Preparation of polymer-coated Pd nanoparticles on
APS-functionalized SiO2 particles
were obtained in the region of 400–4000 cm-1 by using a Bruker
Tensor 27 spectrometer. The contents of Pd(0) in catalyst A,
B and C were 0.47%, 0.35% and 0.28%, respectively, which
was determined by inductively coupled plasma optical emission
spectroscopy (ICP-AES, Vista-MPX).
The dark brown Pd(0)-SiO2 particles (0.3 g) were ultrasonically
dispersed with 35 mL of water in a 250 mL round-bottomed
flask equipped with a condenser. Allylamine (AA, 0.25 mL) and
poly(N-vinyl pyrrolidone) (PVP, 0.5 g) were added into the flask
and agitated with a magnetic stirrer at room temperature for
1 hour. Then, 0.25 g of sodium styrene sulfonate (NaSS), 0.15 g
of potassium persulfate (KPS) and 40 mL of water were added
into the flask and allowed to mix for 30 min. 2 mL of styrene (St)
and 0.2 mL of divinylbenzene (DVB) were then added. Finally,
the polymerization was carried out in a nitrogen atmosphere
under stirring at 80 ◦C for 12 hours. The resulting polystyrene-
coatedPd(0) nanoparticles on APS-functionalized SiO2 particles
were centrifugally separated from the suspension, ultrasonically
washed three times with water and twice with ethanol, and dried
under vacuum at 60 ◦C for 24 hours.
Acknowledgements
The authors are very grateful to the National Natural Science
Foundation of China (20773144) and National Key Basic
Research Project of China (2006CB202504).
Notes and references
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Thermogravimetric analysis (TGA) was performed using a
Perkin-Elmer 7 Series Thermal Analysis System. Dried samples
◦
◦
were heated to 750 C in air at a heating rate of 10 C min-1,
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