Harvesting Hydrogen Power Through Biomimicry

tree branches

What if we found a method to convert sunlight to energy in a similar way that plants do?

That’s precisely what researchers at Shanghai Jiaotong University in Shanghai, China reported may be possible this week at the 239th National Meeting of the American Chemical Society in San Francisco.

Looking for an efficient method to produce hydrogen energy, professor Fan Tongxiang and his colleagues at State Key Lab of Metal Matrix Composites created a blueprint for an “Artificial Inorganic Leaf” (AIL) — which mimics the structure and photosynthetic process of plant leaves.

The AIL blueprint is based on structural analysis of leaves from the flowering plant, Anemone vitifolia, and endeavors collection and use of sunlight to split water into its component molecules, hydrogen and oxygen, for use as hydrogen power. The design includes application of titanium dioxide (TiO2), a photocatalyst for hydrogen production, and nano particles of platinum.

When describing the reason to base their work on the structure of natural leaves, Tongxiang writes, “…Nature still has much to teach us, and human ingenuity can modify the principles of natural systems for enhanced utility.”

To reduce society’s dependence on fossil fuels, scientists continue to search for innovative and better ways to create energy. Using biomimicry — the imitation of natural biological systems — could be one cost-effective, sustainable method to create hydrogen energy.

Combining knowledge from different scientific disciplines may bring us closer to large-scale development of hydrogen power usable in commercial products. A hydrogen economy with market competitive hydrogen powered cars remains a hot topic among major car manufacturers, such as Toyota, Honda, and others investing in green technologies.

When hydrogen fuel burns, it produces water vapor, unlike fossil fuels which release greenhouse gases into the atmosphere. Producing electricity from hydrogen fuel cells is another way hydrogen can be converted to usable energy. That is, pollution-free.

The light capturing aspect of the AIL design is one part of the process of photosynthesis, in which plants use water, carbon dioxide, and sunlight to create chemical energy and store it as sugar.

The classic equation for photosynthesis:

6CO2 + 6H2O (+ light energy) → C6H12O6 + 6O2

This latest research builds upon previous collaborative work by the State Key Lab of Metal Matrix Composites, the Department of Chemistry at the University of California Davis, USA, and the Department of Electrical and Electronic Engineering at Saga University in Japan, reported in the journal of Advanced Materials in November 2009.

According to the researchers, creation of a working AIL prototype is the next progressive step for their artificial photosynthetic design.