Simple synthesis of high-quality CdTe QDs in spherical polyelectrolyte brushes with stable and reversible photoluminescence

Abstract

A facile method of high-quality CdTe quantum dots (QDs) synthesis in spherical polyelectrolyte brushes (SPBs) was reported in this work. The size of CdTe QDs, with emission color from green to red, could be tuned by adjusting the duration of nucleation, feed ratio of reductants (NaBH 4 / N 2 H 4 ), and pH of precursor (SPB solution). Short duration of nucleation and low ratio of NaBH 4 /N 2 H 4 could promote the growth rate of QDs to form big-sized CdTe QDs. The pH of SPB solution, in the range of 7-9, was optimal condition for formation of high-quality QDs. The SPB@CdTe exhibited high photochemical stability as the pH of mixture was above 10, which could be stored in the visible light for several months without aggregation and optical deterioration. The photoluminescence emission of SPB@CdTe could be reversibly quenched and restored with shrinkage and swollen shell if employed pH as a regulator.

Synthesis, characterization and cytotoxicity of polyethylene glycol-encapsulated CdTe quantum dots

“…Nevertheless, they suffer from certain limitations. First, they possess lower quantum yields compared to those prepared in organic media [12]. Second, they tend to aggregate with time due to the weakly bound thiol ligands.…”