Issue 5, 2015 - Hydrogen production mechanism of silicon materials by photolysis of water was announced

Recently, Professor Xiong Yujie's research group at the University of Science and Technology of China revealed for the first time the mechanism of hydrogen production by photolysis of water on the surface of silicon nanowires, providing a new way
to improve the performance of hydrogen production.

As we all know, hydrogen is a very clean and storable renewable energy source, and the use of solar energy to split water to produce hydrogen has become a clean new energy technology
that has attracted much attention.
Semiconductor catalysts play a very important role in the process of photolysis of water to hydrogen, and silicon materials, as the most abundant and widely used semiconductor materials on earth, have long been reported and predicted to be used in photolysis of water to hydrogen technology
.

The researchers skillfully combined microfabrication techniques and wet chemistry methods to highly selectively regulate the type and number of surface suspension bonds of
silicon nanowire arrays.
Based on the systematic infrared spectrum monitoring, the research team linked the photocatalytic hydrogen production efficiency and the average life of excitons with the surface suspension, thus highlighting the key role
of the surface suspensions of silicon materials in photocatalytic applications.
On the other hand, the researchers found that the ratio of hydrogen and oxygen produced by this process is much higher than the stoichiometry ratio of conventional thinking, so there should be a difference from
the traditional photocatalytic hydrogen production mechanism.
Based on this series of findings, the research team lifted the "veil" of the hydrogen production mechanism of silicon materials by photolysis of water for the first time and determined its reaction mechanism
.
After understanding the mechanism of action, the researchers developed a class of surface chemical treatment methods based on conventional semiconductor industry technology, which provides a simple way to regulate the suspension state located on the surface of silicon nanowires, and rationally modulate its photocatalytic hydrogen production performance
.
(Letter)