A bifunctional nanocrystal surface: Integration of slow release of copper cations and providing active catalytical sites

Abstract

Nanoparticles represent an interesting platform that demonstrates properties absent from bulk materials. Although the employment of nanoparticles for environmental remediation has attracted tremendous attentions in both scientific research and industrial applications, there is still a huge gap between the clear mechanism understandings and their deliverable activities due to the complex reaction kinetics. Herein, we report the synthesis of high-quality, monodispersed Cu₇S₄ nanoparticles as a model nano system to investigate the degradation mechanism of organic pollutants. The morphology, chemical composition and atomic structure of the as-prepared Cu₇S₄ have been characterized by Transmission Electron Microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray powder diffractometer (XRPD) and Fourier transform infrared spectra (FT-IR). In addition, it is revealed that the Cu₇S₄ particles can effectively degrade organic pollutants, like Orange I and Orange II through a slow and controllable release of Cu cations process coupled with surface catalysis. The detailed study shows that the small amounts of released Cu cations from Cu₇S₄ nanoparticles are first coordinated with the organic pollutants and the resultant complexes are then degraded on the surface of nanoparticles in the presence of H₂O₂.