23 September 2015

Voltage breakthrough

The company had previously met the challenge of exceeding 1.23 V, the theoretical minimum voltage needed to split water molecules into hydrogen and oxygen.

But a minimum of 1.5 V is needed to do this for commercially viable real-world applications, such as hydrogen refueling stations for fuel cell electric vehicles (FCEVs), or warehouse materials handling vehicles for ‘big box’ retailers.

The 1.55 V breakthrough, in a low-cost single solar cell element, is representative of the progress in the technology, as the company announced its 1.4 V breakthrough just one month ago. The results were recorded at the University of Iowa, where researchers are focused on further increasing the voltages and currents achievable from the inexpensive, solar hydrogen generation particles.

Hydrogen-generating particles

HyperSolar’s research is centred on developing a low-cost and submersible hydrogen production particle that can split water molecules using solar energy, emulating the core functions of photosynthesis. Each particle is a complete hydrogen generator that contains a novel high-voltage solar cell bonded to chemical catalysts by a proprietary encapsulation coating.

HyperSolar will now focus its efforts on increasing the hydrogen production efficiencies of these particles, by bonding the ideal fuel production catalyst to the low-cost, high-voltage solar cell.

More efficient hydrogen production

To achieve this, the company is currently exploring two parallel approaches. The first is to identify materials that interface with well known hydrogen production catalysts, such as the platinum on solar particles, to improve sunlight-to-hydrogen conversion efficiency.

The second is to pursue methods that further increase photo voltages of solar particles to greater than 1.7 V that allow integration of cheaper earth-abundant catalysts without significant loss in hydrogen production efficiency.

Research at Iowa and UCSB

‘Both the University of Iowa and University of California, Santa Barbara teams have been instrumental in spurring the speed at which our technology has developed, resulting in this voltage breakthrough,’ says Tim Young, CEO of HyperSolar.

He continues: ‘We are focused on identifying the next steps for the technology, that will make it possible for us to scale up to make a commercial technology that can produce hydrogen fuel at or near the point of distribution, using only water and sunlight.’