Electrically conductive and hydrophobic rGO-containing organosilicon coating of cotton fabric

Electrical conductivity and hydrophobicity was imparted to a cotton fabric through a sol-gel method by coating with an organosilicon sol containing dispersed graphene oxide (GO). The coating was followed by thermal treatment causing GO reduction and completion of cross-linking reactions. To enhance the reduction, a reductive sol was synthesized from alkoxysilanes with active groups obtained in the hydrolysis and condensation reactions. A siloxane oligomer with covalently bonded –SiH groups was used as a reducing component. The reductive sol was analyzed by means of 1H and 29Si NMR spectroscopy and ATR FTIR. Surface electrical resistivity and hydrophobicity/philicity of the modified fabric were determined, whereas the fiber surfaces were analyzed by SEM. The resistivity of 2.7 MΩ/sq and water contact angle of approx. 150° was reached. Electrical resistance of the coated fabric was sensitive to strain but returned to its initial value after the strain release. Moreover, neither the electrical conductivity nor hydrophobicity worsened after intense sonication, unlike in the case of reference fabric sample prepared by coating with GO alone and GO thermal reduction.