연세대학교 이과대학 화학과

일시: 2024년 11월 28일 (목) 오후 5시

장소: 과학관 B130호

초록 : Although CdS is a promising photocatalyst based on visible light, it is highly toxic. Therefore, in addition to research to improve its photocatalytic properties, attention should also be paid to its ability to be recovered, taking into account environmental aspects. One of the easiest ways to recover photocatalytic nanoparticles is to add magnetic nanoparticles to CdS to create a heterostructure. In this study, Fe₃O₄ (ferrimagnetic) and CoO (paramagnetic) NPs with different magnetic properties were combined with CdS to synthesize CdS/Fe₃O₄ and CdS/CoO heterostructure systems, and both the photocatalytic degradation efficiency and the recovery efficiency of the NPs were measured. The two heterostructures showed significant improvement in photocatalytic properties compared with CdS, but showed distinct differences in recovery efficiency due to their magnetic properties. The CdS/Fe₃O₄ heterostructure system was found to be the most suitable system for the purpose of this study, as its photocatalytic properties were enhanced compared to CdS and its magnetic properties did not show a significant degradation compared to Fe₃O₄ . For CdS/Fe₃O₄ heterostructure system, the conversion of 2,5-hydroxymethylfurfural to 5-formylfuran-2-carboxylic acid was increased by ~22% compared to CdS. Furthermore, the magnetic properties were only degraded by ~6.8% compared to Fe₃O₄ NPs, confirming their applicability. Visible light photocatalytic conversion experiments were performed to measure the photocatalytic properties of the two heterostructures, and in situ X-ray photoelectron spectroscopy was used to determine the changes in electronic structure under optimized conditions.