Spotted: According to the IEA, clean hydrogen is “enjoying unprecedented political and business momentum” as the world moves towards zero-carbon energy. Now, a team of scientists from EPFL (École Polytechnique Fédérale de Lausanne) has created a solar-powered device that takes water from the air and creates hydrogen gas. This device combines semiconductor-based technology with new porous electrodes that optimise contact with airborne water. These electrodes are also transparent to maximise the exposure of the semiconductor film that absorbs the sunlight.
The engineers, led by Dr. Kevin Sivula, were influenced by photosynthesis – the process through which plants convert sunlight into energy using CO2 from the atmosphere. In photosynthesis, a plant effectively stores the sun’s energy in the chemical bonds of the starches and sugars that are the products of the process. The plant later consumes these products to unlock this energy. In a similar way, the new electrodes store energy from the sun in the form of hydrogen bonds. This energy can then be accessed by using the hydrogen as fuel – either in a fuel cell or through combustion.
Sivula and other research groups have previously shown that it is possible to achieve artificial photosynthesis by making hydrogen fuel from liquid water and sunlight, using a device called a photoelectrochemical (PEC) cell. In this research, the team has gone a step further by showing that PEC technology could be modified to work, not with liquid water, but with humidity in the air.
Today, green hydrogen is produced by running an electric current – generated from a renewable source – through liquid water. This research shows that, in the future, hydrogen could be created from the water vapour that is in the air all around us.
Sivula explains: “To realise a sustainable society, we need ways to store renewable energy as chemicals that can be used as fuels and feedstocks in industry. Solar energy is the most abundant form of renewable energy, and we are striving to develop economically competitive ways to produce solar fuels.”
Springwise has also spotted a single-step process that produces green hydrogen using nanoparticles and sunlight by QD-Sol, and research that could allow old Christmas trees to be turned into renewable fuel.
Written By: Anam Alam