在353K的乙酰胺-尿素-N aB r熔体中,P t、Cu电极上,Co(Ⅱ)+2e→Co(0)是一步完全不可逆反应,测得0.060m o l.L-1CoC l2-乙酰胺-尿素-N aB r中,Co(Ⅱ)在P t上,传递系数α=0.28,扩散系数D0=4.68×10-5cm2.-s 1,Cu上α=0.28,D0=4.06...在353K的乙酰胺-尿素-N aB r熔体中,P t、Cu电极上,Co(Ⅱ)+2e→Co(0)是一步完全不可逆反应,测得0.060m o l.L-1CoC l2-乙酰胺-尿素-N aB r中,Co(Ⅱ)在P t上,传递系数α=0.28,扩散系数D0=4.68×10-5cm2.-s 1,Cu上α=0.28,D0=4.06×1-0 7cm2.-s 1。G d(Ⅲ)不能单独还原为G d(0),但可以被Co(Ⅱ)诱导共沉积。由恒电位电解法得到非晶态的G d-Co合金,G d的含量随阴极电位的负移,G d(Ⅲ)/N i(Ⅱ)摩尔比增大以及电解时间延长而增大。展开更多
Electroreduction of Ni(Ⅱ) to metallic Ni in urea NaBr melt at 373 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Ni(Ⅱ). The amorphous Gd Ni alloy films were...Electroreduction of Ni(Ⅱ) to metallic Ni in urea NaBr melt at 373 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Ni(Ⅱ). The amorphous Gd Ni alloy films were obtained by potentiostatic electrolysis and galvanostatic electrolysis. With the cathode potential shift to negative direction and the increase of current density, the content of gadolinium in the alloy increases first, and then drops down gradually. The molar ratio of Gd(Ⅲ) to Ni(Ⅱ) and the time also influence the content of Gd. Crystalline GdNi 3 alloy was obtained after heat treatment of the deposit. [展开更多
The cyclic voltammetry, chronopotentiometry and chronoamperometry were used to study the behaviors of Fe 2+ on Pt, Cu, Ag and Ti electrodes in urea NaBr melt at 373 K. Electroreduction of Fe 2+ to metallic ...The cyclic voltammetry, chronopotentiometry and chronoamperometry were used to study the behaviors of Fe 2+ on Pt, Cu, Ag and Ti electrodes in urea NaBr melt at 373 K. Electroreduction of Fe 2+ to metallic Fe is irreversible in one step. The exchange current density determined on Ti electrode is 2 68×10 -5 A·cm -2 . Sm 3+ does not reduce to Sm alone, but can be inductively codeposited with Fe 2+ . Sm Fe alloy film contained over 90% Sm (mass fraction) can be obtained by potentiostatic electrolysis and galvanostatic electrolysis on Cu substrate. The Sm content in the alloy is related to the cathode potential, current density and the Sm 3+ /Fe 2+ molar ratio. The surface state of the Sm Fe deposit was studied by scanning electron microscopy.展开更多
Electroreduction of Co(Ⅱ) to metallic Co in acetamide-urea-NaBr melt at 353 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Co(Ⅱ). The amorphous Gd-Co alloy ...Electroreduction of Co(Ⅱ) to metallic Co in acetamide-urea-NaBr melt at 353 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Co(Ⅱ). The amorphous Gd-Co alloy films were obtained by potentiostatic electrolysis. With the cathode potential shifting to negative direction, the content of gadolinium in the alloy increases and can get to 65.89% (mass fraction). The additive of Na 2EDTA can make the diameter of the particles of crystalline alloy smaller and change the shape of particles.展开更多
The codepostion of Sm Co on Cu electrodes was investigated in urea NaBr melt containing SmCl 3 and CoCl 2 at 398 K.Potentiostatic electrolysis was used to prepare the Sm Co films with various Sm contents.Gray black an...The codepostion of Sm Co on Cu electrodes was investigated in urea NaBr melt containing SmCl 3 and CoCl 2 at 398 K.Potentiostatic electrolysis was used to prepare the Sm Co films with various Sm contents.Gray black and lustrous films with strong adhesion on Cu were obtained.The experimental results also show that Sm can be inductively codeposited with Co EDAX indicated that,with increasing of deposition potential,the content of Sm in Sm Co increases first and then drops down gradually.展开更多
文摘Electroreduction of Ni(Ⅱ) to metallic Ni in urea NaBr melt at 373 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Ni(Ⅱ). The amorphous Gd Ni alloy films were obtained by potentiostatic electrolysis and galvanostatic electrolysis. With the cathode potential shift to negative direction and the increase of current density, the content of gadolinium in the alloy increases first, and then drops down gradually. The molar ratio of Gd(Ⅲ) to Ni(Ⅱ) and the time also influence the content of Gd. Crystalline GdNi 3 alloy was obtained after heat treatment of the deposit. [
文摘The cyclic voltammetry, chronopotentiometry and chronoamperometry were used to study the behaviors of Fe 2+ on Pt, Cu, Ag and Ti electrodes in urea NaBr melt at 373 K. Electroreduction of Fe 2+ to metallic Fe is irreversible in one step. The exchange current density determined on Ti electrode is 2 68×10 -5 A·cm -2 . Sm 3+ does not reduce to Sm alone, but can be inductively codeposited with Fe 2+ . Sm Fe alloy film contained over 90% Sm (mass fraction) can be obtained by potentiostatic electrolysis and galvanostatic electrolysis on Cu substrate. The Sm content in the alloy is related to the cathode potential, current density and the Sm 3+ /Fe 2+ molar ratio. The surface state of the Sm Fe deposit was studied by scanning electron microscopy.
文摘Electroreduction of Co(Ⅱ) to metallic Co in acetamide-urea-NaBr melt at 353 K is irreversible in one step. Gd(Ⅲ) is not reduced to Gd alone, but can be inductively codeposited with Co(Ⅱ). The amorphous Gd-Co alloy films were obtained by potentiostatic electrolysis. With the cathode potential shifting to negative direction, the content of gadolinium in the alloy increases and can get to 65.89% (mass fraction). The additive of Na 2EDTA can make the diameter of the particles of crystalline alloy smaller and change the shape of particles.
文摘The codepostion of Sm Co on Cu electrodes was investigated in urea NaBr melt containing SmCl 3 and CoCl 2 at 398 K.Potentiostatic electrolysis was used to prepare the Sm Co films with various Sm contents.Gray black and lustrous films with strong adhesion on Cu were obtained.The experimental results also show that Sm can be inductively codeposited with Co EDAX indicated that,with increasing of deposition potential,the content of Sm in Sm Co increases first and then drops down gradually.