摘要
以氯化钯为反应原料,在HEPES溶液中采用回流法合成钯纳米颗粒,该法具有环境友好、简便的特点.运用能量分析光谱仪(EDX)、透射电镜(TEM)、高分辨透射电镜(HRTEM)和选区电子衍射(SAED)对所合成样品进行表征.考察了表面活性剂、反应时间对纳米颗粒分散性和尺寸的影响.测定了钯纳米颗粒对Suzuki反应的催化活性及重复使用效果.结果表明,所合成的钯粒径在10~13nm之间,PVP的存在可提高纳米钯的分散性、减小颗粒尺寸,过长的反应时间不利于小颗粒及分散性好的钯颗粒的形成.所合成的纳米钯在乙醇/水体系中对Suzuki反应有很好的催化活性和循环使用稳定性,催化活性显著高于商业化的钯碳催化剂,重复使用3次产率均可达90%以上.
Pd nanoparticles were facile and environmentally friendly synthesized from PdC12 in HEPES (2-[4-(2-hydroxyethyl)-l-piperazinyl-]ethanesulfonic acid) solution via refluxing method. The products were characterized by energy dispersive spectrometry (EDX), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED). The influence of surfactant and reaction time on dispersity and the size of Pd nanoparticles were investigated. The results showed that the size of Pd nanoparticles is in the range of 10 to 13 nm; the existence of PVP can increase the dispersity and reduce the size of Pd nanoparticles.Exceed reaction time is not in favor of the formation of well dispersed and small Pd nan- oparticles. The as-synthesized Pd nanoparticles exhibited high catalytic activity and reused stability toward the Suzuki reaction in the ethanol/water system. The catalytic activity of Pd nanoparticles is apparent higher than that of commercial Pd/C catalyst. The yield can arrive to more than 90% after three reused.
出处
《华中师范大学学报(自然科学版)》
CAS
北大核心
2013年第2期221-224,228,共5页
Journal of Central China Normal University:Natural Sciences
基金
教育部新世纪优秀人才支持计划(NCET-09-0136)
湖北省自然科学基金项目(2011CDB219)
湖北省教育厅重点项目(D20111510)
武汉市科技局对外科技合作与交流计划(201171034319)