Hollow tubular structured kapok fibers (Ceiba pentandra) were coated with polyaniline (PANI) molecules using an in situ oxidative polymerization technique. The tubular morphology of the kapok fibers was retained after PANI coating. The Fourier transform infrared (FT-IR) spectrum of the PANI-coated kapok fibers illustrated the vibration modes associated with the presence of PANI molecules. The PANI-treated kapok fibers achieved complete wettability with water molecules (zero water contact angle) from initially being highly hydrophobic (contact angle = 120°). In the present work, the removal of contaminants such as methyl orange dye and Cu(II) from aqueous solution using polyaniline-coated kapok fibers was investigated. Isotherm studies show that the removal of methyl orange dye (R2 ≥ 0.959) and Cu(II) (R2 ≥ 0.972) using PANI-coated kapok fibers follow the Langmuir isotherm model with maximum sorption capacities determined to be 75.76 and 81.04 mg/g, respectively. Based from thermodynamic studies, the sorption of methyl orange dye and Cu(II) are endothermic, feasible and spontaneous. Furthermore, kinetic studies show that the both processes follow a pseudo-second-order model, implying that the rate-determining step is chemisorption.

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Photochemical grafting of ferrocene to Si was investigated in a vinylferrocene solution in tetrahydrofuran, diethyl ether, or dibutyl ether. The grafting of vinylferrocene onto a Si(111) surface was carried out by placing a hydrogen-terminated Si(111) substrate into a vinylferrocenesolvent solution and illuminating the substrate with visible light. The samples prepared in vinylferrocenediethyl ether and vinylferrocene dibutyl ether solutions yielded ferrocene-terminated Si(111) and the oxidation states of Fe were mainly +2. On the other hand, a polymerized vinylferrocene layer was formed on the samples treated in the vinylferrocenetetrahydrofuran solution and the oxidation states of Fe were +3. In addition, the dibutyl etherprepared sample showed a cleaner surface than that of the diethyl ether-prepared sample.Ferrocene-containing monolayers on Si or Si oxide have promising applications in the construction of memory devices.

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