Room-temperature syntheses of CdS nanocrystals templated by triblock copolymer in aqueous solution under air condition

CdS nanocrystals with size of 5.0–10.0 nm were synthesized from air-insensitive inorganic precursors of CdCl2 · 2.5H2O and Na2S · 9H2O at room temperature in both acidic and basic aqueous solutions under air condition, using the nonionic pluronic amphiphilic triblock copolymer of P123 (H–(–OCH2CH2)20[–OCH(CH3)–CH2]70–(–OCH2CH2)20–OH, as well as (EO)20–(PO)70–(EO)20) as the template and structure-directing agent. The X-ray powder diffraction patterns index to the cubic crystal structure of sphalerite for CdS nanocrystals synthesized. UV–Vis absorption spectra indicate the obvious blue shift for the band gap of CdS nanocrystals prepared in the water-rich P123 aqueous solution.