The multicomponent heterostructure flower spherical Ce-MOF/CdIn2S4/CdS for ciprofloxacin photodegradation via effective electron transfer

Abstract

The charge separation efficiency and photocatalytic performance can be effectively improved by constructing heterojunction between an inorganic semiconductor and a metal-organic framework. Consequently, in this paper, Ce-MOF synthesized in a water bath was used as the precursor, and Ce-MOF/CdIn₂S₄/CdS multicomponent heterojunction composites were successfully prepared by microwave-assisted hydrothermal method. The rod-like Ce-MOF interspersed with CdIn₂S₄/CdS composite material with spherical morphology formed by CdIn₂S₄ nanosheets loaded around the center spherical CdS. Meanwhile, in ciprofloxacin (CIP) degradation experiments, the photocatalytic efficiency of 10 % Ce-MOF/CdIn₂S₄/CdS for CIP reached 76.7 % within 120 min of full-spectrum light irradiation; the corresponding kinetic rate constant was 0.0089 min⁻¹. Its value was 12.7, 2.6, 2.6, 1.5, 1.4, 1.7, and 1.2 times higher than those of Ce-MOF, CdIn₂S₄, CdS, CdIn₂S₄/CdS, 5 % Ce-MOF/CdIn₂S₄/CdS, 20 % Ce-MOF/CdIn₂S₄/CdS, and 40 % Ce-MOF/CdIn₂S₄/CdS, respectively. The improved photocatalytic activity of 10 % Ce-MOF/CdIn₂S₄/CdS composite toward CIP is attributed to the synergistic effect between the unique Ce-MOF structure and multicomponent heterojunction. It not only promotes the tunable bandgap characteristics of the composite but also greatly prolongs the lifetime of photogenerated electrons (e⁻) and holes (h⁺), thereby improving the utilization efficiency of photogenerated carriers and enhancing the electron transfer efficiency at the interface. This speculation can be directly confirmed by photoelectric chemical experiments. The multicomponent heterojunction existed in photocatalyst system can be speculated by combined with active species capture experiment and energy band structure, which has a prominent application prospect in the treatment of antibiotic wastewater.