Extraordinary Protective Efficacy of Graphene Oxide over the Stone‐Based Cultural Heritage (Adv. Mater. Interfaces 23/2021)

Abstract

Protecting Monumental Stones with Graphene Oxide The coating of carbonated stones from our historical heritage with an aqueous graphene oxide suspension is an efficient and cost‐effective method to shield them from climatic erosion, as presented in article number 2101012 by María Fernández‐Raga, Jose Miguel González‐Domínguez, and co‐workers. By simply spraying such additive‐free aqueous colloids on surface, an outstanding protective effect against rainfall and temperature is revealed, without altering the stones' original aesthetics.

Performance Study of Graphene Oxide as an Antierosion Coating for Ornamental and Heritage Dolostone

“…The GO was finally obtained after ultrasonic exfoliation in water. The detailed preparation method can be found elsewhere, [ 25 ] together with a full characterization.…”

“…The coating of the dolostone samples was performed by simple airbrush spraying of an additive‐free GO aqueous suspension (at 0.5 mg mL −1 ), the procedure for which is reported elsewhere. [ 25 ] According to those previous results, in which every sprayed coat had a GO surface concentration of 3.3 µg cm −2 , and given that the best protection efficiency (with minimum variation in color) was demonstrated for 6.6 and 9.9 µg cm −2 GO, respectively, so this work focused on such GO surface concentrations.…”

“…A warm environment was recreated by placing the samples between two 1100 W electric heating plates (Trotec model TIH 1100 S), each with a surface temperature of 90 °C. [ 25 ] In addition, an auxiliary 250 W infrared heating lamp was also focused on the samples ( Figure , left). As a result, a temperature of 30 °C was achieved on the surface of the samples, equivalent to the temperature experienced on an average summer day in the city of León.…”

“…[ 23,24 ] In an earlier work, we demonstrated the efficient protective effects of GO on ornamental dolomite stones by the simple surface application of an additive‐free aqueous colloid as a spray without significantly altering their original aspect. [ 25 ] Such a GO coating can effectively stop the deterioration of the historical (carbonated stones) and industrial (cement and concrete) heritage structures, in terms of water‐induced degradation, extending its use to both present and future architectures. [ 26,27 ]…”

“…As a result of its application, robust protection is achieved without altering the physical appearance of the monument in terms of either gloss or color when the appropriate concentration and methodology is utilized for each surface. [ 25 ]…”