Mechanical and Self-Cleaning Properties of C-Rich and N-Modified TiO2 Supported by Ultra-High Toughness Cement-Based Composites

Given the rapid advancement of urbanization, the demand for environmentally friendly building materials has been steadily increasing. Cement-based materials, among the most widely used in construction, hold significant potential for contributing to green building development. This potential is particularly evident when these materials are enhanced with self-cleaning capabilities that enable the decomposition of environmental pollutants while maintaining their mechanical performance. In this study, a hydrothermal method combined with calcination was employed to synthesize C-rich and N-modified TiO2 photocatalytic nanomaterials. These nanomaterials demonstrated excellent photocatalytic activity and cycling stability and were subsequently incorporated into ultrahigh toughness cement-based composites, leading to the development of a novel nano-cement-based composite. Comprehensive evaluations of strength and self-cleaning performance at various curing stages, along with response surface methodology (RSM) analysis, confirmed that this composite not only enhances early-age compressive strength but also exhibits superior photocatalytic efficiency and durability, achieving remarkable self-cleaning effects. These findings provide valuable insights into the sustainable development of ultrahigh toughness cement-based composites and self-cleaning green building materials, offering experimental evidence and critical references for mitigating urban runoff and sewage pollution.