Microinjection titration synthesis of CdS nano-particles with S-type interface-phase junctions for efficient photocatalytic degradation of rhodamine B

Currently, water scarcity caused by pollution is a serious threat to human survival and development. To address this problem, impurity energy levels of-NH2 groups using CS2-storage material (CS2SM) as an S source were introduced in this study, and CdS nano-particles (NPs) with enhanced sulfur vacancies (Vs-CdS NPs) and S-type interface-phase junctions were synthesized through a simple microinjection titration strategy. Moreover, rhodamine B (Rh B) with a volume of 100 mL and a concentration of 100 mg/L could be 99.7% degraded over 60 min using 20 mg of CdS NPs at pH = 6.0, T = 28 degrees C, and 300 W xenon lamp (optical power of 150 mW) irra-diation. The high photocatalytic activity of the as-synthesized CdS NPs is owing to the intrinsic electric field, energy band bending, and Coulomb forces that occur between the hexagonal and cubic phases. In addition, the presence of Vs-CdS NPs can easily capture the photogenerated carriers of CdS NPs during recombination. Moreover, the photogenerated carriers are affected by the high and low energies between the Vs-CdS NPs, resulting in the transfer of the photogenerated carriers between the Vs-CdS NPs, which ultimately prolongs the lifetime of photogenerated carriers in the CdS NPs. Subsequently, a photocatalytic mechanism of S-type interface-phase junctions was proposed to explain the highly efficient photocatalytic activity and excellent op-toelectronic properties of CdS NPs.

Automated summary

Currently, water scarcity caused by pollution poses a serious threat to human survival and development. In this study, a new storage material and synthesis method were introduced to successfully synthesize CdS nanoparticles with enhanced photocatalytic activity. A photocatalytic mechanism was proposed to explain the high efficiency and excellent properties of the CdS nanoparticles.