Semiconductor nanocrystals (NCs) in the size range of 1–10 nm exhibit unique size-dependent photoluminescence properties, distinct from either the corresponding molecules or bulk materials, which are a result of quantum confinement effect and enormously high specific surface area [1]–[5]. Accordingly, there is much speculation about the potential use of semiconductor NCs in a vast spectrum of high-technology fields such as optics, electronics, and biomedicine. In this context, the past decade has seen a great progress in tailoring a diversity of semiconductors into nanometer-sized particles with defined but varied size, shape, and surface chemistry [6]–[9]. Once prepared, however, NCs in general have a strong tendency to agglomerate owing to the presence of a great deal of highly active surface atoms, which dramatically deteriorates their physicochemical properties. Stabilization of NCs is necessitated for both exploring their intrinsic size-related properties and exploiting their technical applicability. Up to now numerous approaches have been developed to stabilize semiconductor NCs by surface charges [6], functionalized alkanes [6]–[9], silica [10]–[13], and polymers [14]. The stability of a NC is determined by the thermodynamic balance between repulsive interactions — mainly electrostatic repulsion and steric repulsion — and attractive interactions — mainly van der Waals and hydrophobic interaction; the NC is stable when the repulsive interactions are dominant. Since the electrostatic repulsion is rather sensitive to the size of NCs and the variation of the surrounding media, steric repulsion is envisioned ideal for stabilization of NCs.