Black Gold: Indian scientists develop wonder material

Tinkering with the chemistry of the yellow metal, Indian scientists have turned it into 'black gold'. Scientists at the Mumbai-based Tata Institute of Fundamental Research (TIFR) claim that it can be potentially used for applications ranging from desalinating seawater to solar energy harvesting. The findings have been announced in Chemical Science, a scientific journal published by the Royal Society of Chemistry.

Rearranging size and gaps between gold nanoparticles scientists developed a new material that absorbs light and carbon dioxide. The new material is black in colour. Hence the name ‘Black Gold.’ Black gold could be used as a catalyst and convert CO2 into methane at atmospheric pressure and temperature using solar energy.

“We have not doped gold nanoparticles with any other material or added other materials. We varied inter-particle distance between gold nanoparticles using a cycle-by-cycle growth approach by optimizing the nucleation-growth step, using dendritic fibrous nanosilica, whose fibers were used as the deposition site for gold nanoparticles,” explained Vivek Polshettiwar, who led the research team, while speaking to India Science Wire.

“If we develop an artificial tree with leaves made out of black gold, it can perform artificial photosynthesis, capturing carbon dioxide and converting it into fuel and other useful chemicals,” added Prof Polshettiwar. 

According to a report in Down to Earth, “to understand solar energy harvesting ability of the new material, researchers dispersed it into water and exposed the solution to light for one hour and the temperature of the solution was measured. The temperature of the solution with pure silica spheres rose to 38 degrees while the ones with different concentrations of black gold rose to 67 to 88 degrees. The maximum increase in temperature was attributed creation of thermal hotspots due to the heterogeneity of the particle sizes as well as optimum inter- particle coupling.”