The development of highly active and durable CO2 methanation catalysts remains a major challenge, particularly because catalyst restructuring and sintering of the active particles can progressively reduce catalytic performance. Exsolved perovskite-derived catalysts have therefore attracted growing interest due to their ability to generate strongly anchored metallic nanoparticles with enhanced metal–support interactions and stability. However, conventional perovskite synthesis methods generally produce low-surface-area materials, limiting the accessibility of active sites and their catalytic performance. Here, a high-surface-area LaNiO3 perovskite was synthesized by a nanocasting approach using SBA-15 as a hard template and investigated as a precursor for exsolved Ni/LaOx catalysts for CO2 methanation. Reduction under H2 led to the exsolution of metallic Ni nanoparticles with average sizes below 6 nm and a narrow particle-size distribution. The reduction temperature has a clear influence on the CO2 methanation performance, with the catalyst reduced at 600 °C exhibiting the highest activity, nearly complete CH4 selectivity, and excellent stability over 65 h on stream. In situ surface-sensitive spectroscopy measurements revealed that H2 reduction induces partial encapsulation of Ni nanoparticles by lanthanum oxide species within the outermost few nanometers of the catalyst surface. Under CO2 methanation conditions, however, the catalyst dynamically restructures, progressively driving Ni back toward the surface. This reversible Ni segregation correlates with the formation of surface carbonate species, suggesting that adsorbate-induced restructuring governs the active interfacial state. These findings demonstrate that the active phase for CO2 methanation over LaNiO3-derived catalysts is a dynamically reconstructed Ni–LaOx interface controlled by the gas-phase environment, highlighting the central role of surface restructuring in the performance of exsolved perovskite-derived catalysts.

Discovered almost 130 years ago by P. Sabatier, CO2 hydrogenation to methane (CO2 methanation) is presently attracting attention as one of the most promising methods for storing intermittent renewable energy in the form of chemical fuels. Ni particles supported by CeO2 constitute a very effective, reliable, and reasonably priced catalyst for CO2 methanation. Recently a new type of CO2 methanation catalyst, consisting of cerium oxide (ceria) nanoparticles doped with nickel (NiCeOx) in a specific square‐planar configuration with an extremely high‐Ni mass‐specific activity and almost 100% CH4 selectivity, was reported. Here, a 50% enhancement in the CO2 conversion of the NiCeOx catalyst by carefully adjusting the calcination temperature is demonstrated. Notably, thermal aging at 600 °C enhances methanation performance by partially exsolving Ni to the surface, while higher temperatures (750 °C) lead to larger Ni particles, increased CO production, and surface carbon deposition. Several in situ and operando characterization methods are employed to correlate the thermal activation and deactivation of the catalyst with its nanoscale characteristics. Apart from their clear implications for the design of next‐generation Ni‐based CO2 methanation catalysts, these findings significantly enhance understanding of the complex interplay and nature of various surface sites involved in CO2 hydrogenation.

Thin film (Ag,Cu)(In,Ga)(SSe)2 has promising potential applications as a top cell in tandem solar cell devices. The chalcopyrite film must be deposited on a transparent back contact (TBC) for such applications, and therefore the well-established back contact structure must be re-examined and reoptimized. In this contribution, we examine the formation of gallium oxide interface species and the impact of process variables on the resulting chemical and electronic structure. By cleaving the absorber/TBC layer stack, the backside of the absorber and the exposed TBC can be made accessible to be characterized by surface-sensitive energy dependent X-ray photoelectron spectroscopy (XPS). Significant changes in the thickness of the oxide layers were revealed as a function of absorber Ga content, Na content, and other variables related to synthesis. The link between oxide properties and device performance will be discussed.

Supported catalytically active liquid metal solutions (SCALMS) are materials composed of a liquid metal alloy deposited on a porous support. Due to the dynamic properties of the liquid metal alloy, these systems are suggested to form single atom sites, resulting in unique catalytic properties. Ga-Ni SCALMS were successfully applied to ethylene oligomerization, yielding catalysts that were stable up to 120 h time on stream. A workflow based on synchrotron-based X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) as well as density function theory (DFT) and ab initio molecular dynamics (AIMD) simulations was applied to investigate the nature of the active species in these materials. The combination of XPS with DFT calculations indeed indicates the presence of isolated single Ni atoms on the liquid metal surface, while TEM measurements show high dynamics in the liquid metal with intermetallic phase dissolution and transformation. Furthermore, DFT/AIMD methods allowed for rationalizing the role of hydrogen pretreatment in enriching the Ni atom at the surface of the liquid metal alloy.

Electrochemical cation intercalation into 2D NiPS 3 leads either to reduction of the (P 2 S 6 ) 4− units (Li example) or Ni cations (Na example), or causes electrochemical reduction and decomposition of EMIM cations within the van der Waals interlayers.

Understanding the oxygen evolution reaction (OER) and Ir dissolution mechanisms in amorphous, hydrous iridium oxides (am-hydr-IrOx) is hindered by the reliance on crystalline iridium oxide theoretical models to interpret its behaviour. This study presents a comprehensive investigation of hydrous iridium oxide thin films (HIROFs) as a model for am-hydr-IrOx to elucidate electronic and structural transformations under OER conditions of proton exchange membrane water electrolyzers (PEM-WE). Employing in situ and operando Ir L3-edge X-ray absorption spectroscopy supported by density functional theory calculations, we introduce a novel surface H-terminated nanosheet model that better characterizes the short-range structure of am-hydr-IrOx compared to previous crystalline models, which exhibits elongated Ir-O bond lengths compared to rutile-IrO2. This atomic model unveils the electronic and structural transformations of am-hydr-IrOx, progressing from H-terminated nanosheets to structures with multiple Ir vacancies and shorter bond-lengths at OER potentials. Notably, Ir dissolution emerges as a spontaneous, thermodynamically driven process, initiated at potentials lower than OER activation, which requires a parallel mechanistic framework describing Ir dissolution by Ir defect formation. Moreover, our results provide mechanistic insights into the activity-stability relationship of am-hydr-IrOx by systematically screening the DFT-calculated OER activity of diverse Ir and O chemical environments. This work challenges conventional perceptions of iridium dissolution and OER mechanisms in am-hydr-IrOx, providing an alternative perspective within a dual-mechanistic framework.

Abstract Future carbon management strategies require storage in elemental form, achievable through a sequence of CO2 hydrogenation reactions. Hydrogen is recycled from molecular intermediates by dehydrogenation, and side product acetylene selectively hydrogenated to ethylene. Existing Pd alloy catalysts for gas purification underperform in concentrated feeds, necessitating novel concepts. Atomistic simulations unveil superior selectivity of Pd:C solid solutions that optimize chemisorption energies and preclude sub-surface hydrides, verified here with model thin films. Multiple design criteria deduced from conventional catalysts facilitate synthesizing a self-repairing Pd:C system of a laterally condensed catalyst (LCC). A Pd layer prepared on a designated SiO2 buffer layer enables control of reactive interface, sub-surface volume and extended functional interface towards the buffer. Function and metric are supervised by operando micro-spectroscopy. This catalyst design shows, ethylene productivity >1 kmolC2H4/gPd/hour is reproducibly achieved and benchmarked against known catalysts. Photovoltaics deposition technologies enable scalability on real-world substrates saving active metal. A design-of-experiment approach demonstrates the improvement potential of the LCC approach.

In situ tender X-ray absorption near-edge structure (XANES) spectroscopy at the P K-edge was utilized to investigate the oxidation mechanism of aqueous H3PO3 on Pt electrodes under various conditions relevant to high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) applications. XANES and electrochemical analysis were conducted under different tender X-ray irradiation doses, revealing that intense radiation induces the oxidation of aqueous H3PO3 via H2O yielding H3PO4 and H2. A broadly applicable experimental procedure was successfully developed to suppress these undesirable radiation-induced effects, enabling a more accurate determination of the aqueous H3PO3 oxidation mechanism. In situ XANES studies of aqueous 5 mol dm-3 H3PO3 on electrodes with varying Pt availability and surface roughness reveal that Pt catalyzes the oxidation of aqueous H3PO3 to H3PO4. This oxidation is enhanced upon applying a positive potential to the Pt electrode or raising the electrolyte temperature, the latter being corroborated by complementary ion-exchange chromatography measurements. Notably, all of these oxidation processes involve reactions with H2O, as further supported by XANES measurements of aqueous H3PO3 of different concentrations, showing a more pronounced oxidation in electrolytes with a higher H2O content. The significant role of water in the oxidation of H3PO3 to H3PO4 supports the reaction mechanisms proposed for various chemical processes observed in this work and provides valuable insights into potential strategies to mitigate Pt catalyst poisoning by H3PO3 during HT-PEMFC operation.

Metal-support interactions, which are essential for the design of supported metal catalysts, used, e.g., for CO2 activation, are still only partially understood. In this study of gold-loaded In2O3 and CeO2 catalysts during CO2 hydrogenation using near-ambient pressure X-ray photoelectron spectroscopy, supported by near edge X-ray absorption fine structure, we demonstrate that the role of the noble metal strongly depends upon the choice of the support material. Temperature-dependent analyses of X-ray photoelectron spectra under reaction conditions reveal that gold is reduced on CeO2, enabling direct H2 activation, but oxidized on In2O3, leading to decreased activity of Au/In2O3 compared to bare In2O3. At elevated temperatures, the catalytic activity of the In2O3 catalysts strongly increases as a result of facilitated CO2 and (In2O3-based) H2 activation, while the catalytic activity of Au/CeO2 is limited by reoxidation by CO2. Our results underline the importance of operando studies for understanding metal-support interactions to enable a rational support selection in the future.

CO2 methanation, also known as the Sabatier reaction, is of great environmental interest as a sustainable process for energy production and storage. Herein, we report the development of a Ni-La2O3 catalyst for CO2 methanation prepared upon reduction of a LaNiO3 perovskite precursor. The perovskite-based catalyst exhibits enhanced activity, high methane selectivity and improved stability when compared to Ni-La2O3 prepared through conventional impregnation methods. The transformation of the LaNiO3 perovskite precursor upon thermal activation in H-2 was found to have a profound impact on the catalytic properties of the resulting material. The size and stability of exsolved Ni nanoparticles after prolonged reaction were investigated using ex situ electron microscopy. Synchrotron-based X-ray absorption fine structure (XAFS) spectroscopy, as well as soft and tender X-ray photoelectron spectroscopies (AP-XPS/HAXPES), provides detailed insights into the evolution of bulk and surface phases during the transition of the perovskite to its active catalytic state. Our findings indicate that processes beyond the well-established exsolution of nanoparticles, such as lanthana spillover onto nickel, may occur during H-2 activation. More importantly, in situ spectroscopy under CO2 methanation conditions revealed that the surface's affinity for La-hydroxide or La-carbonate formation significantly influences the reactivity. Specifically, we found that La-hydroxide acts as a precursor for the formation of La-oxycarbonate (hexagonal La2O2CO3 phase), a crucial element of the active exsolved catalyst. In contrast, in the absence of La-hydroxide, La-carbonates (La-2(CO3)(3)) formed on the surface, blocking the active sites of the supported catalyst. Our research examines hitherto unrecognized processes affecting the reactivity of exsolved perovskites, highlighting LaNiO3 as a promising catalyst for CO2 methanation.

Nickel/yttria-stabilized zirconia (YSZ) composites are the most commonly used fuel electrodes for solid oxide cells. While microstructural changes of Ni/YSZ during operational conditions have been thoroughly investigated, there is limited knowledge regarding Ni/YSZ surface chemistry under working conditions. In this study, we examine the interaction between Ni/YSZ electrodes and water vapor under open circuit and polarization conditions, utilizing near ambient pressure soft and hard X-ray photoelectron spectroscopies. Miniature cells with conventional porous Ni/YSZ composite cermet cathodes were modified to facilitate the direct spectroscopic observation of the functional electrode's areas close to the interface with the YSZ electrolyte. The results highlight dynamic changes in the oxidation state and composition of Ni/YSZ under H2 and H2O atmospheres. We also quantify the accumulation of impurities on the electrode surface. Through adjustments in the pretreatment of the cell, the correlation between the nickel surface oxidation state and the cell's electrochemical performance during H2O electroreduction is established. It is unequivocally shown that nickel surface oxidation in H2O electrolysis favors NiO over Ni(OH)x, providing critical insights into the mechanism of Ni-phase redistribution within the electrode during long-term operation. Depth-dependent photoemission measurements, combined with theoretical quantitative simulations, reveal that NiO and Ni phases are uniformly mixed on the surface during H2O electrolysis. This differs from the conventional expectation of a NiO-shell/Ni-core configuration in gas phase oxidation. These findings provide crucial insights into the surface chemistry of Ni/YSZ electrodes under conditions relevant to H2O electrolysis, elucidating their impact on the electrochemical performance of the cell.

High-temperature electrolyte membrane fuel cells (HT-PEMFCs) using H 3 PO 4 -doped membranes are an enticing choice for electrochemical energy sources at elevated temperatures [1]. Yet, one of the challenges concerning these systems is the reduction of H 3 PO 4 to lower valency phosphorus compounds, such as H 3 PO 3 , during operation [2,3,4]. H 3 PO 3 can strongly adsorb on the Pt catalysts, hence poisoning it and thereby lowering the fuel cell performance [5,6]. Interestingly, the presence of Pt may, under certain conditions, catalyze the chemical (re-)oxidation of aqueous H 3 PO 3 back to H 3 PO 4 , illustrating the complexity of the H 3 PO x – Pt interaction. Therefore, to optimize the performance of HT-PEMFCs by rational design of the catalyst/electrolyte interface, further insight into H 3 PO 3 oxidation behaviour and Pt/H 3 PO 3 interaction under conditions relevant to HT-PEMFCs operation is required. In this study, in situ P K - edge XANES (x-ray absorption near edge structure) spectroscopy was conducted to shed light on the oxidation behaviour of aqueous H 3 PO 3 by investigating the impact of (i) different temperatures (25°C vs 75°C), (ii) varying electrode roughness (flat planar Pt vs rough Pt black), (iii) different electrode potentials (open circuit potentials vs more positive potentials [+0.8, +0.9, and +1.0 V RHE ]), and (iv) varying molar concentrations of H 3 PO 3 (0.1 , 1 , and 5 mol dm -3 ). Initially, XANES coupled with electrochemical characterization (e.g. OCP, cyclic voltammetry) of the system was performed under different radiation doses (i.e.: photon fluxes, exposure time) to determine the effect of radiolysis and/or radiation damage during experiments that may lead to misinterpretations of XANES results. Under high radiation dose, we find evidence of H 2 presence in the vicinity of the Pt electrode, likely generated by water radiolysis. We have developed experimental procedures to suppress these undesirable effects during the collection of the XANES data, enabling an accurate determination of H 3 PO 3 oxidation behaviour and minimizing the radiolysis contribution to the process. It was found that higher temperature facilitates the oxidation of aqueous H 3 PO 3 to H 3 PO 4 , presumably because H 3 PO 3 exists in the thermodynamically preferred “active” pyramidal form at elevated temperatures, which is more prone to react with H 2 O, forming H 3 PO 4 and H 2 . In aqueous H 3 PO 3 solutions with higher H 2 O contents, also more pronounced oxidation of H 3 PO 3 is observed, indicating that oxidation of H 3 PO 3 to H 3 PO 4 in aqueous solutions proceeds via the presence of H 2 O. The experiments using rough Pt black electrodes additionally hint at the observation of electrochemical oxidation of H 3 PO 3 to H 3 PO 4 during the application of positive potentials. This work provides insights into the underlying chemical processes that occur at conditions relevant for HT-PEMFCs operation and thus it paves the way for possible strategies to mitigate H 3 PO 3 poisoning of the Pt electrode during operation. References: [1] Chandan et al. J. Power Sources 2013 , 231 , 264–278. [2] Sugishima et al. J. Electrochem. Soc. 1994 , 141 (12), 3332. [3] Doh et al. ChemElectroChem 2014 , 1 (1), 180–186. [4] Prokop et al. Electrochim. Acta 2015 , 160 , 214–218. [5] Gomes et al. J. Electroanal. Chem. 2022 , 918 , 116450. [6] Gomes et al. ACS Catal. 2022 , 12 (18), 11472 11484 Figure 1

The interaction between metal particles and the oxide support, the so-called metal–support interaction, plays a critical role in the performance of heterogenous catalysts. Probing the dynamic evolution of these interactions under reactive gas atmospheres is crucial to comprehending the structure–performance relationship and eventually designing new catalysts with enhanced properties. Cobalt supported on TiO2 (Co/TiO2) is an industrially relevant catalyst applied in Fischer−Tropsch synthesis. Although it is widely acknowledged that Co/TiO2 is restructured during the reaction process, little is known about the impact of the specific gas phase environment at the material’s surface. The combination of soft and hard X-ray photoemission spectroscopies are used to investigate in situ Co particles supported on pure and NaBH4-modified TiO2 under H2, O2, and CO2:H2 gas atmospheres. The combination of soft and hard X-ray photoemission methods, which allows for simultaneous probing of the chemical composition of surface and subsurface layers, is one of the study’s unique features. It is shown that under H2, cobalt particles are encapsulated below a stoichiometric TiO2 layer. This arrangement is preserved under CO2 hydrogenation conditions (i.e., CO2:H2), but changes rapidly upon exposure to O2. The pretreatment of the TiO2 support with NaBH4 affects the surface mobility and prevents TiO2 spillover onto Co particles.

Currently, only iridium oxide shows favourable activity and stability under the harsh oxygen evolution reaction (OER) conditions for application in proton exchange membrane water electrolysis (PEM-WE) [1-3]. There is a well established inverse relationship between OER activity and stability of iridium oxide-based OER catalysts given its degree of crystallinity and hydration [4-6]. Crystalline, anhydrous iridium oxides are more stable but have diminished OER activity compared to amorphous, hydrous iridium oxides, which are more active. Different OER mechanisms have been theorized to occur on these materials, explaining their difference in performance [6]. Several spectroscopic investigations have been performed to explore the properties of such different iridium oxides, in particular to identify the chemical and electronic state of their active sites. However, a consensus regarding the active site structure and OER mechanism has yet to be reached [7-10]. Using scanning electron microscopy, x-ray photoelectron spectroscopy, and combining in-situ Ir L 3-edge x-ray absorption spectroscopy with density functional theory (DFT) calculations and ab initio thermodynamics, we have investigated in-situ electrochemically grown porous hydrous iridium oxide thin films (HIROF) as a model system to examine the chemical and electronic structure of the highly active, hydrous iridium oxide species. In-situ extended x-ray absorption fine structure(EXAFS) results show that HIROF grows preferentially in a form most often associated with the OER catalytically active site of hydrous iridium oxides. Calculations over different possible structures allowed us to identify a unique structural group with enhanced hydrogenation that best fits the EXAFS data. In-situ x-ray absorption near edge structure (XANES) results reveal a lower onset potential for the redox behaviour of HIROF compared to rutile IrO2. Based on this study, we propose a new structural model explaining the high activity and poorer stability of hydrous iridium oxides compared to crystalline IrO2. References: [1] A. Buttler and H. Spliethoff, Renew. Sustain. Energy Rev., 2018, 82, pp. 2440-2454. [2] Schlögl, ChemSusChem, 2010, 3, pp. 209-222. [3] M. Schalenbach, J. Electrochem. Soc., 2016, 163, pp. F3197-P3208. [4] S. Cherevko, Electrochem. Commun., 2014, 48, pp. 81-85. [5] S. Cherevko, J. Electroanal. Chem., 2016(1), 773, pp 69-78. [6] S. Cherevko, J. Electroanal. Chem., 2016(2), 774, pp 102-110. [7] V. Pfeifer. Surf. Interface Anal., 2016, 48, pp. 261-273. [8] A. Minguzzi, Chem. Sci., 2014, 5, pp- 3591-3597. [9] A.H. Reksten, Phys. Chem. Chem. Phys., 2020, 22, pp. 18868-18881. [10] J.J. Veslasco-Vélez, J. Am. Chem. Soc., 2021, 143, pp. 12524-12534.

Dear reader, Please find attached the input files (.xml) and their corresponding outputs for the Exciting calculations of the imaginary component of the dielectric tensor ("XAS".dat) for: InP, GaP, red P and InPO4 which have been used in our publication:"Core-Hole Spectroscopy of Energy Conversion and Storage Related-Phosphorus Compounds Using Soft and Hard X rays".

The interaction of high-quality transition metal trichalcogenides (TMTs) single crystals FePX 3 (X: S, Se) with water molecules is studied using near-edge x-ray absorption fine structure (NEXAFS) and x-ray photoelectron spectroscopy (XPS) in a wide range of temperature and partial pressure of H 2 O. The physisorption nature of interaction between H 2 O and FePX 3 is found at low temperatures and relatively small concentrations of water molecules, that is supported by the DFT results. When temperature of the FePX 3 samples and partial pressure of H 2 O are increased, the interaction at the interface is defined by two competing processes—adsorption of molecules at high partial pressure of H 2 O and desorption of molecules due to the increased surface mobility and physisorption nature of interaction. Our intensive XPS/NEXAFS experiments accompanied by DFT calculations bring new understanding on the interaction of H 2 O with surface of a new class of 2D materials, TMTs, pointing to their stability and reactivity, that is important for further applications in different areas, like sensing and catalysis.

Since many decades nickel yttria-stabilized zirconia cermet (Ni/YSZ) has been the most frequently used fuel electrode material for high temperature solid oxide cells (SOCs). However, in recent years there has been considerable effort to improve the Ni/YSZ performance through surface engineering. In this work, we report a simple strategy to apply nanosized un-doped (CeOx) and Ni-doped (NiCeOy) ceria particles into porous Ni/YSZ cermet electrodes via infiltration from hexane solution. Detailed characterization of the particles in their solution revealed differences in the ease of agglomeration, with NiCeOy nanoparticles being better dispersed and thus forming smaller aggregates. This property is critical for the effectiveness of the solution in filling the pores of Ni/YSZ cermet and the consequent ceria deposition. In particular, morphological and microstructural characterization reveals that NiCeOy nanoparticles decorate uniformly the pores of Ni/YSZ backbone, deep up to the interface with the electrolyte. More importantly, this can be done with relatively high ceria loading per infiltration/co-firing step. Electrochemical tests demonstrate that infiltrated Ni/YSZ fuel electrodes have improved I-V performance in CO2 electrolysis as compared to pristine Ni/YSZ. Synchrotron-based operando NAP-XPS experiments using both soft and tender X-rays revealed the formation of an ultrathin Ni-Ce3+ layer on the electrode surface, which can rationalize the ameliorated CO2 electrolysis performance.

High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) employing a phosphoric acid H3PO4-doped membrane are considered to be promising sustainable electrochemical energy storage. The high-temperature operation has several advantages, such as a higher tolerance to CO poisoning, allowing coupling of HT-PEMFCs with reformers [1-3], as well the possibility for heat and electric energy co-generation [1,2]. However, during operation, phosphorus oxo-acids (e.g.: H3PO3) are generated on the anode. These impurities adsorb on the Pt catalyst [4-6], thus possibly negatively affecting the HT-PEMFCs performance. A detailed understanding of the H3PO3-catalyst (Pt) interaction is hence necessary for further HT-PEMFC optimization. However, besides an investigation of the H3PO3 adsorption behavior on Pt [6,7], literature on the behavior of the H3PO3 in contact with Pt (with/without polarization) is scarce. In this work, the oxidation mechanism of H3PO3 was investigated using a combination of in situ x-ray spectroscopy techniques that directly probe the H3PO3/Pt interface interaction, complemented by ex situ x-ray photoelectron spectroscopy (XPS) and ion-exchange chromatography (IEC). IEC gave insights into the effect of Pt on the stability of deaerated aqueous H3PO3 solutions. XPS was conducted on H3PO3/support structures (including Au and Pt supports) to determine to what extent the support affects the H3PO3 oxidation. Furthermore, in-situ dip and pull near-ambient pressure (NAP-)XPS was conducted to investigate the state of H3PO3 at the H3PO3/Pt interface and in solution bulk. It was observed that at the H3PO3/Pt interface, H3PO3 was chemically oxidized to H3PO4, while in the bulk solution it remains stable, as shown in Figure 1. Moreover, in situ x-ray absorption spectroscopy at the P K-edge was conducted at different concentrations of H3PO3 in aqueous solutions (i.e., different amounts of H2O) in contact with Pt, to determine the role of H2O in the oxidation of H3PO3. A higher degree of oxidation was observed for the less concentrated H3PO3, implying that H2O participates in the oxidation mechanism of H3PO3 to H3PO4. References: [1] Chandan et al., A.. J. Power Sources 2013, 231, 264–278. [2] Asensio, et al. Chem. Soc. Rev. 2010, 39 (8), 3210. [3] Q. Li et al, J. Electrochem. Soc. 2003, 150 (12), A1599. [4] Sugishima et al, J. Electrochem. Soc. 1994, 141 (12), 3332. [5] Doh et al. ChemElectroChem. 2014, 1 (1), 180–186. [6] Prokop et al, Electrochimica Acta 2015, 160, 214–218. [7] Prokop et al, Electrochimica Acta 2016, 212, 465–472. Figure 1