Sol–gel process of carbon-supported nickel nanoparticles using different solvents and protecting atmospheres

Carbon-supported nickel nanoparticles have been prepared by a sol–gel process under N2 or H2 atmospheres using different solvents such as distilled water, ethanol, acetone and 1-propanol. In the aqueous sol–gel process, nickel nanoparticles with pure face-centered-cubic (fcc) phase can be obtained under N2 atmosphere by using nickel nitrate, tartaric acid and sodium dodecyl sulfonate. When organic solvents are applied, nickel (Π) acetylacetone is required in order to obtain nickel nanoparticles with pure fcc phase under N2 atmosphere. When the protecting atmosphere is H2, nickel nitrate can be used to obtain nickel particles with pure fcc phase. Nickel nanoparticles with grain sizes of 4–6 nm in diameter can be prepared by using nickel (Π) acetylacetone [Ni(acac)2], citric acid and hexadecylamine with solvent being acetone. 1-propanol is also effective in the preparation of nickel nanoparticles in this sol–gel process. We suggest that this sol–gel may be used for other metallic nanocrystals.