Kinetic analysis of the growth behavior of perovskite CsPbBr3 nanocrystals in a microfluidic system

Understanding the growth behavior of nanoparticles and semiconductor nanocrystals under dynamic environments is of profound importance in controlling the sizes and uniformity of the prepared nanoparticles and semiconductor nanocrystals. In this work, we develop a relation between the bandgap (the photoluminescence peak wavelength) of semiconductor nanocrystals and the total flow rate for the synthesis of semiconductor nanocrystals in microfluidic systems under the framework of the quantum confinement effect without the contribution of Coulomb interaction. Using this relation, we analyze the growth behavior of CsPbBr3 nanocrystals synthesized in a microfluidic system by an antisolvent method in the temperature range of 303 to 363 K. The results demonstrate that the square of the average size of the CsPbBr3 nanocrystals is inversely proportional to the total flow rate and support the developed relation. The activation energy for the rate process controlling the growth of the CsPbBr3 nanocrystals in the microfluidic system is 2.05 kJ mol(-1). Increasing the synthesis temperature widens the size distribution of the CsPbBr3 NCs prepared in the microfluidic system. The method developed in this work provides a simple approach to use photoluminescent characteristics to in situ monitor and analyze the growth of semiconductor nanocrystals under dynamic environments.

Automated summary

In this study, the growth behavior of CsPbBr3 nanocrystals synthesized in a microfluidic system was analyzed by establishing the relation between bandgap and flow rate. The results showed that the size of the nanocrystals is inversely proportional to the flow rate, and increasing synthesis temperature leads to a wider size distribution.