Electrostatic charges and their distribution on the charged surfaces probed by sum-frequency generation spectroscopy

We examined the electrostatic charging states of insulating polymer surfaces using sum-frequency generation (SFG) spectroscopy. For the negatively charged polypropylene, the SFG peak amplitudes increased significantly with increasing surface potential, indicating that the electric-field formed by the electrostatic charges directly affects the SFG signal intensities. In the organic thin films stacked on top of PMMA, an increase in the SFG signal of buried PMMA is observed, indicating that the electrostatic field formed by the electrical charges is extended into the bulk direction. In addition, visualization of the location and distribution of the charges is demonstrated using the SFG intensity variations.

Automated summary

The electrostatic charging states of insulating polymer surfaces were analyzed using sum-frequency generation (SFG) spectroscopy. For negatively charged polypropylene, the SFG peak amplitudes increased significantly with increasing surface potential, indicating a direct influence of the electrostatic charges on the SFG signal intensities. In organic thin films stacked on top of PMMA, an increase in the SFG signal of buried PMMA was observed, indicating the extension of the electrostatic field into the bulk direction. Additionally, the visualization of charge location and distribution was demonstrated using SFG intensity variations.