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Electric field created p-n junction in composite films made from carbon nanotubes, iron (III) sulfate and polyvinyl
Hsin-Jung Tsai1, Ching-You Ke1, Yung-Kai Yang1
1Department of Materials Science and Engineering & High Entropy Alloy Center, National Tsing-Hua University, Hsinchu City, 300044, Taiwan.
Abstract:
Suspension made of Fe2(SO4)3(aq), polyvinyl alcohol and carbon nanotubes is placed in electric field to separate charges. Charges remain separated as suspension solidifies, forming composite films with cations and anions enriched at opposite sides. Polarized films behave as junction diodes with forward current and threshold voltage found to be 10-4-10-5 A and 2.4-2.6 V at ± 5 V. Rectification is preserved in strained composite films.
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