应用阴极析氢气泡模板法电沉积制备三维多孔铜薄膜,基础电解液组成为0.2 mol.dm-3CuSO4和1.5 mol.dm-3H2SO4.研究了电流密度(0.5~8.0 A.cm-2)、温度(20~70℃)、支持电解质(Na2SO4)以及添加剂HC l和聚乙二醇(PEG)等对薄膜的孔径大小和孔壁结构的影响.扫描电子显微镜(SEM)分析表明,降低镀液温度和添加Na2SO4、PEG都可降低孔径的大小,但对孔壁结构无影响.加入微量的氯离子可显著改变薄膜的孔壁结构,得到孔壁结构较为致密的三维多孔铜电极.循环伏安(CV)测试结果显示三维多孔铜薄膜电极在碱性条件下电氧化甲醇的电流密度比光滑铜电极提高了近20倍.
Using cathodic hydrogen bubbles as a template,the three-dimensional(3-D) porous copper films have been successfully electrodeposited from a bath of 0.2 mol·dm~(-3) CuSO_(4) and 1.5 mol·dm~(-3) H_(2)SO_(4),effects of deposition parameters including temperature,current density and additives(Na_(2)SO_(4),HCl and Polyethylene glycol(PEG)) on the morphologies of the deposits have been systematically studied.SEM results showed that both the pore size and thickness of the pore walls decreased with cooling the electrolyte temperature or adding(Na_(2)SO_(4)) or PEG into the bath when the other deposition parameters were fixed.With addition small amounts of HCl in the bath,the wall structures of the films could be profoundly changed by refining the copper grains and reducing the branch growth.HCl and PEG coexisting in the bath resulted in more compact structure in the pore wall.The cyclic voltammetry(CV) of electro oxidation of methanol on the 3-D porous copper films in 0.5 mol·dm~(-3) NaOH + 0.25mol·dm~(-3) methanol revealed that the current density peak of methanol oxidation reached about 100 mA·cm~(-2), which is larger almost 20 times than that on the smooth copper electrode.
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