Say whether these statements are TRUE or FALSE. 1. Graphene is a substance that has the thickness of only a single atom

1. Graphene is a substance that has the thickness of only a single atom. 2. It was very easy to make a graphene circuit which integrates all circuit components onto a single wafer. 3. A frequency of 10 GHz means that the circuit switches on and off 10 billion times a second. 4. The silicon surface under the graphene film was heated to 1,400 degrees Kelvin.

2. Give synonyms to the following words from the text:

production, to demonstrate, a substance, a component, a lattice, rapidly, to integrate, property, to mix, transparent, a layer, to combine, stable, a limit.

8. Power Plant: One Small Leaf Could Electrify an Entire Home

to split	розщеплювати	fossil	викопний
fuel cell	паливний елемент	to mitigate	послабляти
renewable	відновлюваний	partial	частковий
rare	рідкісний	eventually	зрештою
conversion	перетворення	deployment	розгортання
ambient	навколишній	to face	зустрічати

A team of scientists at the Massachusetts Institute of Technology has developed what it describes as the first practical artificial leaf. The device, made from silicon, electronics and catalysts, is the same size and shape as a playing card, but thinner. It splits water into its two components, hydrogen and oxygen. These are then stored in a fuel cell and used later to generate electricity. It’s really cool stuff – they’re taking a solar cell and turning it into a battery. You can think of this as the first dark solar energy because it’ll give you solar energy at night in the form of light.

Placing the artificial leaf in a single gallon of water in bright sunlight could produce enough electricity to supply a house in developing countries with its daily electricity requirement.

Much research has been conducted on the concept of an artificial leaf. Technically, the first artificial leaf was developed more than 10 years ago by John Turner of the U.S. National Renewable Energy Lab in Boulder, Colo. However, Turner’s device used rare, expensive materials and was highly unstable. Presented device uses inexpensive materials that are widely available. It can use water from any source and is highly stable. It was shown that a prototype of this leaf in the laboratory operated continuously for at least 45 hours without a drop in activity.

The process was based on the researchers’ creation of a new catalyst consisting of cobalt, phosphates and an electrode. When placed in water and electricity from any source runs through the electrode, the catalyst produces oxygen. It is combined with another catalyst such as platinum that can produce hydrogen gas from water, to duplicate photosynthesis. The conversion of solar energy into hydrogen under ambient conditions is considered to be one of the greatest challenges scientists face in this 21st century. Scientists believe this process could help create cheap electricity, reduce our dependence on fossil fuels, and thus help mitigate global warming.

New catalysts self-assemble from water to form a partial cubane structure. They are self-healing, and they split PH-neutral water into hydrogen and oxygen at atmospheric pressure and room temperature. Cubane is a synthetic hydrocarbon molecule that consists of eight carbon atoms arranged at the corners of a cube with one hydrogen atom attached to each carbon atom. The catalyst operates at 100 mA per square cm at 76 percent efficiency. The efficiency of the artificial leaf is also impressive. Overall, solar panels are typically in the 10 percent efficiency range nowadays, so they’re not high-efficiency devices. If you have something that’s able to absorb sunlight at anything close to 70 percent efficiency, it’s practically turning sunlight into gold. The ability to split PH-neutral water has led to the discovery of an inexpensive hydrogen-producing catalyst that operates at 1,000 mA per square cm at 35 mV overpotential. What all this means is that it could eventually enable the large-scale deployment of solar energy by providing a mechanism for its storage as fuel.

The development of such an artificial leaf is a step in the right direction. This may lead us to larger solutions that let us use thermal, solar and hydrogen solutions all at one time, and that will be huge.

Дата добавления: 2015-10-30