A research team led by Professor Yang Liangbao from the Hefei Institute of Physical Sciences of the Chinese Academy of Sciences (CAS) observed the interaction between aromatic molecules and Au surfaces on a single Au nanodimer using surface-enhanced Raman spectroscopy (SERS). The study was published on: Analytical chemistry It was chosen as the first cover of the issue.

The interaction interface between aromatic molecules and noble metals has an important place in basic science and technological applications. However, due to the limitations of the characterization technology and the complexity of the experimental conditions, a quantitative understanding of the specific mechanism of this interaction under environmental conditions is still lacking.

To solve this problem, the research team created a nanodimer structure of Au with a subnanometer gap. Based on this structure, scientists obtained information about the spectrum of surface molecular vibrations using SERS.

Using the same structure, they also achieved highly sensitive SERS detection of polycyclic aromatic hydrocarbons (PAHs). They found that the SERS sensitivity of PAHs increased as the number of aromatic rings in the molecule increased. This provides a new idea for highly sensitive detection of aromatic molecules.

At the same time, the physical adsorption types of aromatic molecules on the Au surface and the distribution of electron density at the interface were revealed. This work demonstrates the great potential of SERS in interfacial interaction studies at the single-molecule level and also provides new implications for fundamental research and technical applications in related fields.