Chemiluminescence (CL) is regarded as a better method for the detection of reactive oxygen species (ROS). However, the weak CL intensity prevents its further application. Many nanomaterials have been developed to enhance CL intensity, and mixed-ligand MOFs incorporating additional metals or organic ligands exhibit high efficiency in catalyzing. In this work, one kind of bimetallic mixed-ligand metal–organic framework (Ni-Co m-MOF) was synthesized using solvothermal methods. The material was morphologically characterized and demonstrated to be a dense and spherical flower-like structure. The addition of Ni-Co m-MOFs significantly enhanced the CL intensity of the luminol-H₂O₂ system by nearly 2,000-fold. The enhancement was found through further research as hydrogen peroxide was catalyzed to create hydroxyl radicals, etc., which reacted more easily with luminol. Herein, significant enhancement of the CL system by Ni-Co m-MOFs was identified, which provides ideas for improving the sensitivity and signal-to-noise ratio development of CL detectors.

The cobalt metal–organic framework (Co-MOF) is a kind of crystalline porous material within a periodic network structure, which is formed via the self-assembly of a Co metal center and a bridged organic ligand. In this paper, a Co-MOF was facilely synthesized via an ultrasonic method and applied to enhance the chemiluminescence (CL) emission of the NaIO₄-H₂O₂ system. The synthesized Co-MOF was nanosheet-like in nature and stacked in 2–3-micrometer flower shapes. Compared to the NaIO₄-H₂O₂ system without a Co-MOF, the CL intensity of the Co-MOF-NaIO₄-H₂O₂ system was enhanced about 70 times. This CL mechanism was determined to be a result of the synergistic effects of chemiluminescence resonance energy transfer (CRET) and electron–hole annihilation (EHA). The Co-MOF not only acted as a catalyst to accelerate the generation of reactive oxygen species in the CL reaction, but also worked as an emitter to further enhance the CL. Based on the Co-MOF-NaIO₄-H₂O₂ system, a highly sensitive CL analysis method was established for pyrogallol (PG) detection. Addition of PG into the CL system generated ¹O₂*, which could transfer energy to the Co-MOF and further enhance the CL response. The enhanced CL was linear with the PG concentration. The CL analysis method exhibited a linear range of 1 × 10⁻⁴ M to 1 × 10⁻⁷ M, as well as having a linear correlation coefficient of 0.9995 and a limit of detection of (S/N = 3) of 34 nM.

Bismuth oxyiodide and attapulgite have proven to be potential materials for the removal of emerging contaminants in wastewater.