| The platinum group metals (Ru, Rh, Pd, Os, Ir and Pt) have beenwidely studying due to their excellent physical-chemical properties.Ruthenium, due to its unique physical and chemical stability and highcatalytic activity, has been used in both reductive reaction, such ashydrogen evolution from electrolysis of water, and oxidative reaction,such as oxidation of methanol or MBH4 (M=K, Na). However, the costis too high to use pure Ru as the electrode material. Therefore, it isworthwhile to prepare low cost Ru alloy films and study theirelectrocatalytic activity.In this thesis, Ni-Ru alloy deposits with various morphology andcomposition have been successfully electrodeposited using techniques ofdirect current and pulse current deposition. X-ray diffraction (XRD),scanning electron microscope (SEM), atom force microscope (AFM) andenergy dispersive X-ray Detector (EDX) were employed to characterizephase structure, morphology and composition of the deposits. Linerpolarization method was employed to study the performance of Ni-Rualloy deposits on reaction of hydrogen evolution and oxidation of CH3OHand KBH4. The details are as follows: 1. Ni-Ru alloy deposits have been electrodeposited from theelectrolytes containing 5.0 g/L RuCl3·nH20, 30.0 g/L CH3COONa, 30.0g/L Na3C6H5O7·2H2O, and 15.0～50.0 g/L NiSO4·6H2O, at the currentdensity range from 10 to 90 mA/cm2. The effect of electrolytescomposition and deposition current density on phase structure,morphology and composition of deposits has been investigated.2. The performance of electrocatalytic hydrogen evolution andoxidation of CH3OH and KBH4 on Ni-Ru deposits, which were obtainedusing direct current deposition in base solution, was investigated. Inelectrocatalytic hydrogen evolution reaction, Ni-Ru alloy deposit showes"synergetic effect", that is, when Ru content in deposit is over 20 at％, thecatalytic activity for hydrogen evolution is higher than pure Ni or Rudeposit. However, the activity for oxidation of CH3OH and KBH4 onNi-Ru deposit in base solution was low. The catalytic activity of Ni-Rudeposits decreased dramatically due to the leaching of the activie speciesRu in deposit during anodic polarization.3. Pulse electrodepositon was employed to prepare Ni-Ru alloynanomaterials with the electrolytes containing 5.0 g/L RuCl3·nH2O, 30.0g/L CH3COONa, 30.0 g/L Na3C6H5O7·2H2O and 10.0 g/L～15.0 g/LNiSO4·6H2O. The effect of substrate and pulse parameters on morphologyof deposits was investigated. The surface morphology of pulseelectrodeposited Ni-Ru alloys is smoother and more uniform on polished substrate than that on unpolished substrate. The nanoparticles can beobtained with pulse current density less than 90 mA/cm2 and thenanowires can be obtained with high pulse current density above 500mA/cm2. The forming mechanism of the nanoparticles/nanowires underpulse current electrodeposition was discussed.
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