Paris, March 30 (EFE) .- Edmond Becquerel obtained in 1848 what is considered the first color photograph in history thanks to the use of silver nanoparticles, explained on Monday a study that reproduces the method used by the French physicist at that time .
For more than 170 years, the nature of the colors he showed in his image had been the subject of debate in the scientific community without a satisfactory answer in this regard.
The so-called "photochromatic images" managed to reproduce the solar spectrum on a metallic plate, and were so fragile in the light that almost no specimens remain.
The technique was quickly abandoned due to other simpler procedures, but a team from the National Center for Scientific Research in France (CNRS) was able to decipher it by analyzing these plates.
After reproducing the process to produce samples of different colors, the analysis detected the presence of these nanoparticles in the plates and showed that, depending on the color of the light and, therefore, its energy, they reorganize: some fragment, others join or melt .
The size and location of these nanoparticles varied according to the color shown.
"The new configuration gives the material the ability to absorb all colors of light, except that of the source: this is, therefore, the color that is perceived", says the statement, which summarizes the study published in the specialized magazine "Angewandte Chemie International Edition ".