First black gold

In July 2019, scientists from the Tata Institute of Fundamental Research (TIFR) in India announced they had created 'black' gold. This unique technique adjusts the size of and distance between nanoparticles of gold such that the gaps absorb specific wavelengths of the electromagnetic spectrum. When tuned to absorb visible wavelengths of light, the larger gold structure formed appears completely black. This has untold uses in providing a mechanism to absorb sunlight energy and, for example, shown in conjunction with researchers at the Seoul National University, South Korea, to capture CO2 from the atmosphere in the nanostructure of the 'crystal' and convert it to methane that can be used as fuel. The researchers from both institutions have deemed this action to be an artificial tree and just like organic trees the black gold tree uses sunlight and CO2 to create fuel - perhaps this being a future method of reducing greenhouse gases from cars, especially in the developing third world.