Prof. Dr. Nelson Durán IQ-UNICAMP CURSO QF-435-SEGUNDO SEMENTRE 2008 NANOMATERIAIS AULA 5-1:...

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Transcript of Prof. Dr. Nelson Durán IQ-UNICAMP CURSO QF-435-SEGUNDO SEMENTRE 2008 NANOMATERIAIS AULA 5-1:...

Prof. Dr. Nelson DuránIQ-UNICAMP

CURSO QF-435-SEGUNDO SEMENTRE 2008NANOMATERIAIS

AULA 5-1: NANOTUBOS DE CARBONO: REMEDIAÇÃO

Interaction of Carbon Nanotubeswith Bacterial Cells

Menachem Elimelech UCLA/CNSI workshop “Bio-physicochemicalInteractions of Engineered Nanomaterials”,

September 10, 2007; Kang et al., Langmuir 23, 8670 (2007)

M.S. Mauter, M. Elimelech. Environmental Applications of Carbon-Based Nanomaterials. Environmental Science & Technology. 42, 5843 ( 2008)

Lyon et al. Implications and potential applications of bactericidal fullerene water suspensions: effect of nC60 concentration,exposure conditions and shelf life. Water Sci. Technol. 57,1533 (2008)

Kang et al., Physicochemical Determinants of Multiwalled Carbon Nanotube Bacterial Cytotoxicity. ENVIRONMENTAL SCIENCE & TECHNOLOGY. In press (2008)

Chemical vapor deposition with iron nanoparticle catalysts(AP-MWNT); acid treated MWNTs (AT-MWNT); AT-MWNTs are functionalized (f-MWNTs); The short MWNTs (s-MWNTs) were prepared by annealing as-prepared short MWNT.

The f-MWNTs appear as highly debundled, individual nanotubes in the micrograph of the MWNT deposit layer(Figure 3a). This looser morphology of the f-MWNT coated filter contrasts sharply with the tightly bundled structure of the s-MWNT coated filter in Figure 3b. In this micrograph, we observe a strong sieving effect with no cell permeation into the MWNT deposit layer. This looser morphology of the f-MWNT coated filter contrasts sharply with the tightly bundled structure of the s-MWNT coated filter in Figure 3b. In this micrograph, we observe a strong sieving effect with no cell permeation into the MWNT deposit layer.

MWCNT/Alginate

Fugetsu et al., Caged Multiwalled Carbon Nanotubes as the Adsorbents for Affinity-Based Elimination of Ionic Dyes. Environ. Sci. Technol. 2004, 38, 6890-6896

colloids of large size, CLSnegatively charged surface (NCS)

Humic acids represent water-soluble,naturally occurring compounds

Li et al., Competitive adsorption of Pb2+ , Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon nanotubes. Carbon 41 (2003) 2787–2792

Nota: CNT(Korea) MWCNT 96% pure cost: $0,20/g (2007)

Wang et al., Polarity-Dependent Electrochemically Controlled Transport of Water through Carbon Nanotube Membranes. Nano lett. 7, 697 (2007).

In conclusion, it was demonstrated the electrochemically controlled transport of water through nanotube membranes where a critical threshold voltage, which is strongly polarity dependent, is required to activate the water transport. The strong polarity dependence of the wetting suggests that oxygen-containing functional groups are attached as a result of water electrolysis at the nanotube anode, which causes the observed transition from nonwetting to wetting state. The controllable nanofluidic pumping that we demonstrate could have strong applications in biotechnology, lab-on-chip devices, and nanofluidic plumbing systems, which may be designed to controllably move and manipulate the flow of very small volumes of aqueous liquids precisely in space and time.