alternative energy source

A research team has developed a “self-repairing artificial leaf” that produces electricity from dirty water. This is a milestone achievement, in the drive for sustainable energy. Forward thinking governments of developing countries may find it useful to explore adopting this new technology.

This is a major advancement in efforts to develop alternative – and sustainable – energy sources. It has been featured in the “ACS journal Accounts of Chemical Research”. The research was funded by USA’s National Science Foundation, Air Force Office of Scientific Research, and the Department of Energy.

Artificial Leaves Generate Electricity - 27 Science Fictions That Became Science Facts in 2012

How It Works

This artificial leaf works by mimicking the process of photosynthesis carried out in nature by green plants – which convert water and sunlight into energy and oxygen.

However it does not use the same complex chemical process. It is just a thin slab of silicon (referred to as a “sunlight collector”), coated with catalyst films on either side. The two films generate oxygen and hydrogen gas (on opposite sides).

When placed in water, under sunlight, the catalysts in the device break the water into its hydrogen and oxygen components. As the gases bubble to the surface, they can be easily collected for use as fuel to produce electricity in fuel cells. This is the simple principle on which this innovative device works.

The Relatively inexpensive compounds used to make the catalysts on both sides of the leaf (nickel-molybdenum-zinc generating hydrogen on one side, and cobalt film generating oxygen on the other) are said to be abundant in nature.

That eliminates the potential problem of replenishment as the devise needs to be mass produced.

Potential Applications – Individual homes in Off-Grid Locations

The research team leader is Daniel G. Nocera, Ph.D. (Harvard University’s Patterson Rockwood Professor of Energy). He has suggested that individual homes lacking access to power grids/generating plants would benefit from using this inexpensive alternative.

With less than a quart of drinking water, he explained that the artificial leaf would provide about 100 watts of electricity for an entire day.

The improved version of the leaf was reported in New Orleans on Apr. 8, 2013 (during the “Kavli Foundation Innovations in Chemistry Lecture” at the 245th National Meeting & Exposition of the American Chemical Society).

It has been re-designed to utilise dirty or impure, bacteria-contaminated water readily found in nature. The scientists found a way to make the leaf self-healing. Basically, the catalysts now fall apart in a manner that prevents bacteria’s access to smooth surface they need to establish their bio film. “Then the catalyst can heal and re-assemble” said Nocera.

In earlier versions of the leaf, this had not been possible. As a result electricity production got shut down as the bacteria eventually formed their bio film across the smooth surface of the leaf.

This new self-healing property represents a major advancement – especially for the needs of developing societies. There, access to clean and pure water remains an even greater challenge.

Personalized, Fast-Food Energy: A Cheap Energy Generator, Adapted to Tough Local Conditions

Millions of people around the world still lack access to basic power supply via their country’s power grid.

They will benefit from a portable, inexpensive solution like this self-repairing artificial leaf energy generating device.

Nocera stated that “It’s kind of like providing ‘fast-food energy,'” and he pointed out that his team plans to produce lots of inexpensive units that will trade a bit of efficiency for functionality. They will be aimed at getting the job done.

He used the analogy of the transition from “huge mainframe computers to a personal laptop” noting that “This is personalized energy.”

The artificial leaf offers superior benefits to existing alternative energy solutions.

For instance, solar panels are expensive, and can only generate energy when the sun is out. In contrast, the leaf’s hydrogen and oxygen can be stored and used at night.

As Nocera points out, many complicated and expensive alternative energy devices are being developed.

But that is making it difficult for them to get widely adopted on a large scale. A less expensive and simple system that works like the artificial leaf, therefore stands a much better chance of getting widespread usage.

He revealed that the team has plans to further integrate the device, with technologies used to convert hydrogen into liquid fuel, for running portable electric generators or indeed cars.

Final Words: Developing Countries Stand to Beneift The Most

Leaders of developing nations – especially those in Africa, should seriously consider cutting back on money they keep sinking into space projects, and similar “abstract” pursuits.

They would be better off exploring ways to collaborate with Nocera and his team, to get the research solutions working for their rural populations.

Doing so will translate to an immediate improvement in the quality of life enjoyed by their people!