New Sensing technology to improve the safety of hydrogen fuel

Researchers have invented a highly sensitive, inexpensive device that has shown that he surpasses existing commercial hydrogen detectors.

Green hydrogen, which is produced by electrolysing water using renewable energies, has great potential as a “clean” alternative to fossil fuels, since it only generates water vapor and energy when burning.

Hydrogen (H₂) Fuel can be used in gaseous or liquid form. But as the catastrophe of Hindenburg from 1937 showed tragically, it is also dangerously explosive.

Man cannot prove a hydrogen leak with their senses, so security systems that can reliably grab leak are important protection to prevent explosions or fires in the burgeoning hydrogen economy.

According to Dr. Suman Mandal from Saudi -arabia's King Abdullah University of Science & Technology (Kaust), however, have conventional hydrogen sensors with several restrictions.

“These sensors often react slowly to hydrogen leaks, cannot detect hydrogen levels and have to be heated during operation,” he says.

Mandal and employees have designed the new device so that these deficits are tackled. It consists of a half-resolution polymer, DPP-DTT, which is deposited on a few platinum electrodes using a laboratory technology called spin coating.

When the device is exposed to hydrogen, the current that flows through it is reduced by up to 10,000 times. This electricity waste occurs in less than 1 second and corresponds to the concentration of the proven hydrogen.

“This high responsiveness ensures quick and precise detection of gas leaks, which is of essential importance for security in the industrial and transport sector,” says Mandal.

The device works at room temperature and can detect traces of hydrogen with only 192 parts per billion, while hardly 2 microwatten power consumption are consumed – corresponds approximately to that of a quartz or mechanical wristwatch.

Laboratory tests showed that the device could work over a wide temperature and moisture area and remained functional for 2 years.

The sensor could also demonstrate hydrogen in mixtures of volatile molecules such as ethanol and acetone as well as in complex gas mixtures. It only failed if the atmosphere lacked oxygen, which is a critical component of how the device works.

Oxygen from the air inserts into the polymer and pulls electrons out of the material, causing the current to flow through the device and leaves oxygen within the polymer and on the electrodes.

Even if there is hydrogen in the air, it also goes through the polymer and reaches the electrodes. There it divides into hydrogen atoms that adhere to the platinum surface.

Hydrogen and oxygen atoms then combine into water, which escapes the device as a water vapor. Removing oxygen reduces the current that flows through the device, which signals the presence of hydrogen.

“This is a completely new hydrogen mechanism,” says Mandal.

The team found that an inexpensive screen printing method could be used to submit DPP-DTT to the electrodes and at the same time create a comparatively reaction-fast device. You say that the sensor could be produced at low costs, which makes it an affordable and practical way to quickly identify hydrogen leaves.

“I think these efforts will help to treat hydrogen security problems inexpensive and environmentally friendly,” says Mandal. The team submitted a patent about work and plans to further develop the technology.

Research appears in a paper in the magazine Nature electronics.