se precursors are adsorbed onto the small and non‐polar side facets of the nanoplatelets. The second stage is initiated by the adsorbed Se precursors at the side‐basal plane edges and proceeds from the edges to the center of basal planes in a quasi‐zeroth order kinetics. The third stage would start to destroy the nanoplatelets, including creating a hole in the middle and building thick edges.