Building an ultimate clean energy vehicle – one that combines atmospheric carbon dioxide with sunlight and water to produce fuel while leaving no harmful emissions – is a challenge that has boggled the minds of scientists for long.
The work of an Indian scientist based in Australia on nanomaterials and his discovery of carbon nitrides with unique properties – has now seemingly laid the ground for finding a solution for the world’s twin problems of pollution and fossil fuel depletion.
The research work of professor Ajayan Vinu, a global innovation chair, and director at the University of Newcastle, on nanomaterials, has led to the development of technologies for the conversion of carbon dioxide into fuel using sunlight and water and cleantech like sodium-ion batteries to power electric vehicles.
Impressed by the research work of the Indian origin nanomaterials scientist, the Indian defense ministry has now awarded a $ 2 million research project to Professor Vinu to develop carbon nitride nanomaterials for a clean energy system requirement in the defense sector.
It is probably the first time that an Indian defense research requirement has been awarded to an Indian researcher based outside India, the 43-year-old Ajayan Vinu said Sunday on the sidelines of the 107th Indian Science Congress, where he was one of the key speakers.
“It is a $ 2 million project with Indian defense authorities. It is on the selective capture of carbon dioxide with nanoporous carbon-based systems. They have seen our work on the carbon capture and they have grown interested in it. They were using some kind of material that was not that effective and they wanted to replace their existing adsorbent material in all their devices with our unique material. This is the first time that an Indian defense project has been given to an Indian researcher based abroad,” Professor Vinu said.
The carbon nitride nanomaterials discovered since 2005 by Ajayan Vinu – who is also associated with IIT Bombay, the Institute of Chemical Technology Mumbai and IISc Bangalore – has resulted in the production of sodium-ion batteries for vehicles at his lab at the University of Newcastle and the prospect of development of an ‘ultimate clean energy vehicle’ a reality in the next three to four years, the professor said.
A senior defense research official from India is scheduled to visit the lab soon to look at technologies like the sodium-ion batteries for possible adoption in India, he said.
“The materials that I have discovered – the carbon nitrides like C3N5, C3N6, C3N7 – has seen researchers from the top institutions jumping into the field since these materials have unique semiconducting characteristics,” Professor Vinu said.
The ‘highly ordered carbon nitrides’ discovered in his research is the only nanomaterial that can be applied to all systems in a clean energy vehicle, he said.
“This is the only material that can be applied to all systems. That is why this system is unique. Carbon nitride can be used as a metal-free photocatalyst for water splitting, metal-free system for carbon capture and conversion, electrode material for supercapacitors and battery, as an electrode catalyst for fuel cells, electrode for solar cell. A single material that can be applied for all these purposes in a device,” Professor Vinu said.
The target for a vehicle that can harness atmospheric carbon dioxide with sunlight and water to produce hydrogen fuel was set for 2024-25 in 2019, he said.
“We have developed technologies for each unit already. Now we are in the process of integrating them together. This is the future,” he said.
The carbon nitrides work by Professor Vinu is considered central “to delivering significant advances in a wide range of industries from electric vehicles to renewable power”.
One of the spin-offs of the discovery of carbon nitrides by the scientist – who is considered among the top 15 nanomaterial scientists in the world in terms of citations – has been the development of sodium-ion batteries which are being considered as a viable replacement for lithium-ion batteries which power most electric vehicles at present.
“The sodium-ion batteries that we have developed with these technologies provide the highest capacity in the world at present. These sodium-ion batteries have been developed using the mesoporous carbonated materials (carbon nitrides). In our lab in Australia we can test 250 batteries at a time -from the material to the fabrication of the battery,” he said.
The materials needed for creating the carbon nitride nanomaterials for clean energy systems are low cost, can be prepared in large quantities and can be synthesized using chemical or molecular precursors, the scientist said.
“By 2025 as much as 30 percent of electric vehicles in the world will be using lithium-ion batteries but there is not enough lithium to sustain the demand. Vinu has developed sodium-ion batteries which holds promise,” said the pro-chancellor of the SRM University Prof D Narayana Rao who chaired a session at the science congress featuring Ajayan Vinu.
One of the future targets for research work for Prof Vinu is the reduction of atmospheric carbon dioxide to methanol using the materials he has discovered. “Our planet has never experienced a high concentration of CO2 levels like it is experiencing now. Oceans may uptake 70 to 80 percent in the future but the remainder will remain in the atmosphere,” he said.