New class of optoelectronic materials

Currently, the most useful semiconductors don't hold enough carriers for a given volume of material, but have high mobility. The real challenge for scientists has been to increase the density of states in materials, while maintaining high mobility.

The proposed material is predicted to possess both properties. The researchers have called this class of semiconductors: ‘transition metal perovskite chalcogenides’.

As a first step, the researchers studied its ability to absorb and emit light. "There is a saying," says assistant professor Jayakanth Ravichandran, "that a good LED is also a good solar cell."

Since the materials the team developed absorb and emit light effectively, solar cells are a possible application. According to the group, the next step is to recreate this material in an ultra-thin film form to make solar cells and test their performance.

"The key contribution of this work is our new synthesis method, which is a drastic improvement from earlier studies," concludes Ravichandran. "Also, our demonstration of wide tunability in optical properties – especially band gap – is promising for developing new optoelectronic devices with tuneable optical properties."