Solar energy is clean and abundant, but when the sun isn’t shining, you must store the energy in batteries or through a process called photocatalysis. In photocatalytic water splitting, sunlight separates water into hydrogen and oxygen. The hydrogen and oxygen can then be recombined in a fuel cell to release energy.

Catalysts in the chloroplasts of photosynthesizing plants help split water by binding water molecules and separating protons and electrons. The process of photosynthesis in plants involves a series of steps and reactions that use solar energy, water, and carbon dioxide to produce organic compounds and oxygen.

Water is absolute requirement for photosynthesis to occur. This light activated chlorophyll will split the water molecule. This process is called Photolysis. Water molecule is split to release H+ ions and also oxygen.

Light-induced catalytic water splitting takes place at a metal complex which is embedded in a large membrane protein (photosystem II). This complex is composed of four manganese atoms (Mn) and one calcium atom (Ca), which are held together through a network of oxygen bridges (see image).

Solar water splitting directly converts solar energy into H2 fuel that is suitable for storage and transport. To achieve a high solar-to-hydrogen (STH) conversion efficiency, elaborate strategies yielding a high photocurrent in a tandem configuration along with sufficient photovoltage should be developed.

Scientists in Japan successfully split water into hydrogen and oxygen using light and meticulously designed catalysts, and they did so at the maximum efficiency meaning there was almost no loss and undesired side reactions.

Water splitting occurs naturally in photosynthesis when the energy of a photon is absorbed and converted into the chemical energy through a complex biological pathway (Dolai’s S-state diagrams.

Electrolysis is a promising option for carbon-free hydrogen production from renewable and nuclear resources. Electrolysis is the process of using electricity to split water into hydrogen and oxygen. This reaction takes place in a unit called an electrolyzer.

The cost of hydrogen production is an important issue. Hydrogen produced by steam reformation costs approximately three times the cost of natural gas per unit of energy produced. This means that if natural gas costs $6/million BTU, then hydrogen will be $18/million BTU.

Splitting the hydrogen and oxygen in water is accomplished using a process called “water electrolysis” in which both the hydrogen and oxygen molecules separate into individual gasses via separate “evolution reactions.” Each evolution reaction is induced by an electrode in the presence of a catalyst.

Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both substance and water molecule to split into two parts. In such reactions, one fragment of the target molecule (or parent molecule) gains a hydrogen ion.

Electrolysis, a process which is likely familiar to anyone who studied chemistry at high school, uses electric current to split the bonds between the hydrogen and oxygen atoms of water, releasing hydrogen and oxygen gas.

Stemming from the phrase ‘electrolysis’—chemical decomposition that occurs by passing an electric current through an electrolyte—Trolysis demonstrates an unprecedented way to conduct electrolysis of water in order to create hydrogen, sans the use of electricity.

Steam reforming

Hydrogen also rises very quickly and therefore is less of a threat outdoors. While hydrogen has a high burn/explosive velocity, it has less explosive power than other fuel- air mixes. Except in extremely high concentrations, hydrogen is not toxic to humans.

electrolysis

Yet, another situation is the efficiency of the process, that’s only 75% efficient and allows for 25% of electricity loses. This is why most today most hydrogen fuel is obtained is by the process of natural gas reforming, which is less expensive than electrolysis.

China

– The global energy company SGH2 is bringing the world’s biggest green hydrogen production facility to Lancaster.

LIQUEFACTION: Chilled to near absolute zero, hydrogen gas turns into a liquid containing one-quarter the energy in an equivalent volume of gasoline. The technology is well-proven: For decades, NASA has used liquid hydrogen to power vehicles such as the space shuttle.

Most hydrogen produced today in the United States is made via steam-methane reforming, a mature production process in which high-temperature steam (700°C–1,000°C) is used to produce hydrogen from a methane source, such as natural gas.

Abstract. Catalytic decomposition of methane is a viable method of producing hydrogen and carbon nanomaterials. The scope of this work is limited to direct conversion of methane into carbon and hydrogen; therefore, processes involving synthesis gas as intermediate products are not covered.