Conventional routes for synthesizing quantum dots use a high temperature, rapid injection process that makes producing large batches of quantum dots with consistent quality a challenge. Quantum dots grow faster in hot spots within the reaction vessel and slower in the cooler portions, thus broadening the size distribution of the final product and generating undesirably broad photoluminescence emission. Combining many small batches presents its own challenges because batch to batch variations cause the emission of the combined batches to broaden significantly.
A novel process relies on a perturbed, low temperature equilibrium between quantum dot growth and dissolution. The creation of a thermodynamic equilibrium provides control over the net nanoparticle growth rate, quantum dot size, and shape. This process keeps the nanocrystal in its original solvent, allowing the nanocrystal to retain the desired characteristics of high efficiency and tunable photoluminescence emission. The process also scales up readily from small to large batch sizes without compromising quality.