Publications by Dimitra Anastasiadou
Papers by Dimitra Anastasiadou
This manuscript reports the simultaneous electrodeposition of Cu and Rh from an aqueous nitrate s... more This manuscript reports the simultaneous electrodeposition of Cu and Rh from an aqueous nitrate solution. The early stages of nucleation and growth of the bimetallic layer were explored using techniques such as cyclic voltammetry and current transients. Non-dimensional Scharifker–Hills graphs showed the occurrence of diffusion-controlled three-dimensional nucleation and growth best described by the Volmer-Weber mechanism. Additionally, different ratios of Cu-Rh catalysts were synthesized by varying the potential of deposition and the Rh content in the deposition bath. Characterization techniques including electron microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy were employed to investigate the chemical composition and structure of the deposits. The results showed a higher amount of Cu2+ species in the layer than Cu+/Cu0 when a more negative potential was applied, and when Rh was present in high amounts in the deposition bath The final morphology of the obtained c...
Chemical Communications, 2020
This article presents the latest research on electrosynthesis routes to organic carbonates. Diffe... more This article presents the latest research on electrosynthesis routes to organic carbonates. Different methods are discussed in an effort to understand the underlying processes and challenges.
Catalysis Science & Technology, 2020
The interaction of In and Pd in bimetallic particles causes dramatic changes in the CO2 reduction... more The interaction of In and Pd in bimetallic particles causes dramatic changes in the CO2 reduction behavior.
ChemElectroChem, 2019
Novel electrodes for the electroreduction of CO 2 were prepared by the electrodeposition of coppe... more Novel electrodes for the electroreduction of CO 2 were prepared by the electrodeposition of copper (I) oxide (Cu 2 O) catalytic films on a gas diffusion layer. Different electrodes were prepared by varying the deposition time, corresponding to catalyst loadings of 0.37, 0.74, 2.22, 3.70 mg cm À 2 and a total charge density of 0.5, 1, 3, and 5 C cm À 2 , respectively. The electrodes were characterized with SEM, XRD, and UPD. The effect of catalyst loading on the selectivity towards ethylene was investigated in an alkaline flow electrolyzer under ambient conditions. The electrodes were found to be highly selective (> 60 %) towards ethylene. The 1 C cm À 2 electrode reached Faradaic efficiency values as high as 67 % at industrially relevant current densities of 183 mA cm À 2 , À 0.8 V cathode overpotential and 36 % cell energy efficiency. This performance was attributed to the interplaying role of applied potential, local pH, availability of active sites, and reduced CO 2 mass transport limitations.
ACS Applied Materials & Interfaces, 2018
Cathodic corrosion is an electrochemical etching process that alters metallic surfaces by creatin... more Cathodic corrosion is an electrochemical etching process that alters metallic surfaces by creating nanoparticles and a variety of etching features. Because these features typically have a preferential orientation, cathodic corrosion can be applied to modify and nanostructure electrode surfaces. However, this application of cathodic corrosion is currently limited by an insufficient chemical understanding of its underlying mechanism. This includes the role of alkali metal cations, which are thought to be crucial in both enabling cathodic corrosion and controlling its final facet preference. This work addresses this knowledge gap by exploring the cathodic corrosion of Pt, Rh, and Au in LiOH, NaOH, and KOH through both experimental and theoretical methods. These methods demonstrate that cations are adsorbed during cathodic corrosion and play a major role in controlling the onset potential and final surface morphology in cathodic corrosion. Interestingly, an equally significant role appears to be played by adsorbed hydrogen, based on calculations using literature density functional theory data. Considering the significance of both hydrogen and electrolyte cations, it is hypothesized that cathodic corrosion might proceed via an intermediate ternary metal hydride. This fundamental insight leads to both metal-specific recommendations and more general guidelines for applying cathodic corrosion to structure metallic surfaces.
This manuscript reports the electrosynthesis of ammonia from nitrate catalysed by Cu2O. Cu2O (111... more This manuscript reports the electrosynthesis of ammonia from nitrate catalysed by Cu2O. Cu2O (111) and (100) preferential orientations were prepared through electrodeposition to investigate the effect of surface structure. Cu2O (111) is more active and selective for ammonia formation than Cu2O (100). The highest faradaic efficiency (FE) was achieved for both catalysts at -0.3 V vs RHE, with Cu2O (111) reaching up to 80%. Additional measurements with quasi-in situ X-ray photoelectron spectroscopy and in-situ Raman spectroscopy revealed that Cu0 is the active phase during the reaction. The stability of the catalysts was examined by ex-situ methods such as scanning electron microscopy, X-ray diffraction and inductively coupled plasma-optical emission spectrometry. The catalysts undergo severe morphological changes as a function of the applied potential and the reaction time, most likely due to the dissolution and redeposition of Cu. After three hours of reaction, the entire surface of ...
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Publications by Dimitra Anastasiadou
Papers by Dimitra Anastasiadou