Materials Scientists Find New Technique That Could Help Create the Perfect Light-Absorbing Material

James Rondinelli, from the Northwestern University, makes use of quantum mechanical calculations to work at the atom-level of materials. He uses these calculations to anticipate and design the characteristics of new materials.

Rondinelli and his group have been credited with the discovery of a new way to regulate the electronic band gap in highly sophisticated oxide materials. All this has been achieved without changing the overall composition of the material. This finding could potentially help in the development of more improved electro-optical devices (read lasers) and new materials that could either generate energy or convert it from one form to another. Solar cells with heightened absorbency or photoelectrocatalysis with higher sunlight conversion abilities are an example of such materials.

Rondinelli, said that when it comes to collecting the sun’s light, there are no perfect materials. That’s precisely why materials scientists are constantly trying to engineer such a material from scratch. This entails trying to understand the material’s structure, its arrangement of atoms, and how these traits add to or take away from the functionalities and properties of that material.

In the context of light harvesting, conversion and transmission technologies, the electronic band gap is a foundational parameter. Using band-gap engineering, materials scientists can alter the portion in the material to change exactly that portion within a solar spectrum that can be absorbed by solar cells. These factors require that the chemical make-up or structure of the material be changed.

Rondinelli's method is revolutionary in that it can bring about a 200% change to the band gap without causing any modifications to the material’s chemistry.

This research endeavor – supported by the United States Department of Energy (USDE) and the DARPA – has been described in detail in a paper published in the journal Nature Communications. The paper has been co-authored by Prasanna Balachandran, from the New Mexico-based Los Alamos National Laboratory.