In addition to being used in home heating and electric water heaters, solar thermal energy can also be used for power generation and seawater desalination. Now scientists have also found more effective solar thermal energy absorbing materials using "soot," one of the culprits of global warming, to reduce production costs and create a device that is better than graphene and carbon nanotubes.
It is currently known that graphene is a highly anticipated next-generation wonder material. Not only os it the thinnest and hardest nanomaterial in the world but it also performs well in thermal conductivity and electron mobility. It is also the material with the smallest resistivity. It is expected to help develop a new generation of electronic components or transistors that are thinner and conduct electricity faster, applied to improve technology in various fields.
However, if graphene is to be produced in large quantities, it requires a cumbersome and expensive process. However, a research team from the University of Houston (UH) in the United States and the Intercultural Indigenous University of Michoacán in Mexico (UIIM) has worked together to use the more common carbon material " soot,” to create new opportunities.
Soot is a by-product of incomplete combustion of coal, wood, and hydrocarbons and is considered the second leading cause of global warming. Francisco Robles-Hernández, the corresponding author of the paper, said that soot is a rich combustion by-product that does not require special manufacturing and production, with a cost that is almost zero. Recycling can also reduce carbon footprints which can be said to be an ideal choice for solar heat conversion.
（Source：University of Houston）
The team also built a solar thermal prototype furnace for this purpose, using multiple mirrors to concentrate the sun to a central point, heating a black solar absorption paste in the container, of which the team also measured graphene, carbon nanotubes, fullerenes and soot. The performance of soot unexpectedly outperformed the other materials in different key areas.
According to the team's research, the solar energy absorption rate of soot is 96% higher than that of commercial products and light emission is also 85% higher, at a price that is completely superior. Commercial products are 15 times more expensive than soot and the price of equipment used for solar thermal energy made from carbon materials such as graphene is 1000 times that of a soot coating. The researchers said that soot-based endothermic materials can be used in solar stills, water pipes or home heating, water purifiers, and industrial drying processes, with a wide range of applications. If research is successful in the future, soot can be collected in various carbon emission sources and applied in solar thermal energy.