• Journal of Surface Science and Engineering
• /
• v.43 no.2
• /
• pp.105-110
• /
• 2010

Electroless nickel plating on porous carbon substrate for the application of MCFC electrodes was investigated. Acidic and alkaline bath were used for the electroless nickel plating. The pore sizes of carbon substrates were 16-20 ${\mu}m$ and over 20 ${\mu}m$. The carbon surface was changed from hydrophobic to hydrophilic after immersing the substrate in an ammonia solution for 40 min at $60^{\circ}C$. The contact angle of water was decreased from $85^{\circ}C$ to less than $20^{\circ}$ after ammonia pretreatment. The deposition rate in the alkaline bath was higher than that in the acidic bath. The deposition rate was increased with increasing pH in both acidic and alkaline bath. The content of phosphorous in nickel deposit was decreased with increasing pH in both acidic and alkaline bath. The contents of phosphorous is low in alkaline bath. The minimum concentration of $PdCl_2$ for the electroless nickel plating was 10 ppm in alkaline bath and 5 ppm in acidic bath. The thickness of nickel was not affected by the concentration of $PdCl_2$.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.8
• /
• pp.2711-2716
• /
• 2011

para-Substituted phenoxide derivatives of Pd(II) having an NCN pincer, Pd(NCN)($OC_6H_4$-p-X) (NCN = 2,6-$(CH_2NMe_2)_2C_6H_3$; X = $NO_2$ (1), Me (2)) were prepared by the reaction of Pd(NCN)($OSO_2CF_3$) with equi-molar amount of $NaOC_6H_4$-p-X. Treatment of Pd(NCN)($OSO_2CF_3$) with an excess amount of $NaOC_6H_4$-p-Me affords the hydrogen-bonding adduct complex 3 ($2{\cdot}HOC_6H_4$-p-Me). Complex 3 can also be obtained from benzene solution of 2 in the presence of free $HOC_6H_4$-p-Me. Complex 1 does not undergo adduct formation with $HOC_6H_4-p-NO_2$ neither from metathesis reaction of Pd(NCN)($OSO_2CF_3$) with an excess amount of $NaOC_6H_4-p-NO_2$ nor from treatment of 1 with free $HOC_6H_4-p-NO_2$. Complex 3 undergoes fast exchange of the coordinated p-cresolate with the hydrogen-bonding p-cresol. Complex 2 undergoes ${\sigma}$-ligand exchange reaction with $HOC_6H_4-p-NO_2$ to give 1. The exchange reaction, however, is irreversible as readily anticipated from their respective $pK_a$ values of the phenol derivatives. Reaction of 2 with diphenyliodium chloride quantitatively produced Pd(NCN)Cl and PhI along with liberation of O-phenylated product $PhOC_6H_4$-p-Me which was identified by GC/MS spectroscopy.