New insights into light harvesting boost for solar future

A new promising approach in understanding the basic mechanisms of light harvesting could help improve the design and efficiency of devices like solar cells in the future.

With the new technique, the scientists were able to understand how the same molecular machinery can perform efficient light harvesting at low light while safely dissipating excess excitation energy at high light.

Studying various photosynthetic antenna proteins using the single-molecule Anti-Brownian ELectrokinetic (ABEL) trap, scientists uncovered new states of the light harvesting complexes with different degrees of quenching.

"By analysing the transition between these states in a bacterial antenna protein, we found a process that may be one of the molecular mechanisms of photoprotection, or the way in which the organism protects itself from damage by excess light," explained Hsiang-Yu Yang from W.E. Moerner's research group at Stanford University.

Light harvesting enables photosynthetic organisms to thrive even as weather conditions change from full sunlight to deep cloud cover.

The next steps are to use this technique to understand the natural designs of light harvesting systems and investigate whether the same processes appear in higher plants.

"We are extending studies to look at photosynthetic proteins from green plants.

"Eventually, understanding these general principles may help in developing or improving the building of artificial light-harvesting devices," the researchers noted.