We designed an in situ surface-enhanced Raman spectroscopy (SERS) system to detect pH change near the electrode surface. An optically transparent substrate covered with Ag nanoparticles (NPs) that induce SERS was positioned vertically to the electrode. A probe molecule that protonates/deprotonates according to the change in pH of surroundings were distributed nearby the NPs, so that the SERS spectrum of the probe indicated the pH changes in the vertical direction to the electrode due to hydrogen consumption. Flexible choices of probe molecules allow the system to be versatile. The system operated effectively in Ni electrodeposition as a case example.
ASJC Scopus subject areas