Synthesis and Characterization of Polypyrrole−Palladium Nanocomposite-Coated Latex Particles and Their Use as a Catalyst for Suzuki Coupling Reaction in Aqueous Media

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• 作者：Syuji Fujii ; Soichiro Matsuzawa ; Yoshinobu Nakamura ; Atsushi Ohtaka ; Takuto Teratani ; Kensuke Akamatsu ; Takaaki Tsuruoka ; Hidemi Nawafune
• 刊名：Langmuir
• 出版年：2010
• 出版时间：May 4, 2010
• 年：2010
• 卷：26
• 期：9
• 页码：6230-6239
• 全文大小：1127K
• 年卷期：v.26,no.9(May 4, 2010)
• ISSN：1520-5827

文摘

Polypyrrole−palladium (PPy−Pd) nanocomposite was deposited in situ from aqueous solution onto micrometer-sized polystyrene (PS) latex particles. The PS seed particles and resulting composite particles were extensively characterized with respect to particle size and size distribution, morphology, surface/bulk chemical compositions, and conductivity. PPy−Pd nanocomposite loading onto the PS seed latex particles was systematically controlled over a wide range (10−60 wt %) by changing the weight ratio of the PS latex and PPy−Pd nanocomposite. Pd loading was also controlled between 6 and 33 wt %. The conductivity of pressed pellets increased with the PPy−Pd nanocomposite loading and four-point probe measurements indicated conductivities ranging from 3.0 × 10⁻¹ to 7.9 × 10⁻⁶ S cm⁻¹. Hollow capsule and broken egg-shell morphologies were observed by scanning/transmission electron microscopy after extraction of the PS component from the composite particles, which confirmed a PS core and PPy−Pd nanocomposite shell morphology. X-ray diffraction confirmed that the production of elemental Pd and X-ray photoelectron spectroscopy indicated the existence of elemental Pd on the surface of the composite particles. Transmission electron microscopy confirmed that nanometer-sized Pd particles were distributed in the shell. The nanocomposite particles functioned as an efficient catalyst for Suzuki-type coupling reactions in aqueous media for the formation of carbon−carbon bonds.