In situ heterogeneous OER catalytic reaction study using sum-frequency generation (SFG) spectroscopy
2019 123rd KCS
Abstract: Water oxidation is an essential reaction for energy storage such as forming of hydrogen or hydrocarbons without accumulation of by-product. Unfortunately, This reaction is consist of a complex multistep, which adds a considerably large overpotential to the actual process. Although many studies have been conducted on OER catalysts with low overpotential and high stability, the specific catalytic reaction mechanism has not yet been elucidated. To understand the nature of heterogeneous catalytic reaction mechanism, it is important to use surface/interface selective spectroscopic method. Here, using vibrational sum-frequency generation (VSFG) spectroscopy, we selectively identified electrode-electrolyte interfacial molecules. And we designed spectro-electrochemical (SEC) cell for in situ SFG experiment. In this work, using nonlinear spectroscopic method, we can observe that the hydrogen bonding network of the interfacial water molecules changes at each potential.