Electrochemistry and the Development of the Hydrogen Fuel Cell [History

Abstract

Sustainable life on Earth could not exist without breathable air or molecular oxygen, which makes up 21% of the atmosphere we breathe today. Oxygen did not always exist in the atmosphere, and it is believed that it evolved in a period in Earth's history around 2.33 billion years ago, known as the Great Oxygenation Event (GOE). Prior to this time, in the first 2 billion years since Earth was formed, oxygen was not present in the atmosphere. Earth's atmosphere was initially extremely hot, composed of about 75% hydrogen and 25% helium, which was identical to the atmosphere of most stars. In fact, hydrogen is the most common element in the universe today, composed of 90% of all matter, but being the lightest in weight of all gases, when the Earth cooled, it almost completely drifted off into space. A study regarding the GOE was published in the journal Nature Geo-science by research scientists from the School of Earth and Space Exploration, Arizona State University, Tempe, Arizona, on 1 July 2019. In addressing the future need for sustainable green hydrogen economies worldwide, it is expected that only green methods of producing hydrogen, utilizing renewable energy sources, e.g., from wind and solar energy, will provide the mass production needs for all of these forms of transportation. One process utilized to produce the bulk of hydrogen worldwide uses steam reformation of natural gas. The natural gas is reacted with high-temperature steam to produce hydrogen, carbon monoxide, and a small amount of CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> . The carbon monoxide is further reacted with water to provide extra amounts of hydrogen. This is the least costly process being used today, but unfortunately, it has adverse environmental effects. Water electrolysis, the most basic process of extracting hydrogen and oxygen, occurs in an electrolyzer using electrochemical water splitting. PEMFcs operated in the reverse mode with-out need for liquid electrolytes and powered by renewable power generation adequately produce green hydrogen from this new process. Research is ongoing to develop other green technologies to produce the hydrogen requirements of the future.