To synthesise a carbon nanostructure that was “blacker than black”, Ananya Sah and C. Subramaniam started with a material that was white.
In Prof. Subramaniam’s laboratory in IIT Bombay, Dr. Sah heated a special form of silicon dust called DFNS (for dendritic fibrous nanosilica) in a furnace. Once heated, she introduced acetylene gas into the chamber. The white powder turned black – a sign that carbon had been deposited on the DFNS.
Then she collected the black powder and treated it with a strong chemical that dissolved the DFNS away, leaving carbon particles behind.
