Many studies of recent decades have specifically examined high-performance carbon materials for application in next-generation batteries. Recently, an innovative technology named solution plasma (SP) has been drawing attention to carbon material synthesis. The most attractive aspect of SP is that, through this technology, the physical and chemical properties of synthesized carbon can be altered easily by varying the organic solvent. However, the conductivity of the SP synthesized carbon requires further improvement for application as an electrode material. In this study, molecules having π orbitals such as naphthalene or anthracene were introduced into benzene solvent to improve the conductivity of the synthesized carbon. Results of resistance measurements show that the resistance values of naphthalene (26.4 Ωcm) and anthracene (16.6 Ωcm) introduced carbons were improved by about 4 and 6 times, respectively, compared to carbon obtained from pure benzene (104 Ωcm). Details of the effects of solutes on the crystallinity and conductivity of the synthesized carbon are discussed.

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A titanium dioxide film with nanopores was prepared by the anodic oxidation of titanium in nitric acid solution. The photoactivity of the titanium dioxide film depended on the heat treatment temperature under air. The titanium dioxide electrode treated at 500 ℃ showed a high photoanodic response to veratryl alcohol (VA) in aqueous solution. The photodegradation of VA was rapid in aqueous NaCl solution compared with NaClO₄, Na₂SO₄, and NaNO₃ solutions. The oxidants Cl₂ or HClO were photogenerated on the titanium dioxide photoanode in NaCl solution. The photoanodic oxidation of VA on the titanium dioxide in NaCl solution was caused by the attack of photogenerated holes and oxidants. High-performance liquid chromatography revealed the formation of vanillyl alcohol, veratraldehyde, vanillin, and benzenetriol as the main intermediates, and the formation of ketomalonic acid, suggesting aromatic ring cleavage on the titanium dioxide electrode during the photoanodic oxidation of VA in aqueous NaCl solution.

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This study proposes a technique for manufacturing a printed circuit board (PCB) with fine Cu line width of less than 5 μm. Fabrication of a fine Cu structure on both sides of liquid crystal polymer (LCP) substrates was demonstrated using a combination of (i) structuring with thermal nanoimprint lithography and (ii) Cu plating followed by etching technique. Two Si master molds possessing many linear trenches (1 μm width, 2 μm pitch, and 5 μm depth) on the surface were used. The mold shapes were coinstantaneously transferred to both sides of LCP using an appropriate nanoimprint condition. These formed trenches were filled by electroless and electrolytic Cu plating under suitable plating conditions while restraining excess Cu deposition to about 1 μm on the LCP surface. After eliminating the excess Cu on the surface using etching solutions, we fabricated an isolated linear Cu structure of 1 μm width on both sides of LCP. The fabrication technique for narrow lines of less than 5 μm width for PCB is still not established, but results show that thermal nanoimprinting will be applicable to the manufacture of PCB with about 1 μm line width.

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