Two-minute synthesis of PbS nanocubes with high yield and good dispersibility at room temperature

A novel water/glycerol/polyvinylpyrrolidone (PVP) ternary system is developed to realize the successful growth of PbS nanocubes with a narrow size distribution and sharp facets and edges using a one-step synthesis at room temperature for the first time. The synthesis is very fast, high yield, environment-friendly, and low cost. The product possesses uniform dimensionality, high crystallinity and better dispersibility. After dispersing the nanocubes in water or ethanol, the as-formed colloidal suspensions can maintain excellent stability for more than one year under ambient conditions. Uniform silica layers were successfully coated onto the nanocubes via a modified Stöber method to enhance their performance for promising applications. Moreover, by soaking the as-prepared PbS/SiO(2) core-shell nanocubes in hydrochloric acid aqueous solution, well-resolved cubic SiO(2) nanoboxes were obtained. The formation mechanism and the reason for the better dispersibility and excellent stability of the as-obtained nanocubes are also discussed rationally.