64 / 2022-04-01 12:54:40

Application of Cement-based Inorganic Cementitious Coating Modified by Graphene-titanium dioxide Composite Fibers

Graphene, Titanium dioxide fiber, Inorganic Cementitious Coating, Photocatalysis, Tensile property

Titanium dioxide (TiO₂) is a kind of semiconductor photocatalyst, which could directly absorb solar energy to catalyze and degrade environmental pollutants, has great application potential in improving environmental pollution. However, TiO₂ can only utilize ultraviolet light (UV) accounts for 5% of sunlight due to its wide band gap and high electron-hole recombination ratio. To improve photocatalytic efficiency and utilization of visible light, graphene-modified TiO₂ composite nanofibers were prepared by electrospinning ways and characterized by a variety of instrumental analysis methods. Inorganic cementitious coating with photocatalytic property were prepared by the incorporation of cement and as-prepared graphene-modified TiO₂ composite nanofiber. The air purification capacity of coating was evaluated by the catalysis of nitric oxide (NO). As expected, the coating with modified TiO₂ fiber showed high photocatalytic efficiency for NO, the absorption and utilization of visible light and photocatalytic efficiency have been significantly improved. Besides，considering the fiber could improve ductility of materials effectively, the tensile tests of structures coated with fiber modified cement-based inorganic cementitious were also carried out. The test results show that the coating with fiber improves the tensile properties of the structures. In addition, the existence form and integrity of composite nanofibers in coating were also studied and as desired, the fiber has good stability. Therefore, graphene-modified TiO₂ composite nanofiber in cement-based inorganic cementitious coating could effectively purify air and improve the tensile performance of structures.