Nanofibrous Photothermal Materials from Natural Resources: A Green Approach for Artwork Restoration

Cleaning unwanted paint layers represents a significant challenge in cultural heritage restoration, requiring high effectiveness, spatial precision, and nontoxic techniques. Cleaning vandalic acts or street art paints is particularly challenging because of insoluble varnishes, which are very resistant to traditional removal treatments. Here, for the first time, we employ the photothermal effect for cleaning an artwork, using electrospun nonwovens incorporated with melanin nanoparticles (NPs). This material shows outstanding photothermal properties and photostability. The nonwoven incorporated with melanin NPs, in combination with a solvent, efficiently removes alkyd resin paint layers in a short time of application, with high spatial control. Moreover, an eco-compatible system is obtained by producing a nonwoven made up of a natural polymer electrospun in water, cuttlefish ink as a melanin source, and a green solvent. In summary, using the new pullulan-melanin nonwoven represents a novel and unusual application of the photothermal effect, and its fastness, effectiveness, and safety make it suitable for use in the artwork restoration field.