Synthesis and characterization of CBD-CdS nanospheres

Cadmium sulfide (CdS) nanospheres were successfully synthesized by chemical bath deposition (CBD) in the systems cadmium nitride tetrahydrate (Cd(NO₃)₂.4H₂O) - thiourea (NH₂CSNH₂) - complexing agent - pH buffer. An L₉ Taguchi experimental design was used with the purpose of determines the processing conditions to promote CdS nanospheres formation. For that reason, the processing parameters were varied at three levels, as follows: complexing agent (without complexing agent, glycine (NH₂CH₂COOH) and sodium citrate (Na₃C₆H₅O₇)), pH buffer (4 mL of borate, pH 11; 2 mL of ammonium hydroxide/ ammonium chloride, pH 10; and 2 mL of borate/pH 11), temperature (323.15, 338.15, and 353.15 K) and time (20, 30, and 40 minutes). Microstructural study was performed by SEM/EDS, XRD and laser particle size analyzer. According to characterization results, analysis of variance (ANOVA) and main effects, the processing conditions for CBD-CdS nanospheres synthesis are: cadmium nitride (Cd(NO₃)₂.4H₂O), thiourea (NH₂CSNH₂), glycine as complexing agent, and borate as buffer (2 mL) at 338.15 K for 40 minutes.