Fujii Yuki, Imagawa Kaori, Omura Taro, Suzuki Toyoko, Minami Hideto
Department of Chemical Science and Engineering, Graduated School of Engineering, Kobe University, Kobe 657-8501, Japan.
ACS Omega. 2020 Jan 24;5(4):1919-1926. doi: 10.1021/acsomega.9b03634. eCollection 2020 Feb 4.
We reported the preparation of porous cellulose particles by the solvent-releasing method, in which a solution of cellulose, dissolved in 1-butyl-3-methylimidazolium chloride and ,'-dimethylformamide, was dropped into a large amount of 1-butanol using a syringe. The obtained particles had a high specific area because of their porous structure. Herein, to functionalize the cellulose particles, carboxylate groups are introduced into their porous structure by 2,2,6,6-tetramethylpiperidine-1-oxyl-mediated oxidation and ion exchange of carboxylate groups to Ag cations is conducted. Composite cellulose/Ag particles were synthesized by the reduction reaction using the carboxylate groups as a scaffold without free silver nanoparticles in the medium. The obtained composite particles exhibited a high catalytic ability, which was evaluated by examining the reduction of 4-nitrophenol. Moreover, we determined that the catalytic efficiency was maintained for at least three cycles by immobilizing Ag on cellulose particles.
我们报道了通过溶剂释放法制备多孔纤维素颗粒的方法，即将溶解于1-丁基-3-甲基咪唑氯盐和N,N'-二甲基甲酰胺中的纤维素溶液用注射器滴入大量的1-丁醇中。由于其多孔结构，所得到的颗粒具有较高的比表面积。在此，为了使纤维素颗粒功能化，通过2,2,6,6-四甲基哌啶-1-氧基介导的氧化将羧酸根基团引入其多孔结构中，并将羧酸根基团与银阳离子进行离子交换。以羧酸根基团为支架，通过还原反应合成了复合纤维素/银颗粒，介质中不存在游离的银纳米颗粒。通过检测4-硝基苯酚的还原反应来评估所得到的复合颗粒具有较高的催化能力。此外，我们还确定通过将银固定在纤维素颗粒上，催化效率至少能保持三个循环。
