Synthesis of a stable iron()-organic framework for a visible light induced simultaneous photocatalytic reduction of Cr() and the degradation of organic dyes in water

• Published in: New journal of chemistry Vol. 45; no. 3; pp. 1346 - 13414
• Main Authors: Xie, A-Di, Hu, Ming-Gai, Luo, Yu-Hui, Zhu, Xiang-Gui, Wang, Zhi-Hui, Geng, Wu-Yue, Zhang, Hao, Zhang, Dong-En, Zhang, Hong
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 14.08.2021
• Subjects: Catalytic activity; Chromates; Crystallography; Degradation; Dimethylformamide; Dyes; Iron; Lanthanum; Metal-organic frameworks; Modulators; Molecular orbitals; Oxidation; Photocatalysis; Reduction; Single crystals; Synergistic effect; Water pollution
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d1nj01643a

In this work, a highly stable Fe-MOF, namely [Fe 2 (OH) 2 (BPTC)]·2DMF·2H 2 O ( JOU-22 , H 4 BPTC = biphenyl-3,3′,4,4′-tetracarboxylic acid, DMF = N , N -dimethylformamide), was solvothermally synthesized using lanthanum nitrate and HF as modulators. Single-crystal diffraction shows that JOU-22 reveals a 3D microporous framework based on Fe-O chains. Due to its high chemical stability, suitable band gap (2.1 eV), and appropriate HOMO (−0.21 V) and LUMO (1.89 V) energy, JOU-22 shows efficient visible-light induced photocatalytic activity for Cr( vi ) reduction and dye degradation. JOU-22 can also be used for the degradation of organic dyes, including MB, MO, BG and RhB. Fascinatingly, in the mixed system with the co-existence of dichromate anions and MB, the degradation rate of both Cr( vi ) and MB increased significantly due to the synergistic effect between the photocatalytic reduction and oxidation process. This work not only provides a new clue for the preparation of large-size Fe-MOF single crystals, but also enriches the application of Fe-MOFs in the treatment of water pollution. A stable microporous Fe-MOF was synthesized as single-crystals and was applied as a bifunctional catalyst for the photocatalytic Cr( vi ) reduction and organic dyes degradation.