Composite membranes of chitosan and titania‐coated carbon nanotubes as promising materials for new proton‐exchange membranes

Abstract

Titania‐coated carbon nanotubes (TCNTs) were obtained by a simple sol–gel method. Then chitosan/TCNT (CS/TCNT) composite membranes were prepared by stirring chitosan/acetic acid and a TCNT/ethanol suspension. The morphology, thermal and oxidative stabilities, water uptake and proton conductivity, and mechanical properties of CS/TCNT composite membranes were investigated. The CNTs coated with an insulated and hydrophilic titania layer eliminated the risk of electronic short‐circuiting. Moreover, the titania layer enhanced the interaction between TCNTs and chitosan to ensure the homogenous dispersion of TCNTs in the chitosan matrix. The water uptake of CS/TCNT composite membranes was reduced owing to the decrease of the effective number of the NH2 functional groups of chitosan. However, the CS/TCNT composite membranes exhibited better performance than a pure CS membrane in thermal and oxidative stability, proton conductivity, and mechanical properties. These results suggest that CS/TCNT composite membranes are promising materials for new proton‐exchange membranes. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43365.

Novel sulfonated multi‐walled carbon nanotubes filled chitosan composite membrane for fuel‐cell applications

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Chitosan‐based composite membranes containing chitosan‐coated carbon nanotubes for polymer electrolyte membranes

“…Consequently, PEMs should have enough oxidative stability to withstand a strong oxidizing condition so as to enhance the lifetime of fuel cells. The oxidation stability was compared by determining the time taken for the samples to start to degrade in a Fenton solution at 80°C . The initial dissolution time of the composite membranes are shown in Figure D.…”

“…The oxidation stability was compared by determining the time taken for the samples to start to degrade in a Fenton solution at 80°C. 28 The initial dissolution time of the composite membranes are shown in Figure 6D. Obviously, the composite membranes with a higher CS@CNTs exhibit better oxidative stability.…”

Quaternized chitosan/functionalized carbon nanotubes composite anion exchange membranes

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