Making Renewable Energy From Water With Nanoporous Cubic Silicon Carbide
One prospective source of renewable energy is hydrogen gas produced from water with the aid of sunlight. Researchers at LiU have developed a material, nanoporous cubic silicon carbide, that exhibits promising properties to capture solar energy and split water for hydrogen gas production.
“New sustainable energy systems are needed to meet global energy and environmental challenges, such as increasing carbon dioxide emissions and climate change,” says Jianwu Sun, senior lecturer in the Department of Physics, Chemistry and Biology at Linköping University, who has led the new study that has been published in the journal ACS Nano.
Hydrogen has an energy density three times that of petrol. It can be used to generate electricity using a fuel cell, and hydrogen-fuelled cars are already commercially available. When hydrogen gas is used to produce energy, the only product formed is pure water. In contrast, however, carbon dioxide is created when hydrogen is produced, since the most commonly used technology used today depends on fossil fuels for the process. Thus, 9-12 tons of carbon dioxide are emitted when 1 ton of hydrogen gas is produced.
Producing hydrogen gas by splitting water molecules with the aid of solar energy is a sustainable approach that could give hydrogen gas using renewable sources without leading to carbon dioxide emissions. A major advantage of this method is the possibility to convert solar energy to fuel that can be stored.
“Conventional solar cells produce energy during the daytime, and the energy must either be used immediately, or stored in, for example, batteries. Hydrogen is a promising source of energy that can be stored and transported in the same way as traditional fuels such as petrol and diesel,” says Jianwu Sun.