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1. Structure-Controlled Oxygen Concentration in Fe ₂ O ₃ and FeO ₂

   https://doi.org/10.1021/acs.inorgchem.8b02764  

   Zhu, Sheng-cai; Liu, Jin; Hu, Qingyang; Mao, Wendy L.; Meng, Yue; Zhang, Dongzhou; Mao, Ho-kwang; Zhu, Qiang (April 2019, Inorganic Chemistry)
2. Oxygen-Induced In Situ Manipulation of the Interlayer Coupling and Exciton Recombination in Bi ₂ Se ₃ /MoS ₂ 2D Heterostructures

   https://doi.org/10.1021/acsami.9b02929  

   Hennighausen, Zachariah; Lane, Christopher; Benabbas, Abdelkrim; Mendez, Kevin; Eggenberger, Monika; Champion, Paul M.; Robinson, Jeremy T.; Bansil, Arun; Kar, Swastik (April 2019, ACS Applied Materials & Interfaces)
3. Strain‐Dependent Activity‐Stability Relations in RuO ₂ and IrO ₂ Oxygen Evolution Catalysts

   https://doi.org/10.1002/celc.202300659  

   Chaudhary, Payal; Zagalskaya, Alexandra; Over, Herbert; Alexandrov, Vitaly (December 2023, ChemElectroChem)

   Abstract Strain engineering is an effective strategy in modulating activity of electrocatalysts, but the effect of strain on electrochemical stability of catalysts remains poorly understood. In this work, we combineab initiothermodynamics and molecular dynamics simulations to examine the role of compressive and tensile strain in the interplay between activity and stability of metal oxides considering RuOand IrOas exemplary catalysts. We reveal that although compressive strain leads to improved activity via the adsorbate‐evolving mechanism of the oxygen evolution reaction, even small strains should substantially destabilize these catalysts promoting dissolution of transition metals. In contrast, our results show that the metal oxides requiring tensile strain to promote their catalytic activity may also benefit from enhanced stability. Importantly, we also find that the detrimental effect of strain on electrochemical stability of atomically flat surfaces could be even greater than that of surface defects. 

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4. CO ₂ -driven and orbitally driven oxygen isotope variability in the Early Eocene

   https://doi.org/10.5194/cp-20-495-2024  

   Campbell, Julia; Poulsen, Christopher J; Zhu, Jiang; Tierney, Jessica E; Keeler, Jeremy (January 2024, Climate of the Past)

   Abstract. Paleoclimate reconstructions of the Early Eocene provide important data constraints on the climate and hydrologic cycle under extreme warm conditions. Available terrestrial water isotope records have been primarily interpreted to signal an enhanced hydrologic cycle in the Early Eocene associated with large-scale warming induced by high atmospheric CO2. However, orbital-scale variations in these isotope records have been difficult to quantify and largely overlooked, even though orbitally driven changes in solar irradiance can impact temperature and the hydrologic cycle. In this study, we fill this gap using water isotope–climate simulations to investigate the orbital sensitivity of Earth's hydrologic cycle under different CO2 background states. We analyze the relative difference between climatic changes resulting from CO2 and orbital changes and find that the seasonal climate responses to orbital changes are larger than CO2-driven changes in several regions. Using terrestrial δ18O and δ2H records from the Paleocene–Eocene Thermal Maximum (PETM), we compare our modeled isotopic seasonal range to fossil evidence and find approximate agreement between empirical and simulated isotopic compositions. The limitations surrounding the equilibrated snapshot simulations of this transient event and empirical data include timing and time interval discrepancies between model and data, the preservation state of the proxy, analytical uncertainty, the relationship between δ18O or δ2H and environmental context, and vegetation uncertainties within the simulations. In spite of the limitations, this study illustrates the utility of fully coupled, isotope-enabled climate models when comparing climatic changes and interpreting proxy records in times of extreme warmth. 

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5. Mechanism and Kinetics of Na ₂ S _x (x ≤ 2) Precipitation in Sodium-Sulfur and Sodium/(Oxygen)-Sulfur Batteries

   https://doi.org/10.1149/1945-7111/ad14cb  

   Zhang, Qipeng; Yang, Tairan; Li, Zheng (January 2024, Journal of The Electrochemical Society)

   Room-temperature sodium-sulfur (RT Na-S) batteries have attracted ever-increasing attention because of their enhanced energy density and low price. Although the performance of RT Na-S batteries is obtained in many other research, the basic mechanism and kinetics have not involved yet, especially in discharge product growth, which affects electrochemical performance. Meanwhile, designed additional redox activities (in the presence of oxygen) could simultaneously suppress sodium polysulfide shuttling and enhance energy density according to our group reported. However, the kinetic study of the intermediate has not been explored. In this work, we discussed the deposition of low-order sodium polysulfide (Na₂S_x, x ≤ 2) in different potentials and types of glyme-solvents in Na-S and Na/(O₂)-S system. The results show that the morphology of deposition Na₂S_x(x ≤ 2) is affected by interfacial energy barrier controlled by overpotentials and the radius of sodium ions, which produced the precipitation of particle shape rather than film. Potentiostatic experiments show the kinetics are elevated in the presence of oxygen. In addition, the exchange current density of different sodium polysulfides was studied. The high-order sodium polysulfide has a lower exchange current density than that of low-order sodium polysulfide in Na-S system, requiring greater driving force, while transformation of the intermediate from high-order oxy-sulfur to low-order oxy-sulfur species require less impulse in Na/(O₂)-S systems. This paper provides new understandings of the deposition mechanism and kinetics of Na₂S_x(x ≤ 2) Na-S and Na/(O₂)-S system in and to choose the appropriate solvent and potential. 

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