Microfluidic reactor synthesis and photocatalytic behavior of Cu@Cu₂O nanocomposite

Highlights: • The Cu@Cu₂O nanocomposites were synthesized in microfluidic reactor followed by oxidation process. • The Cu@Cu₂O composite particle is on nanoscale exhibiting an open bicontinuous structure. • The amount of Cu₂O can be controlled by varying drying temperature. • The binary Cu@Cu₂O–H₂O₂ systems exhibit an excellent photocatalyst for degradation methylene blue under UV irradiation. - Abstract: The Cu@Cu₂O nanocomposites were synthesized by solution-phase synthesis of Cu nanoparticles in microfluidic reactor at room temperature, followed by controlling the oxidation process. The size, morphology, elemental compositions, and the chemical composition on the surface of Cu@Cu₂O nanocomposite were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Experimental results demonstrated that the surface of the Cu nanoparticles was oxidized to Cu₂O which serves as the shell of nanoparticle. The amount of Cu₂O can be controlled by varying the drying temperature. Additionally the binary Cu@Cu₂O nanocomposite along with H₂O₂ exhibited its potential as an excellent photocatalyst for degradation of methylene blue (MB) under UV irradiation