The radical intermediate, which is produced in the process of electroless nickel plating, was detected in the presence of water-soluble trap α-4-pyridy1-N-tert-buty1 nitrone（POBN） or α-phenyl-tert-buty1 nitrone（...The radical intermediate, which is produced in the process of electroless nickel plating, was detected in the presence of water-soluble trap α-4-pyridy1-N-tert-buty1 nitrone（POBN） or α-phenyl-tert-buty1 nitrone（PBN） by electron spin resonance（ESR） spectroscopy. The results obtained indicated that a 16-line（g=2.006 1, aβ<sub>C—H=1.98×10-4 T, aγ<sub>P—H=3.32×10-4 T, aN=aP=15.93×10-4 T） or a 18-line （g=2.004 9, aβ<sub>C—H=aγ<sub>P—H=2.38×10-4 T, aP=17.72×10-4 T, aN=16.20×10-4 T） ESR spectrum was observed in the process of electroless nickel plating when spin trap PBN or POBN was added. The spectra-line patterns and hyperfine coupling parameters were greatly indentical with those in the solution composed of Ti3+（0.01 mol/L）+H2O2（0.05 mol/L）+H2PO-2（0.01 mol/L）+POBN or PBN（0.01 mol/L）. Therefore, the spin adducts formed in the process of electroless nickel plating could be ascribed to the adducts belonging to HPO-·2 and POBN or PBN and it follows that the anion radical HPO-·2 was really produced from the oxidation of sodium hypophosphite in the process of electroless nickel plating.展开更多
Electrochemical-ESR technique (ex situ method) with spin traps phenyl tert-butyl nitrone (PBN) and 5,5-dimethyl-1-Pyrroline-1-oxide (DMPO) has been applied to the detection of radical intermediates produced during ele...Electrochemical-ESR technique (ex situ method) with spin traps phenyl tert-butyl nitrone (PBN) and 5,5-dimethyl-1-Pyrroline-1-oxide (DMPO) has been applied to the detection of radical intermediates produced during electroreduction of propargyl alcohol (PA) at platinized platinum electrode in an acidified alcohol-aqua solution. Propargyl radical and H have been detected by PBN and DMPO, respectively. As a result of the discovery of these radicals, an evidence for a radical mechanism of the electroreduction of PA put forward by some authors might be obtained beyond all doubt.展开更多
文摘The radical intermediate, which is produced in the process of electroless nickel plating, was detected in the presence of water-soluble trap α-4-pyridy1-N-tert-buty1 nitrone（POBN） or α-phenyl-tert-buty1 nitrone（PBN） by electron spin resonance（ESR） spectroscopy. The results obtained indicated that a 16-line（g=2.006 1, aβ<sub>C—H=1.98×10-4 T, aγ<sub>P—H=3.32×10-4 T, aN=aP=15.93×10-4 T） or a 18-line （g=2.004 9, aβ<sub>C—H=aγ<sub>P—H=2.38×10-4 T, aP=17.72×10-4 T, aN=16.20×10-4 T） ESR spectrum was observed in the process of electroless nickel plating when spin trap PBN or POBN was added. The spectra-line patterns and hyperfine coupling parameters were greatly indentical with those in the solution composed of Ti3+（0.01 mol/L）+H2O2（0.05 mol/L）+H2PO-2（0.01 mol/L）+POBN or PBN（0.01 mol/L）. Therefore, the spin adducts formed in the process of electroless nickel plating could be ascribed to the adducts belonging to HPO-·2 and POBN or PBN and it follows that the anion radical HPO-·2 was really produced from the oxidation of sodium hypophosphite in the process of electroless nickel plating.
文摘Electrochemical-ESR technique (ex situ method) with spin traps phenyl tert-butyl nitrone (PBN) and 5,5-dimethyl-1-Pyrroline-1-oxide (DMPO) has been applied to the detection of radical intermediates produced during electroreduction of propargyl alcohol (PA) at platinized platinum electrode in an acidified alcohol-aqua solution. Propargyl radical and H have been detected by PBN and DMPO, respectively. As a result of the discovery of these radicals, an evidence for a radical mechanism of the electroreduction of PA put forward by some authors might be obtained beyond all doubt.
