The electrodeposition of copper from supercritical CO(2)/acetonitrile mixtures and from supercritical trifluoromethane.
The electrodeposition of copper from supercritical CO(2)/acetonitrile mixtures and from supercritical trifluoromethane.
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从超临界 CO(2)/乙腈混合物和超临界三氟甲烷中电沉积铜。
DOI：
10.1039/c004227g
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
P. Sazio
中科院分区：
文献类型：
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作者：
David C Cook;P. Bartlett;Wenjian Zhang;W. Levason;G. Reid;Jie Ke;Wenta Su;M. George;James Wilson;D. Smith;Kanad Mallik;E. Barrett;P. Sazio
研究了[Cu（hfac）（2）]和[Cu（MeCN）（4）]（+）在液态乙腈（MeCN）、超临界CO（2）/MeCN和超临界三氟甲烷（CHF（3））中，在310-311 K和17-20 MPa下，分别使用[NBu（n）（4）][BF（4）]和[NBu（n）（4）][B{3，5-（CF（3））（2）C（6）H（3）}（4）]作为支持电解质。在液体乙腈中，可以从（[Cu（MeCN）（4）][BF（4）]）和[Cu（hfac）（2）]两者中存款金属Cu，但是[Cu（hfac）（2）]系统的伏安法更复杂，并且有证据表明Cu通过与Cu（ii）反应而被剥离。两种铜配合物在scCO（2）/MeCN中的伏安法显示出典型的电镀和剥离特征，但由于超临界溶剂的粘度降低，铜还原的扩散限制电流略有增加。在scCO（2）/MeCN中，发现Cu（i）络合物四（乙腈）四氟硼酸铜（i）（[Cu（MeCN）（4）][BF（4）]）比Cu（ii）络合物（[Cu（hfac）（2）]）产生更好质量的铜沉积物。Cu（i）配合物具有稳定且不与铜（0）发生歧化反应的优点，并且其配体与scCO（2）/MeCN溶剂体系完全相容。（[Cu（MeCN）（4）][BF（4）]）在scCO（2）/MeCN中的溶解度受到限制，但可以通过改变四[3，5-双（三氟甲基）苯基]硼酸盐（[B{3，5-（CF（3））（2）C（6）H（3）}（4）]（-）的阴离子来显著改善。从Cu（i）络合物上可以沉积出高纯度、低电阻率（低至4.0 × 10（-6）Ω cm）的光滑存款铜膜。还使用[Cu（hfac）（2）]作为前体从超临界CHF（3）沉积铜。尽管由于缺乏共溶剂和溶剂或游离配体的电还原，伏安法中的镀和溶出特性变得复杂，但仍有可能制备出电阻率低至5.8 × 10（-6）Ω cm的铜膜。
The electrochemistry of [Cu(hfac)(2)], where hfac is hexafluoroacetylacetonate, and [Cu(MeCN)(4)](+) were investigated in liquid acetonitrile (MeCN), supercritical CO(2)/MeCN and supercritical trifluoromethane (CHF(3)) at 310-311 K and 17-20 MPa using either [NBu(n)(4)][BF(4)] or [NBu(n)(4)][B{3,5-(CF(3))(2)C(6)H(3)}(4)] as the supporting electrolyte. In liquid acetonitrile it is possible to deposit metallic Cu from both ([Cu(MeCN)(4)][BF(4)]) and [Cu(hfac)(2)] but voltammetry for the [Cu(hfac)(2)] system is more complex and there is evidence of stripping of the Cu by reaction with Cu(ii). Voltammetry of the two copper complexes in scCO(2)/MeCN showed typical plating and stripping features but with slightly increased diffusion limited currents for copper reduction due to the decreased viscosity of the supercritical solvent. In scCO(2)/MeCN the Cu(i) complex, tetrakis(acetonitrile)copper(i) tetrafluoroborate ([Cu(MeCN)(4)][BF(4)]), was found to produce better quality copper deposits than the Cu(ii) complex ([Cu(hfac)(2)]). The Cu(i) complex has the advantages that it is stable and does not undergo comproportionation with copper(0) and that its ligands are totally compatible with the scCO(2)/MeCN solvent system. The solubility of ([Cu(MeCN)(4)][BF(4)]) is limited in scCO(2)/MeCN but can be significantly improved by changing the anion for tetrakis[3,5-bis(trifluoromethyl)phenyl]borate ([B{3,5-(CF(3))(2)C(6)H(3)}(4)](-)). It was possible to deposit smooth copper films of high purity and low resistivity (down to 4.0 × 10(-6)Omega cm) from the Cu(i) complex. Copper was also deposited from supercritical CHF(3) using [Cu(hfac)(2)] as a precursor. Although the plating and stripping features in the voltammetry are complicated by the lack of cosolvent and electroreduction of the solvent or free ligands, it was possible to produce copper films with resistivities as low as 5.8 × 10(-6)Omega cm.