Paper SS-TuP3
Revealing the Atomic Scale Insights for CO₂ Dissociation on the Rh(111) Surfaces at Ambient Pressure

Tuesday, October 23, 2018, 6:30 pm, Room Hall B

Carbon dioxide (CO₂) in the atmosphere is one of the main cause of the greenhouse effect due to CO₂ molecules absorb the infrared radiation emitted by the Earth’s surface. Since the Industrial Revolution in 1750’s, the concentration of CO₂ in the atmosphere is continuously increased owing to increase of its emission in the economic sector such as electricity and heat production, industry, transport, and etc. Therefore, the utilization of CO₂ has received great attention from many researchers because of the challenging issue to use CO₂ as an energy resource.

A fully oxidized form of carbon e.g. CO₂, however, is a very stable compound which has two double bonds between carbon (C) and oxygen (O) in opposite direction. To facilitate the CO₂ utilization, as the first step of the reaction, the bond between C and O need to weaken or broken for further reactions. Rhodium is well known reducing material which can offer its electrons to the reactants. Previous research on CO₂ reduction reaction showing that CO₂ molecules have a bent structure or CO₃^2- after they adsorbed on a catalyst surface by using vibrational and spectroscopies such as IRARS and XPS. However, there is no direct observation for the bent structure of CO₂ on the catalyst surface. Here, we will show the first atomic-scale observation of bent CO₂ adsorption on Rh(111) surface as an intermediate by using near ambient pressure scanning tunneling microscope (NAP-STM). Furthermore, we will discuss the possible mechanism of CO₂ dissociation on Rh(111) based on the NAP-STM images of CO and O₂ adsorption structures on Rh(111) at NAP conditions.