tailieunhanh - Báo cáo hóa học: " Polymer-stabilized palladium nanoparticles for catalytic membranes: ad hoc polymer fabrication"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Polymer-stabilized palladium nanoparticles for catalytic membranes: ad hoc polymer fabrication | Domènech et al. Nanoscale Research Letters 2011 6 406 http content 6 1 406 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Polymer-stabilized palladium nanoparticles for catalytic membranes ad hoc polymer fabrication Berta Domènech1 Maria Munoz1 Dmitri N Muraviev1 and Jorge Macanás2 Abstract Metal nanoparticles are known as highly effective catalysts although their immobilization on solid supports is frequently required to prevent aggregation and to facilitate the catalyst application recovery and reuse. This paper reports the intermatrix synthesis of Pd0 nanoparticles in sulfonated polyethersulfone with Cardo group membranes and their use as nanocomposite catalytic membrane reactors. The synthesized polymer and the corresponding nanocomposite were characterized by spectroscopic and microscopic techniques. The catalytic efficiency of catalytic membranes was evaluated by following the reduction of p-nitrophenol in the presence of NaBH4. Introduction The unusual physical chemical and catalytic properties of metal colloids better known in nowadays as metal nanoparticles MNPs have attracted increasing interest of scientists and technologists during the last decade 1 . A characteristic high percentage of surface atoms and the associated quantum effects make MNPs efficient and selective catalysts for several types of catalytic reactions 2 3 . However for most practical catalytic applications MNPs must be immobilized on solid supports to prevent their aggregation and to facilitate the catalyst recovery 4 . In this sense encapsulation of MNPs in polymers seems advantageous because in addition to stabilizing and protecting effects towards MNPs polymers offer unique possibilities for enhancing the access of reactants to the catalytic sites 5 . The in situ synthesis of MNPs into a polymeric membrane matrix permits to combine catalysis and membrane processes which may result in process intensification 6 7 destruction and .