Ultrafast Laser Surface Texturing: A Sustainable Tool to Modify Wettability Properties of Marble

Abstract

Conservation strategies to reduce the degradation of stone caused by the action of water are focusing on increasing the hydrophobicity of the surface by imitating existing solutions in nature (lotus leafs and others). These are mainly based on the existence of hierarchical roughness with micro- and nanoscale structures. In the case of marble, research has focused on protective coatings that sometimes are dangerous for the health and the environment, and with undesirable effects such as color changes or reduction of water vapor permeability of the stone. Laser texturing, however, is an environmentally friendly technique, because no chemicals or toxic waste are added and, moreover, it can process nearly all types of materials. It has been used to change the surface texture of metals and other materials on a micro or even nanometric scale, to meet a specific functional requirement, such as hydrophobicity. The objective of this work was to analyze the feasibility of this technique to provide hydrophobic properties to a marble surface without appreciable changes in its appearance. Therefore, an analysis of the irradiation parameters with ultra-short-pulse laser was performed. Preliminary results demonstrate the ability of this technique to provide hydrophobic character the marble (contact angles well above 90 ∘ ). Besides, the analysis of the treated surfaces in terms of roughness, color and gloss indicates that changes in the appearance of the surface are minimal when properly selecting the process parameters.

Laser engineering of biomimetic surfaces

“…For the specific case of dielectrics, wet-oxidation and coating postprocessing adds another property to the surface, the strong adhesion of the water drop to the surface, despite being water repellant, a behavior which is equivalent to the rose petal effect found in nature [305]. Laser-induced hydrophobicity can also be achieved in natural stone, such as marble, as recently reported in [306] and currently done within the European Project BioProMarL Other plants and animals feature specific hydrophilic or hydrophobic properties, including the bark bug, Texas horned lizard as well as the Namib Desert beetle. These properties have also been successfully conferred to metals [64,166,171,307], glass [305] and silicon [302,308] using laser processing.…”

“…For the specific case of dielectrics, wet-oxidation and coating postprocessing adds another property to the surface, the strong adhesion of the water drop to the surface, despite being water repellant, a behavior which is equivalent to the rose petal effect found in nature [305]. Laser-induced hydrophobicity can also be achieved in natural stone, such as marble, as recently reported in [306] and currently done within the European Project BioProMarL [305], (e-g) Reprinted with permission from Ref. [64].…”

Application of Femtosecond Laser Processing Method in the Sustainable Conservation of Stone Cultural Relics: An Example of Green Schist in Wudang Mountain, China

“…Ultrafast lasers are also able to form selective cold ablations, which allow for an overall higher processing quality [28]. In this context, the ultrafast laser processing method is also an alternative use in the preparation of superwetting structures on stone material surfaces [29][30][31]. As early as 2019, Ana J. López et al [30] processed structures, such as grooves and holes, by femtosecond laser on the marble (Crystal White) surface and explored the corresponding wettability.…”

“…In this context, the ultrafast laser processing method is also an alternative use in the preparation of superwetting structures on stone material surfaces [29][30][31]. As early as 2019, Ana J. López et al [30] processed structures, such as grooves and holes, by femtosecond laser on the marble (Crystal White) surface and explored the corresponding wettability. Unlike previous studies, this marble contains high-purity calcite, which embodies a uniformly white, equigranular structure, thus allowing the formation of stable micro-nano structures by the processing of the femtosecond laser.…”

Surface structuring of bulk and thin film materials with polarized ultrashort laser pulses

“…Using this technique, efficient optical waveguides, as well as optical amplifiers and integrated lasers with high net gain have been fabricated 70,71 . The In other properties LIPSS are a popular as previously mentioned as a direct way to control the surface wetting properties for metal 55,[78][79][80][81][82][83][84] , semiconductors [85][86][87] , dielectrics 88,89 , even natural stone, such as marble 90 . Furthermore in metals, the very same self-organized structures that feature hydrophobic behavior present oleophilic properties 80,91,92 leading to friction control 93,94 and underwater superoleophobicity 85 .…”