Thermal Stability of Lead Sulfide Nanocrystals Synthesized through Green Chemical Route

In this research, lead sulfide (PbS) nanocrystals were synthesized via a simple, effective and green method. Then, the effects of heat-treatment at different temperatures on the PbS nanocrystals were investigated. In addition, the average crystallite size using Scherrer´s formula, and lattice constant using Bragg´s equation were calculated and compared with the standard value. The obtained results showed that an increase in the heat-treatment temperature from 250 to 450 °C brought a significant increase in the average crystallite size D of PbS nanocrystals from 13.16 nm to 32.90 nm. The thermal stability of nanocrystals determines the possibility of using these materials in devices operating under conditions above room temperature. It suggests that an increase in the thermal stability extends the temperature range of practical applications. However, an increase in the operating temperature can lead to structural and phase transformations.