物理化学学报Issue(1)：145-152,8.DOI:10.3866/PKU.WHXB201410241
Pd/Co双金属纳米颗粒的制备及催化制氢性能
Preparation of Pd/Co Bimetallic Nanoparticles and Their Catalytic Activity for Hydrogen Generation
摘要
Abstract
Reported here is a facile route for the synthesis of polyvinyl pyrrolidone (PVP)-stabilized Pd/Co bimetallic nanoparticles via a chemical co-reduction process. The effects of molar ratio of PVP and reducing reagent (NaBH4) to the total metal ions, and metal ion concentration and composition on the catalytic activity for hydrogen generation from NaBH4 over Pd/Co bimetal ic nanoparticles (BNPs) were studied. The transmission electron microscopy (TEM) results indicated that the prepared Pd/Co bimetallic nanoparticles, which had an average size of 1.5-2.8 nm, showed much higher catalytic activity than Pd and Co monometal ic nanoparticles (MNPs). The highest catalytic activity of al the prepared bimetallic nanoparticles was 15570 mol∙mol-1∙h-1 (the activity was normalized by the content of Pd in the BNPs), which was achieved with Pd/Co theoretical atom ratio of 1/9. The higher catalytic activity of the Pd/Co BNPs compared with the corresponding MNPs was ascribed to electronic charge transfer effects; this hypothesis was validated using density functional theory (DFT) calculations, which showed that the Pd atoms were indeed negatively charged, while the Co atoms were positively charged because of electron donation from the Co atoms to the Pd atoms. The positively charged Co atoms and negatively charged Pd atoms acted as catalytic active sites for the hydrolysis reaction of the alkaline NaBH4 solution. Good catalytic stability was observed with the existing high catalytic activity, even after five runs of evaluating the catalytic activity. Moreover, no clear agglomeration was observed in the nanoparticle catalyst used. The corresponding apparent activation energy was determined as 54 kJ∙mol-1, based on the kinetic study of the hydrogen generation achieved via the NaBH4 hydrolysis over the PVP-protected Pd10Co90 bimetal ic nanoparticles.关键词
Pd/Co/双金属纳米颗粒/NaBH4/催化制氢Key words
Pd/Co/Bimetal nanoparticle/NaBH4/Catalytic hydrogen generation分类
化学化工引用本文复制引用
赵万国,苏丽,周振宁,张海军,鲁礼林,张少伟..Pd/Co双金属纳米颗粒的制备及催化制氢性能[J].物理化学学报,2015,(1):145-152,8.基金项目
The project was supported by the National Natural Science Foundation of China (51272188,51472184,51472185), National Key Basic Research Program of China (973)(2014CB660802), Natural Science Foundation of Hubei Province, China (2013CFA086), and Foreign Cooperation Projects in Science and Technology of Hubei Province, China (2013BHE002).国家自然科学基金(51272188,51472184,51472185)面上项目,国家重点基础研究发展规划项目(973)(2014CB660802),湖北省自然科学基金重点项目(2013CFA086)及湖北省科技支撑计划对外科技合作项目(2013BHE002)资助 （51272188,51472184,51472185）
