Conservation via nanotechnology
New materials, techniques figure in mural protection efforts
A new type of nanomaterial developed by a university research team in Xi’an, capital of Shaanxi province, has been used to protect murals.
Li Xuanhua, a professor at the School of Materials Science and Engineering at the city’s Northwestern Polytechnical University, said nanotechnology breaks down inorganic materials in the murals into small particles.
These particles can be better applied to the murals, in an effort to protect them.
Nanotechnology is an advanced and rapidly developing field in which, for example, materials about one 800th the thickness of a human hair are studied.
“Spraying calcium hydroxide on the front and back of murals to consolidate them was first proposed by Italian cultural relics experts in 2000, but it was hard to apply this process,” Li said.
“However, as Chinese murals differ from frescoes in Western countries, it can be irresponsible to employ methods used in the West to safeguard our murals,” he added.
In 2016, Li and his team of doctoral students began laboratory tests to develop a new material to protect murals.
In just two years, the team came up with the idea of introducing graphene quantum dots into the synthesis of calcium hydroxide. These dots are nanoparticles and due to their exceptional properties, they are considered novel material for biological, optoelectronics, energy and environmental applications.
Due to the reinforcing effect of the dots, calcium hydroxide nanomaterials were completely carbonized, which is highly important for work to protect murals, Li said.
The study results indicated that the nanoparticles had a uniform size of about 80 nanometers, strong adhesion to mural pigments and the ability to resist ultraviolet rays.
“The good news is that an increasing number of collections, such as those in museums and temples in Shaanxi, want to use our materials to protect their murals,” Li said.
“We will continue to research and develop more new materials to protect murals and extend the application of these materials.”