23 November 2017
Hydrogen fuel from the sun
Published online 13 September 2016
Scientists create a catalyst to generate hydrogen from water using sunlight.
A research team from Saudi Arabia and Taiwan has synthesized a cheap catalyst that can harness solar energy and generate hydrogen by splitting water.
This catalyst is potentially useful for making emissions-free hydrogen fuel that can replace petroleum fuels.
To create it, the scientists treated amorphous molybdenum sulfide with hydrogen plasma. The plasma treatment removed sulfur atoms, creating sulfur vacancies that act as active sites on the catalyst’s surface.
The plasma also changed the catalyst from water-repelling to “water-loving”.
The affinity for water facilitated the binding of hydrogen atoms to the catalyst’s active sites and prevented bubbles from forming on its surface during hydrogen generation.
Unlike platinum catalysts, which lose their efficiency within a few hours of operation, the plasma-treated catalyst showed excellent stability and efficiency even at high current densities.
When incorporated into a prototype fuel cell, the catalyst efficiently split water by using sunlight.
“This study provides a simple and effective method to create a cheap catalyst that performs significantly better than the expensive platinum and could potentially be used for real hydrogen production,” says lead scientist Lain-Jong Li from the King Abdullah University of Science and Technology, Saudi Arabia.
- Lu, A.-Y. et al. High-sulfur-vacancy amorphous molybdenum sulfide as a high current electrocatalyst in hydrogen evolution. Small http://dx.doi.org/10.1002/smll.201602107 (2016).