摘要
以胆碱作为催化剂和还原剂,催化正硅酸四乙酯(TEOS)的水解/缩合反应并还原四氯金酸(HAuCl4),经一步协同反应过程制备了金/介孔二氧化硅复合粒子.通过透射电子显微镜和氮气吸附-脱附表征发现,加入胆碱后随着预处理时间由4 min分别延迟到8和15 min,复合粒子的二氧化硅壳层厚度由30 nm递减到20和8 nm;而随着反应介质中十六烷基三甲基溴化铵(CTAB)的浓度从2.0 mmol/L升高至8.0 mmol/L,二氧化硅的介孔孔径由2.0 nm增大至2.8 nm.实验中还发现,随着反应介质中水与乙醇的体积比由15∶1降低至13∶3,制得的复合粒子中金核数量增多,从单核包覆转变为多核包覆,且催化性能评价结果显示多核包覆的复合粒子具有更高的催化活性.
In this work,choline was employed as both a catalyst and a reducing agent to catalyze the hydrolysis/condensation of tetraethyl orthosilicate and reduce chloroauric acid tetrahydrate.Through a one-step concerted reaction process,successfully prepared Au/mesoporous silica composite particles.Transmission electron microscopy(TEM)and nitrogen desorption characterization revealed that thickness of the mesoporous shell increased from 30 nm to 20 and 8 nm when the pre-treatment time after the addition of choline was delayed from 4 min to 8 and 15 min,respectively.Additionally,when the concentration of cetyltrimethylammonium bromide in the reaction medium increased from 2.0 mmol/L to 8.0 mmol/L,mesoporous pore diameter of the silica shell increased from 2.0 nm to 2.8 nm.Finally,as the volume ratio of water to ethanol decreased from 15∶1 to 13∶3,number of the Au particles encapsulated within the mesoporous silica shells could be further adjusted,transitioning from single-core to multi-core encapsulation,and the catalytic results showed that the multi-core encapsulated Au/mesoporous silica composite particles exhibited higher catalytic activity.
作者
韩延东
杨文胜
HAN Yandong;YANG Wensheng(Engineering Research Center for Nanomaterials,Henan University,Kaifeng 475000,China;State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,College of Chemistry,Jilin University,Changchun 130012,China)
出处
《高等学校化学学报》
北大核心
2026年第1期214-221,共8页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21773089)
河南省科技攻关项目(批准号:242102230100)
河南省高等学校重点科研项目(批准号:24B150005)资助。
关键词
介孔二氧化硅
金粒子
复合粒子
催化性能
Mesoporous silica
Au particles
Composite particles
Catalytic performance
