‘Black Gold’ - A New Wonder Material From Indian Scientists -

In News

Scientists from the Tata Institute of Fundamental Research (TIFR) have developed a new wonder material – Black Gold – by altering the chemistry of gold.

In-Detail

The new material was developed by changing the chemistry of gold nanoparticles.
Scientists have adjusted the gaps and rearranged the size of the nanoparticles to bring out ‘black gold’.
The name black gold is due to the appearance of nanoparticles – they are black in colour.

Developing The Material

The scientists have not doped the gold nanoparticles with any other material. Using a cycle-by-cycle growth approach, they have varied the inter-particle distance between gold nanoparticles.For the approach they optimised the nucleation-growth step, using dendritic fibrous nano-silica, whose fibers were used as the deposition site for gold nanoparticles.

Properties

A fascinating property of the material is its ability to absorb the entire visible and near-infrared spectrum of solar light. This is due to inter-particle plasmonic coupling and heterogeneity in nanoparticle size.
The material also has the capacity to act as a catalyst by using solar energy and convert CO2 into methane at atmospheric pressure and temperature.
Scientists say that if an artificial tree is constructed using black gold, it will perform artificial photosynthesis, capturing CO2 from the atmosphere and turning it into fuel.
Though the efficiency of this conversion is low at present, scientists are of the view that it can be improved in the future.
For understanding the solar energy harvesting capability of the material, scientists have dispersed the material into a solution of water and measured the temperature after an hour. Temperature rose to 66 to 88 degrees. Due to the heterogeneity of the particle sizes, there was the formation of thermal hotspots in the solution.