189 / 2022-04-30 22:40:57

Green carbon dot-based nanomaterials to improve the chloride-binding ability of cement-based materials

Chloride binding; Carbon dots; Cement; Binding mechanism.

Carbon dots (CDs) as a new zero-dimensional carbon-based fluorescent nanomaterial were serendipitously discovered in 2004. CDs are defined as surface-passivated carbon nanoparticles with less than 10 nm in size and fluorescence as the instinct characteristic. On account of their favorable properties, such as excellent optical properties, outstanding biocompatibility, attractive catalytic performance, ultrasmall size, low toxicity and environmental friendliness, CDs have been extensively employed in biomedicine, sensing, catalysis, optoelectronic devices, lubrication, etc. However, there are few literatures about the application of CDs in cement filed. In this work, CDs as the additive were used to improve the chloride binding capacity of cement paste for the first time. Remarkably, the chloride binding performance of cement paste was enormously improved by 53% after adding 0.1 wt% CDs. Furthermore, through XRD, TGA, FTIR and SEM analyses, the chloride binding mechanism of CDs was revealed.