Reversible Ultrathin PtO_x Formation at the Buried Pt/YSZ(111) Interface Studied In Situ under Electrochemical Polarization

Abstract

Three different platinum oxides are observed by in situ X-ray diffraction during electrochemical potential cycles of platinum thin film model electrodes on yttria-stabilized zirconia (YSZ) at a temperature of 702 K in air. Scanning electron microscopy and atomic force microscopy performed before and after the in situ electrochemical X-ray experiments indicate that approximately 20% of the platinum electrode has locally delaminated from the substrate by forming pyramidlike blisters. The oxides and their locations are identified as (1) an ultrathin PtO x at the buried Pt/YSZ interface, which forms reversibly upon anodic polarization; (2) polycrystalline β-PtO 2 , which forms irreversibly upon anodic polarization on the inside of the blisters; and (3) an ultrathin α-PtO 2 at the Pt/air interface, which forms by thermal oxidation and which does not depend on the electrochemical polarization. Thermodynamic and kinetic aspects are discussed to explain the coexistence of multiple phases at the same electrochemical conditions.

Exploring the Bifunctionality of YSZ Thin Films in MOS Structures: Bridging the Gap between RRAM and Super-Pseudocapacitor Technologies

“…The phenomenon of electrode blistering has been extensively studied in both RS , and energy storage devices. − Interfacial reactions between the electrode material and the electrolyte are the primary cause of blister formation. Specifically, the reaction generates gas bubbles (in this case molecular oxygen) that accumulate at the electrode–electrolyte interface and exert pressure on the electrode leading to delamination.…”

Anode Process on Platinum in Low Temperature KF-AlF3-Al2O3 Based Melts: An Update

“…Thus, at the initial time after replacing the atmosphere in the retort with oxygen, the measured potential difference (0.75-0.78 V) is close to the thermodynamic value. The increase in the potential difference during further purging of the quartz retort with oxygen can be explained by the adsorption of oxygen atoms on Pt 35,36 and the formation of stable Pt x O oxides at the measurement temperature. 36,37 As a result, oxygen supersaturation or a change in the function of oxygen electrode may occur.…”

“…The increase in the potential difference during further purging of the quartz retort with oxygen can be explained by the adsorption of oxygen atoms on Pt 35,36 and the formation of stable Pt x O oxides at the measurement temperature. 36,37 As a result, oxygen supersaturation or a change in the function of oxygen electrode may occur.…”