Ultraweak chemiluminescence enhanced on the surface of lanthanide metal-organic framework nanosheets synthesized by ultrasonic wave

In this paper, lanthanide metal-organic frameworks (Ln-MOFs, Ln = Ce, Gd, Ho) were facilely synthesized by ultrasonic method and applied in enhancing chemiluminescence (CL) emission of NaIO4-H2O2 system. The synthesized Ln-MOFs were characterized to be nanosheet-like shapes. Comparing with the NaIO4-H2O2 system without Ln-MOFs, the CL intensities of Ln-MOFs-NaIO4-H2O2 systems were enhanced 28, 32 and 67 times by CeMOFs, Gd-MOFs and Ho-MOFs, respectively. Catalytic properties of Ln-MOFs accounted for the improved performance in CL and increased the generation of some reactive oxygen species (ROS) (.O2-, 1O2 and .OH) which induced CL enhancement. The large surface area of nanosheets and structural defects generated during the ultrasonic synthesis process could facilitate the exposure of catalytic active sites and ROS generation. This work gave insights into developing novel CL systems based on advanced materials with effective surfaces.