Soot’s molecular building-blocks have been glimpsed for the first time.
Soot particles are harmful to humans and the environment. Researchers agree that soot is composed of carbon-based molecules called polycyclic aromatic hydrocarbons, but uncertainty remains about how these molecules look and how they cluster into soot particles.
A team led by Leo Gross at IBM Research–Zurich in Switzerland and Andrea D’Anna at the University of Naples Federico II in Italy examined soot precursors using techniques such as atomic-force microscopy, which produces an ultra-high-resolution topographic map of a sample.
The analysis revealed that many soot precursors contain six-sided chemical structures that look like the cells of a honeycomb. The team also confirmed a previous prediction that soot precursors contain unpaired electrons.
Knowledge about the appearance of soot precursors could help scientists to understand, and potentially prevent, their formation.