不同气体氛围下退火制备Fe_(3)O_(4)@@SiO_(2)@C/Cu纳米材料及催化性能研究

Preparation and catalytic performance of Fe 3O 4@SiO 2@C/Cu nanomaterials by annealing in different gas atmospheres

目的:研究制备一种高效稳定的磁性纳米复合材料来降解水中污染物亚甲基蓝。方法:制备的Fe_(3)O_(4)作为磁性内核,正硅酸乙酯形成二氧化硅层,甲醛提供碳源制备Fe_(3)O_(4)@SiO_(2)@RF/Cu^(2+),然后在管式炉中进行碳化并且原位还原Cu^(2+)为Cu纳米粒子制得Fe_(3)O_(4)@SiO_(2)@C/Cu x纳米催化剂。通过改变碳化的气体氛围来探究不同气体氛围下碳化得到的样品和不同催化剂投加量对催化亚甲蓝的性能影响。结果:同一样品在其他外界条件相同的情况下其催化效率随着催化剂投加量的增加而提高,N_(2)氛围下碳化得到的富含N掺杂的样品的催化效率要高于Ar氛围下碳化得到的样品。结论:实验制备的Fe_(3)O_(4)@SiO_(2)@C/Cu x复合材料表现出了优异的催化速率,并且经过N掺杂后催化速率有显著的提高,5次重复实验中,MB的降解率均在95%以上,有着很好的稳定性并且可快速回收,在废水处理领域有着广泛的应用前景。

Aims:An efficient and stable magnetic nanocomposite was prepared to degrade p-nitrophenol in water.Methods:With Fe_(3)O_(4)as the magnetic core,tetraethyl orthosilicate as the silicon source,and formaldehyde as the carbon source,Fe_(3)O_(4)@SiO_(2)@RF/Cu^(2+)was prepared.Then Fe_(3)O_(4)@SiO_(2)@C/Cu x nanocatalyst was prepared by carbonization in tube furnace and in-situ reduction of Cu^(2+)to Cu nanoparticles.By changing the gas atmosphere of carbonization,the effects of samples obtained by carbonization under different gas atmospheres and different catalyst dosage on the performance of catalytic methylene blue were investigated.Results:Under the same external conditions,the catalytic rate of the same sample increased with the increase of catalyst dosage;and the catalytic efficiency of N-doped samples obtained by carbonization in N_(2)atmosphere was higher than that of samples obtained by carbonization in Ar atmosphere.Conclusions:The Fe_(3)O_(4)@SiO_(2)@C/Cu x composite material prepared in the experiment showed excellent catalytic rate;and the catalytic rate was significantly improved after N doping.In the five repeated experiments,the degradation rate of MB was above 95%.It has good stability and can be quickly recovered and has a wide application prospect in the field of wastewater treatment.