CuFe2O4/纳米纤维素磁性复合材料的制备及催化性能

采用简单易行的一锅溶剂热法原位合成CuFe₂O₄/纳米纤维素（CuFe₂O₄/CNC）磁性复合材料，并研究CuFe₂O₄/CMC磁性复合材料催化剂在NaBH₄作用下催化还原4-硝基酚（4-NP）性能。结果表明：所制备的CuFe₂O₄/CNC磁性复合材料为单一尖晶石结构，具有超顺磁性，纳米颗粒尺寸约为10 nm，其饱和磁化强度为33.15 emu·g^-1。与CuFe₂O₄纳米颗粒相比，CuFe₂O₄/CNC磁性复合材料的比表面积提高到89.9 m²·g^-1（CuFe₂O₄纳米颗粒的比表面积为53.9 m²·g^-1）。CNC有助于改善CuFe₂O₄的单分散性，且对4-NP的吸附作用能加快反应的传质速率。将CuFe₂O₄/CNC磁性复合材料用于催化还原4-NP，反应符合一级动力学特征；当CNC的添加量为0.2 g时，可以将4-NP（100 μL，0.005 mol·L^-1）溶液在25 s催化还原完全，表现出优异的反应活性。催化剂循环使用5次后，对4-NP的转化率仍能保持90%以上。

Synthesis and catalysis properties of magnetic CuFe2O4/cellulose composites

Magnetic CuFe₂O₄/cellulose nano crystals (CuFe₂O₄/CNC) composite was presented via a facile one-step solvothermal method. The catalytic reduction of 4-nitrophenol (4-NP) was tested with the addition of NaBH₄. The results show that the prepared superparamagnetic CuFe₂O₄/CNC composite is a cubic spinel crystal structure with the nano particle size of 10 nm, presenting the saturation magnetization of 33.15 emu·g^-1. Compared with CuFe₂O₄ nano particles, the CuFe₂O₄/CNC composite shows a higher specific surface area of 89.9 m²·g^-1 (the specific surface area of CuFe₂O₄ nano particles is 53.9 m²·g^-1). The CNC helps to improve the monodispersity of CuFe₂O₄ nano particles and absorbs 4-NP to facilitate the mass transfer rate positively. The CuFe₂O₄/CNC composite is conducted to catalytic reduction of 4-NP. The dynamic kinetics of the catalytic reduction is the first order process. When 0.2 g CNC is added, CuFe₂O₄/CNC composite can catalyze the reduction of 4-NP (100 μL, 0.005 mol·L^-1) within 25 s, showing a high catalytic activity. The conversion rate of 4-NP can still reach 90% even after 5 cycles.