Premium
Hydrothermal Synthesis of Platinum‐Group‐Metal Nanoparticles by Using HEPES as a Reductant and Stabilizer
Author(s) -
So ManHo,
Ho ChiMing,
Chen Rong,
Che ChiMing
Publication year - 2010
Publication title -
chemistry – an asian journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.18
H-Index - 106
eISSN - 1861-471X
pISSN - 1861-4728
DOI - 10.1002/asia.201000066
Subject(s) - hepes , platinum nanoparticles , chemistry , metal , inorganic chemistry , nanoparticle , platinum , nuclear chemistry , aqueous solution , polymer chemistry , organic chemistry , catalysis , materials science , nanotechnology , biochemistry
Platinum‐group‐metal (Ru, Os, Rh, Ir, Pd and Pt) nanoparticles are synthesized in an aqueous buffer solution of 4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) (200 m M , pH 7.4) under hydrothermal conditions (180 °C). Monodispersed (monodispersity: 11–15 %) metal nanoparticles were obtained with an average particle size of less than 5 nm (Ru: 1.8±0.2, Os: 1.6±0.2, Rh: 4.5±0.5, Ir: 2.0±0.3, Pd: 3.8±0.4, Pt: 1.9±0.2 nm). The size, monodispersity, and stability of the as‐obtained metal nanoparticles were affected by the HEPES concentration, pH of the HEPES buffer solution, and reaction temperature. HEPES with two tertiary amines (piperazine groups) and terminal hydroxyl groups can act as a reductant and stabilizer. The HEPES molecules can bind to the surface of metal nanoparticles to prevent metal nanoparticles from aggregation. These platinum‐group‐metal nanoparticles could be deposited onto the surface of graphite, which catalyzed the aerobic oxidation of alcohols to aldehydes .