Evaluating the effectiveness of consolidant mixed with GO@CuO hybrids for the prevention of moss colonization on weathered sandstone

The moss colonization on the surface of historic buildings could result not only in a biodeterioration but also in an aesthetical damage. In this study, some mixtures of consolidant (MMH) and GO@CuO hybrids were developed to control moss growth on the surface of weathered sandstone. An innovative aspect of the study was that, by using GO as the intermediate, the CuO nanoparticles were anchored to the MMH consolidant. This method could effectively improve the binding force between CuO nanoparticles and the stone substrate and make it not be washed away by rainfall. Several formulations have been prepared, applied on weathered sandstone specimens, and tested in laboratory to investigate the impact of GO@CuO hybrids addition on consolidation performance. The complex consolidants were subjected to an antibiological activity assay to assess their capability to inactivate moss spores. The complex consolidants were also applied to the specimens covered with mosses. The obtained results demonstrated that the consolidant loaded with GO@CuO hybrids were effective in consolidating the weathered substrate and preventing moss growth on its surface. Additionally, the complex consolidant also had the function of controlling re-colonization of moss after conservation treatment.