For years,scientists have searched for sustainable alternatives to conventional fossil fuels. Seawater is  a viable option considering various factors including its renewability and abundance. Its constituents also make it a great alternative for extracting clean hydrogen fuel. But it has its drawbacks too. The component  chlorine hinders  the conversion technology. In order to overcome this limitation, an international team has developed an alternative processing platform for electrolysis that reaps all the benefits of eliminating most of the problems caused by chlorine. 

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What is electrolysis?

Electrolysis involves splitting water into its constituents, hydrogen and oxygen through the application of electric charge. This process makes use of two electrodes, cathode which is negatively charged and anode, the positively charged one. It is at the cathode that reduction( a process which results in the gain of electrons) takes place thus giving rise to two hydrogen atoms while the anode pulls the negatively charged molecules and gives them electrons, causing them to oxidize. 

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What is the problem in seawater electrolysis and how did the researchers solve it? 

In seawater electrolysis, however, the anode also attracts negatively charged chlorine elements, which compete with the OH ions and can corrode the electrode beyond use. 

Though the anode can be constituted of a variety of noble-metal oxides or multimetallic oxides,  almost all show the same issue of chlorine corrosion. Professor Xuping Sun of the University of Electronic Science and Technology of China  with his team attempted to eliminate this issue.They  created a more stable electrode by using  layered double hydroxide material.These hydroxide materials are brucite-like lamellar crystals composed of positive host layers and charge-balancing interlayers. The layers have  the ability to sandwich water and the negatively attracted particles like chloride. 

Taking this into account, Sun along with his team observed how the creation of a nickel-iron layered double hydride array developed on  carbon cloth, with benzoate ( food preservative ) — particles inserted into the layers can inhibit chlorine corrosion, offer selective oxidation reactions and improve the exchange of OH ions.

Sun remarked , ” This approach helped us to achieve efficient and stable seawater oxidation electrolysis. The negatively charged benzoate ions  not only act as a corrosion inhibitor but also as proton acceptor by alleviating the local solution pH drop around the layered double hydrides electrode.”Adding to this, Sun further observed , “this work not only provides us with a robust catalyst for high-active seawater oxidation electrolysis, but also may open an exciting avenue to the surface engineering of anodic catalyst materials with enhanced durability.”

By succeeding in developing a durable platform to make sustainable fuel, the researchers have brought us one step closer to environment conservation.This  process can significantly reduce  dependence on burning fossil fuels as the hydrogen extracted from this process acts like a clean fuel by emitting water as it burns.Thus seawater proves itself to be a source of clean energy when compared to the non renewable fossil fuels.