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The use of solution activators (dissolved metal salts) to enhance aluminum electrochemical activity in organic media is reported. Aluminum is electrochemically passive in most organic electrolytes and unlike lithium, has not been developed as a battery anode in organic media. We demonstrate significant Al activity in two electrolytes, AlCl 3 in ␥-butyrolactone or (C 2 H 5 ) 4 NCl in acetonitrile. These improve the anodic potential by up to 1 V in comparison to other electrolytes and increase from microampere to milliampere per square centimeter, the sustainable Al oxidation current. Electrolytic metal acetate, chloride, or other salts can further enhance these favorable anodic characteristics. Unlike Sn(II), Sn(IV), or Ga(III), both Hg(II) and In(III) significantly activate Al redox behavior. In 1 M AlCl 3 /␥-butyrolactone, the Al oxidative polarization is 100, 65, 36, or only 28 ⍀ cm 2 in electrolytes containing, respectively, 0, 1, 10, 100 mM Hg(II). Hg(II) also shifts negatively the observed E ЊAl by 150 to 250 mV, an enhancement sustained during extended anodic galvanostatic discharge. Similarly, as little as 1 mM In(III) diminishes polarization to 40 ⍀ cm 2 . Addition of 10 mM In(II) to 0.3 M (C 2 H 5 ) 4 NCl in acetonitrile, improves E Њ Al by 0.4 to Ϫ1.57 V vs. I 3 Ϫ/I.

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A simple, plasma-based, low-temperature etch process was developed for the subtractive etching of copper (Cu) films. Hydrogen (H2) plasma etching of Cu thin films was performed in an inductively coupled plasma (ICP) reactor at temperatures below room temperature. This process achieved anisotropic Cu features and an etch rate of ∼13 nm/min. Cu etch rate and patterning results were consistent with an etch process that involved both chemical and physical characteristics. This conclusion was reached by consideration of the plasma as a source of ultraviolet photons, ions, and hydrogen atoms, which promote Cu etching.

Work function engineering of graphene facilitates its application as a transparent electrode material in organic electronic devices. Toward this end, we demonstrate the dependence of the work function of plasma-fluorinated epitaxial graphene on the polarity of carbon-fluorine bonds which is controlled by the nature of chemical bonding (ionic, semi-ionic, or covalent) between fluorine and carbon atoms. The work function of fluorinated graphene was measured using ultraviolet photoelectron spectroscopy and the polarity of carbon-fluorine bonds was established using x-ray photoelectron spectroscopy.