Synthesis and superior SERS performance of porous octahedron Cu2O with oxygen vacancy derived from MOFs

Fabricate surface-enhanced Raman scattering (SERS) substrate with low cost and high performance through simple method is a challenge and worthy of work. Herein, an excellent Cu2O SERS substrate with porous octahedron structure was synthesized by brief calcining Cu-MOFs in Ar, air and H2/Ar gas environment at 350 °C successively. The as-obtained octahedral Cu2O was utilized as SERS substrate to measure dye molecules and organic pollutants, which exhibited splendid sensitivity for the detection of methylene blue and 4-mercaptopyridine (4-MPY) with the ultralow limit of 5 × 10–9 M and 5 × 10–10 M, respectively. The maximum relative standard deviation for detection of 4-MPY is as low as 12.3%, which is less than limiting step in quantitative SERS (15.0%). The above excellent results are due to outstanding synergistic effect of electromagnetic enhancement of oxygen vacancy on the Cu2O surface and chemical enhancement of the Cu–S bonds formation. The fabricated Cu2O possesses superior sensitivity, selectivity and reproducibility for SERS detection of probe molecules with sulfhydryl groups and may be a prospect candidate in the practical application. An excellent Cu2O SERS substrate with porous octahedron structure was synthesized by simple calcining Cu-MOFs in Ar, air and H2/Ar gas environment at 350 °C successively. The as-prepared Cu2O play significant roles in the enhancement of SERS signals for rich-thiol detection due to outstanding synergistic effect of electromagnetic enhancement of oxygen vacancy on the Cu2O surface and chemical enhancement of the Cu-S bonds formation. The detection limit of 4-Mercaptopyridine (4-MPY) can be as low as 5×10–10 M. The porous octahedral Cu2O will have potential applications in SERS detection as the substrate.