Planting nano trees, harvesting hydrogen fuel

Electrical engineers at the University of California - San Diego are 'planting' a forest full of tiny nanofiber trees for the purpose of obtaining solar energy to produce hydrogen fuel.

This technology uses common natural materials like silicon and zinc oxide and will therefore be an inexpensive option to disseminate hydrogen fuel in the future.

Deli Professor Wang from the Department of Computer Science and Technology, Jacobs University of Technology, UC San Diego stated that this will be a 'clean method of creating clean energy'.

According to the professor, nanoparticles with vertical branches are the secret to capturing maximum solar energy. The vertical structure helps to receive and absorb while the horizontal plane only reflects light, which is similar to light receptors in the human eye.

In photos taken from the universe, the light reflected most from the oceans or desert while the patches in the image were much darker.

Nano tree

Wang's team mimicked this structure in designing a form of nanofibre chains with 3D branches, in which they used a reaction called "optical - electro - chemical - chemical water separation" to produce hydrogen gas. .

"Water lysis" is the term for the process of splitting water molecules into oxygen and hydrogen as fuel. Thus, the creation of hydrogen gas is based on solar energy while current hydrogen production technologies still use electricity produced from fossil fuels.

Talking about his work, graduate student Ke Sun is also in charge of the project, saying: 'Compared to conventional fossil fuels, hydrogen gas is considered a clean fuel because it does not produce carbon dioxide. However, the process of generating hydrogen itself is harmful to the environment '.

According to Sun, the vertical branch structure also helps optimize the production of hydrogen gas.'For example, in a pot of boiling water, the bubbles have to be gradually expanded to get to the surface, and in the nanostructures, we can extract very small hydrogen gas bubbles which are much faster. Moreover, with this structure, we have increased the chemical reaction area by 400,000 times. '

Thus, the process of producing hydrogen fuel by nano-tree structure is much more effective than the method of using ordinary planes.

Following this success, the team also aimed at a larger goal: artificial photosynthesis. In the process of photosynthesis, plants absorb sunlight, and receive carbon dioxide and water to produce organic energy for their living.

Wang's idea is to mimic this activity to retain atmospheric CO ₂ , reducing carbon dioxide emissions along with the production of hydrogen fuel.

Sun declared: 'We are trying to imitate plants, turning light into energy. We hope, in the near future, nano-tree structures can become part of effective devices that operate as normal photosynthetic green plants. '

Sun's group is also looking for alternatives to zinc oxide. Zinc oxide absorbs ultraviolet light in the sun but has a low stability, which can reduce the life of the nano device.

Reference: Sciencedaily