In this work, a highly stable Fe-MOF, namely [Fe₂(OH)₂(BPTC)]·2DMF·2H₂O (JOU-22, H₄BPTC = 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.

In this work, γ -Fe ₂ O ₃ /CNTs composite was facile synthesized by simple hydrothermal method and hydrazine hydrate treatment at low temperature (CNTs = carbon nanotubes). The result of VSM shows that the saturation magnetization of Fe ₂ O ₃ /CNTs composites increase from 0 to 1.29 emu g ⁻¹ after hydrazine hydrate treatment, indicating that the Fe ₂ O ₃ in the composite transforms from α phase to γ phase. Moreover, the electrochemical properties of both α -Fe ₂ O ₃ /CNTs and γ -Fe ₂ O ₃ /CNTs was studied. Compared with α -Fe ₂ O ₃ /CNTs, γ -Fe ₂ O ₃ /CNTs shows enhanced electrochemical performance toward paracetamol determination. Under optimum condition, the γ -Fe ₂ O ₃ /CNTs modified electrode exhibits two linear ranges of 2.5 μ M−385 μ M and 593 μ M−1550 μ M and a low detection limit of 0.046 μ M. In addition, the constructed sensor can be successfully utilized for detecting paracetamol in different water bodies. This work provides a new clue for the design and construction of excellent electrochemical sensor for paracetamol determination.

A flower-like CePO ₄ with a hierarchical structure was hydrothermally prepared for electrochemical sensing of dopamine, uric acid and acetaminophen.