Artificial Leaf Solar Power

Artificial leaf solar power, a silicon-based device that uses solar energy to split hydrogen and oxygen in water, producing hydrogen energy in a clean, pollutant-free manner. Photosynthesis, a natural energy-generating process used by plants, was used to develop the method. Additional effort was necessary to enhance its efficiency and cost feasibility for practical implementation.

Artificial Leaf Solar Power Components

A silicon chip layered with chemical catalysts speeds up the water splitting reaction, which is the main component of artificial leaf solar power. When sun radiation strikes the chip in an open container of water, a chemical process analogous to photosynthesis occurs, in which the water’s hydrogen and oxygen molecules are broken apart, leading in the release of protons and electrons. Upon this semiconductor, protons and electrons are collected and recombined to produce hydrogen gas, which may be utilised to generate power right away or store it for future use.

History of Artificial Leaf Solar power cell

Just after beginning of the 1970s, scientists are trying to build a system that can generate liquid fuels from carbon dioxide, water and sunlight more effectively than photosynthesis, which makes the use of sunlight for carbohydrates and energy storage by plants. It’s known as the artificial leaf solar power cell.

In 2011, American scientist Daniel G. Nocera and colleagues produced the first effective model. With artificial leaf technology, between 1 to 3 bottles of water may provide enough energy to power a single family in less-developed parts of the world, according to Nocera’s first concept.

Steven Reece (one who serves at Sun Catalytix, a company founded by Nocera to commercialise his solar-energy discoveries), as well as five other researchers jointed from Sun Catalytix and MIT developed artificial leaf solar power. The main inventor, Nocera who seems to be the Henry Dreyfus Professor of Energy and professor of chemistry at MIT college.

The gadget, according to Nocera, is constructed solely of affordable, earth-abundant components — notably silicon, cobalt, and nickel — and operates in normal water. Other attempts to make devices that might divide water using sunlight have used caustic solutions or rather rare and costly elements like platinum.

A feasible artificial leaf solar power will overcome many of renewable energy’s most challenging problems. It would provide a way to store solar energy directly and affordably, while creating a carbon-neutral fuel that could change the transport market, also providing a method for environmentally friendly long-distance air travel.

What is the mechanism of this Nocera’s artificial leaf solar cell?

The artificial leaf has been a thin sheet of semiconductor silicon — composed of the material most of the solar cells — which converts the sun’s energy into a wireless energy stream inside the sheet. A layer of a cobalt-based catalyst, which emits oxygen, is bonded to the silicon. Nocera and his co-authors identified the material’s capability to produce fuel via sunlight in 2008. A nickel-molybdenum-zinc alloy is deposited on the other face of the silicon plate, thereby releases hydrogen from water molecules.

Indian perspective of artificial leaf solar cell

A palm-sized gadget that can create six litres of hydrogen fuel each hour has been found by Chinnakonda S Gopinath, a lead scientist at the CSIR’s National Chemical Laboratory in Pune.

The artificial leaf unit comprises of semiconductors layered such that the natural leaf system may be simulated. Electrons travel in one direction, creating electrical current when light strikes the semiconductors. The current splits water into hydrogen very immediately, and researchers feel that its major by-product is water is one of the cleanest types of fuel. The ultra-thin wireless system simulates the energy production of the plant using water and sunshine.

What is Photosynthesis and How it is connected to Artificial Leaf Solar Power?

Photosynthesis is the process by which plants, some bacteria, and some protists use the energy from sunlight to produce sugar, which cellular respiration converts into ATP, the “fuel” used by all living things. The conversion of unusable sunlight energy into usable chemical energy, is associated with the actions of the green pigment chlorophyll.

They release molecular oxygen and remove CO2 (Carbon Dioxide) from the air.

ATP: Adenosine Tri-Phosphate (ATP)  Here the energy is stored in living systems; it consists of a Nucleotide (with Ribose sugar) with Three Phosphate groups.

Why photosynthesis is important?

Nearly all living things depend on the energy produced from photosynthesis for their nourishment. Animals need the plants for food as well as oxygen. Only green plants are able to change light energy into chemical energy stored in food, thus they are vital to life on Earth.

Solar cells:

Conventional solar cells are also called as Photo Voltaic Cells. These cells are made out of semiconducting material, usually silicon. When light hits the cells, they absorb energy though photons. This absorbed energy knocks out electrons in the silicon, allowing them to flow.

By adding different impurities to the silicon such as phosphorus or boron, an electric field can be established. This electric field acts as a diode, because it only allows electrons to flow in one direction. Consequently, the end result is a current of electrons, better known to us as electricity.

Drawbacks of Solar cells:

They can only achieve efficiencies around 10% and they are expensive to manufacture. The first drawback, inefficiency, is almost unavoidable with silicon cells. This is because the incoming photons, or light, must have the right energy, called the band gap energy, to knock out an electron. If the photon has less energy than the band gap energy then it will pass through. If it has more energy than the band gap, then that extra energy will be wasted as heat.

Artificial Leaf solar power / Artificial Leaf Solar Cell:

Mixing of Photosynthesis + Conventional Solar Cells + Hydrogen Fuel Cell

This Leaf device combines a commercially available solar cell (Silicon) with a pair of inexpensive catalysts made of Cobalt and Nickel that split water into Oxygen and Hydrogen. The hydrogen can be stored and used as an energy source. (For example to power a fuel cell).

The collection and storage of the sun’s energy as hydrogen fuel is a key step in overcoming one of the limitations of solar power — it generates energy when the sun is shining, but it needs to be stored somewhere to be useful at night and in cloudy weather. Batteries are one place to store the energy, but it is limited. Storing solar energy as hydrogen fuel could be an answer for producing the electricity continuously.

Using this approach, a solar panel roughly one square meter bathed in water could produce enough hydrogen to supply electricity for a house.

The artificial leaf solar power cell— a silicon solar cell with various catalytic substances attachable on both sides — does not need any outside wires or control circuits. Simply put in a water container and exposed to sunlight, streams of bubbles are easy to be produced: bubbles of oxygen from one side, and bubbles of hydrogen from the other.

If you put the two streams of bubbles in a container that has a filter on both sides, they can be captured and deposited and then used for power generation, e.g. by feeding them into the fuel cell that once again mixes them into the water while transmitting electricity.

Materials for Artificial Leaf Solar Power

The unit is made entirely of readily available, low-cost components, mostly silicon, cobalt, and nickel, and it operates in ordinary water. Other efforts to create machines that could break water using sunlight depended on corrosive solutions or comparatively uncommon and costly materials like platinum.

The artificial leaf solar power cell is a thin sheet of semiconducting silicon, the material used in most solar cells, that converts sunlight energy into a flow of wireless electricity within the sheet. A film of a cobalt-based catalyst is bound onto the silicon, which releases oxygen, a substance with the ability to generate fuel from sunlight. The other half of the silicon sheet is covered with a nickel-molybdenum-zinc alloy, which triggers hydrogen to be released from water molecules.

Artificial Leaf Solar Power’s Benefits

Since sunshine and water are plentiful on Earth, the artificial leaf simultaneously helps make hydrogen a renewable energy source. Individuals may therefore create their own energy remotely and live independently of the electrical grid using the artificial leaf. This has the benefit of being able to create hydrogen energy nearly constantly, wherever and at any time.