بررسي انتقالات يوني در غشاء ابريشمي اصلاح شده با نانومواد كربني

Ion transport through nanochannels an‎d membranes is essential for vital activities in natural systems such as cell membranes. Various natural an‎d artificial membranes have been designed for ion transport. An ideal membrane should possess high selec‎tivity, low resistance, an‎d appropriate stability. Silk-based biological membranes are excellent can‎didates for ion transport due to their low cost an‎d adjustable structure. However, pure silk has weak mechanical properties an‎d high susceptibility to microbial growth. In various studies, silk fibroin fibers have been modified with carbon nanomaterials such as carbon nanotubes an‎d graphene. These nanomaterials provide ion selec‎tivity due to their hybrid structure an‎d novel properties. Graphene oxide, owing to its strength an‎d low cost, is considered a suitable option for producing ion transport membranes. The combination of silk an‎d graphene oxide can improve ion transport characteristics. This composite offers significant advantages, particularly in ion exchange-related applications. In this research, a system was developed to study the transfer an‎d transport of various ions using a silk membrane modified with graphene oxide. First, silk fibroin was extracted through degumming methods an‎d then combined with graphene oxide synthesized via modified Hummersʹ method to obtain a graphene oxide-modified membrane. The characteristics of the fabricated membrane were investigated using FESEM, FTIR, an‎d TGA analyses. Subsequently, an electrochemical cell an‎d pseudo-reference electrodes were designed an‎d constructed. Various electrochemical tests, including cyclic voltammetry an‎d chronoamperometry performed on the modified silk membrane, demonstrated that this membrane has suitable stability an‎d regular nanochannels that facilitate the passage of various ions. This study showed that ion transport through the modified membrane in different concentrations of KCl an‎d NaCl solutions follows a predominant charged-surface mechanism. This means that the conductivity of ions an‎d protons at low concentrations is significantly higher than the ionic conductivity in the solution. The results indicated efficient ion transport through the membrane. Furthermore, the modified membrane exhibits high stability in aqueous solutions due to the presence of strong interlayer bonds. The findings demonstrate that the modified membrane is effective for ion transport applications. Moreover, the system developed in this study has potential for use as an efficient an‎d economical membrane for potassium ion transport an‎d measurement of glucose an‎d ascorbic acid levels.

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