银纳米颗粒掺杂的活性微孔炭球:一种高效吸附/催化去除刚果红的双功能材料

Ag Nanoparticle⁃Doped Activated Microporous Carbon Spheres:An Efficient Adsorption/Catalysis Bifunctional Material for the Removal of Congo Red

以载银纳米颗粒壳聚糖溶液为前驱体,联合喷雾干燥法、高温碳化法和KOH活化法制备出银纳米颗粒掺杂的活性微孔炭球(Ag/AMCSs)。基于一系列表征和性能研究发现,银纳米颗粒均匀分布于Ag/AMCSs结构中,Ag/AMCSs不仅表现出优异的染料吸附性能,而且可以有效催化NaBH_(4)还原刚果红(CR)的反应。此外,通过研究pH值、接触时间和染料初始浓度对Ag/AMCSs吸附性能的影响,发现Ag/AMCSs对CR的吸附过程符合准二级动力学模型和Langmuir模型,最大吸附量(q_(e))可达445 mg·g^(-1)。Ag/AMCSs催化NaBH_(4)还原CR,反应速率常数k可达0.311 min^(-1),5次循环利用后,染料催化转化率仍可高达95%。

Herein,we fabricated silver nanoparticle⁃doped activated microporous carbon spheres(Ag/AMCSs)through a combining method of spray drying,carbonization,and KOH activation by using chitosan as a precursor.Based on a series of characterization and performance studies,Ag/AMCSs are confirmed to be able to function as both an adsorbent and a catalyst for the reduction of Congo red(CR)in the presence of NaBH_(4) due to the high poros⁃ity and high dispersion of silver nanoparticles.Adsorption studies were performed by varying pH,contact time,and initial concentration,and it was found that the adsorption process could be well estimated by the pseudo⁃second⁃order kinetic plot and Langmuir models,and the maximum adsorption capacity of Ag/AMCSs was estimated as 445 mg·g^(-1).For the reduction of CR,the rate constant k was calculated up to 0.311 min^(-1),and the conversion efficiency of CR remained at 95%after 5 successive cycles.