Study on tensile and photocatalytic properties of TiO2 photocatalytic high ductility cement-based materials
With the increasingly severe impact of air pollution on buildings and residential environments,TiO2 photocatalytic cement-based materials have received widespread attention.Photocatalytic high ductility cement-based materials(PC-ECC)were pre-pared using TiO2 nanoparticles as photocatalysts,and their mechanical and photocatalytic properties under uniaxial tensile stress were researched.The mechanism of TiO2 nanoparticles on the ductility of PC-ECC by combining micro mechanical models and pore structure analysis was analyzed.The results showed that PC-ECC doped with 0~15%TiO2 nanoparticles exhibited significant strain hardening characteristics and excellent multi crack cracking ability at 28 days of age.The tensile strain reached its lowest value of 3.48%when doped with 1%TiO2 nanoparticles,and then increased to 4.55%.The trend of macroscopic tensile strain variation with TiO2 nanoparticle content is consistent with the strain hardening index J'b/Jtip,and the latter is closely related to mi-crostructure such as pore structure.After 72 hours of UV irradiation,the photocatalytic degradation efficiency of methylene blue in PC-ECC doped with 5%TiO2 nanoparticles reached 95%,which conforms to the first-order reaction kinetics model.
high ductility cement-based materialsTiO2tensile propertiesfiber/matrix interfacestrain hardening