论文部分内容阅读
采用浸渍法制备不同负载量NiFe_2O_4的负载型光催化剂NiFe_2O_4/g-C_3N_4,利用XRD、FT-IR、N_2-adsorption、ICP-OES、TEM及XPS等手段表征NiFe_2O_4/g-C_3N_4样品,并考察其对甲基橙的可见光催化降解性能。结果表明,与NiFe_2O_4和g-C3N4样品相比,负载型NiFe_2O_4/g-C_3N_4样品对甲基橙具有更好的光催化降解活性,且催化活性随着NiFe_2O_4负载量增大(0.5~5.0wt%)而呈现先增大再减小的趋势。NiFe_2O_4负载量2.0wt%的样品2-Ni Fe/CN在可见光照射下对浓度5 mg·L~(-1)的甲基橙表现出最好的降解活性和稳定性。这是因为能带宽度小(1.5 e V)的NiFe_2O_4与能带宽度大(2.7 e V)的g-C_3N_4形成的异质结催化剂NiFe_2O_4/g-C_3N_4,有效地促进光生载流子在二者界面快速传递和光生电子-空穴对的有效分离。
The NiFe_2O_4 / g-C_3N_4 photocatalyst with different loadings of NiFe_2O_4 was prepared by impregnation method. The samples were characterized by XRD, FT-IR, N_2-adsorption, ICP- Visible light catalytic degradation of methyl orange. The results showed that the loaded NiFe 2 O 4 / g-C 3 N 4 sample had better photocatalytic activity than methyl NiFe 2 O 4 and g-C3N 4 samples, and the catalytic activity increased with the increase of NiFe 2 O 4 loading (0.5-5.0 wt% ) Showed a trend of first increasing and then decreasing. The sample 2-Ni Fe / CN with 2.0wt% NiFe2O4 loading exhibited the best degradation activity and stability to methyl orange with the concentration of 5 mg · L -1 under visible light irradiation. This is because the heterojunction catalyst NiFe_2O_4 / g-C_3N_4 formed by NiFe_2O_4 with a small bandgap (1.5 eV) and g-C_3N_4 with a large bandgap (2.7 eV) effectively promoted the photogenerated carriers in both Rapid transfer of interfaces and efficient separation of photogenerated electron-hole pairs.