Abstract
The electrochemical noise (ECN) technique was employed to study corrosion of two model systems, i.e. pure Ni and a binary Ni-20 wt%Cr (Ni20Cr) alloy in molten ZnCl2 at 623 K. We measured ECN transients in current and open-circuit potential from two nominally identical Ni-Ni and Ni20Cr-Ni20Cr electrodes and one galvanic Ni-Ni20Cr electrode pair. The behavior of ECN is quite distinct among the three-electrode systems, and it is correlated with the various microscopic observations of micro- and nano-scale morphological features. Based on the ECN study coupled with the microstructural analysis, the origins of ECN in the molten salt environment as well as the mechanisms of localized corrosion in the three systems are discussed.
| Original language | English |
|---|---|
| Article number | 141126 |
| Journal | Electrochimica Acta |
| Volume | 431 |
| DOIs | |
| State | Published - Nov 1 2022 |
Funding
This work was supported as part of the Molten Salts in Extreme Environments Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science. Brookhaven National Laboratory (BNL), Idaho National Laboratory (INL), and Oak Ridge National Laboratory are operated under DOE contracts DE-SC0012704, DE-AC07–05ID14517, and DE-AC05–00OR22725, respectively. This research used resources of the Center for Functional Nanomaterials, which is a U.S. DOE Office of Science Facility, at Brookhaven National Laboratory. L. He also acknowledges the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07–05ID14517, for use of the resources as part of Nuclear Science User Facilities. The authors thank Bobby Layne at the BNL Chemistry Division, and Megha Dubey, Jatuporn Burns, Yaqiao Wu, and Kristi Moser-McIntire at the INL Center for Advanced Energy Studies, and Miles Cook, Jayson Bush, Jeffery Bailey, and JoAnn Merrill at INL for their invaluable assistance. This work was supported as part of the Molten Salts in Extreme Environments Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science. Brookhaven National Laboratory (BNL), Idaho National Laboratory (INL), and Oak Ridge National Laboratory are operated under DOE contracts DE-SC0012704 , DE-AC07–05ID14517 , and DE-AC05–00OR22725 , respectively. This research used resources of the Center for Functional Nanomaterials, which is a U.S. DOE Office of Science Facility, at Brookhaven National Laboratory. L. He also acknowledges the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07–05ID14517 , for use of the resources as part of Nuclear Science User Facilities. The authors thank Bobby Layne at the BNL Chemistry Division, and Megha Dubey, Jatuporn Burns, Yaqiao Wu, and Kristi Moser-McIntire at the INL Center for Advanced Energy Studies, and Miles Cook, Jayson Bush, Jeffery Bailey, and JoAnn Merrill at INL for their invaluable assistance.
Keywords
- Electrochemical noise
- Intergranular corrosion
- Molten salt
- Nickel-chromium
- Pitting