A stable and plug-and-play aluminium/titanium dioxide/metal-organic framework/silver composite sheet for sensitive Raman detection and photocatalytic removal of 4-aminothiophenol.

The sensitive detection and rapid removal of 4-aminothiophenol (4-ATP, a poisonous pesticide) demand special design to potential substrates. Herein, a metal-organic framework (ZIF-8) and Ag nanoparticles were fabricated one by one on the TiO2 coated Al sheet, and thus the Al-TiO2-ZIF-8-Ag sheet with sandwich structure was successfully synthesized. The cost-effective Al-TiO2-ZIF-8-Ag sheet (3.7 wt% Ag) possessed a low detection concentration of 1 × 10-9 M towards 4-ATP, and surface-enhanced Raman scattering (SERS) analytical enhanced factor (AEF) of the Al-TiO2-ZIF-8-Ag was 2.6 × 106, which was higher than other similar substrates. Furthermore, 4-ATP can be selectively and repeatedly detected on the Al-TiO2-ZIF-8-Ag even through it was in real samples. It indicated that the Al-TiO2-ZIF-8-Ag was a very active and stable SERS materials for the monitoring of 4-ATP. Importantly, the substrate exhibited faster and more efficient photocatalytic activity for 4-ATP degradation. The SERS and photocatalytic mechanisms of 4-ATP on the Al-TiO2-ZIF-8-Ag substrate were proposed. The cost-effective Al-TiO2-ZIF-8-Ag sheet with double function is plug-and-play, and could be used in the detection and treatment of pollutants in wastewater.