Controllable self-assembly of CdTe/poly(N-isopropylacrylamide-acrylic acid) microgels in response to pH stimuli.

The self-assembly of hybrid CdTe/poly(N-isopropylacrylamide-acrylic acid) [poly(NIPAM-AAc)] microgels was tunable in response to pH stimuli. The pH-dependent swelling behavior of the polymer microgels played an important role in the self-assembly processes. At pH 3.73, the fractal and dendritic patterns of CdTe/poly(NIPAM-AAc) were fabricated on a large scale, in which the dipole moment of CdTe provided a significant driving force. At pH 11.28, the microgels aggregated and amalgamated to form a porous film and phase separation occurred between the CdTe nanocrystals and poly(NIPAM-AAc). The combination of the physical and chemical properties of inorganic CdTe nanocrystals with those of organic smart polymers provides a new opportunity for controllable self-assembly.