• Energy Research

AbstractThe electrochemical stability of thermally prepared Ir oxide films is investigated using a scanning flow cell (SFC)–inductively coupled plasma mass-spectrometer (ICP-MS) setup under transient and stationary potential and/or current conditions. Time-resolved dissolution rates provide important insights into critical conditions for material breakdown and a fully quantitative in-situ assessment of the electrochemical stability during oxygen evolution reaction (OER) conditions. In particular, the results demonstrate that stability and OER activity of the IrOx catalysts strongly depend on the chemical and structural nature of Ir oxide species and their synthesis conditions.

Demand response is a viable concept to deal with and benefit from fluctuating electricity prices and is of growing interest to the electrochemical industry. To assess the flexibility potential of such processes, a generic, interdisciplinary methodology is required. We propose such a methodology, in which the electrochemical fundamentals and the theoretical potential are determined first by analyzing strengths, weaknesses, opportunities, and threats. Afterward, experiments are conducted to determine selectivity and yield under varying loads and to assess the additional long-term costs associated with flexible operation. An industrial-scale electrochemical process is assessed regarding its technical, economic, and practical potential. The required steps include a flow sheet analysis, the formulation and solution of a simplified model for operation scheduling under various business options, and a dynamic optimization based on rigorous, dynamic process models. We apply the methodology to three electrochemical processes of different technology readiness levels—the syntheses of hydrogen peroxide, adiponitrile, and 1,2-dichloroethane via chloralkali electrolysis—to illustrate the individual steps of the proposed methodology.

Increasing the performance of seawater electrolyser and enabling direct natural seawater feed by asymmetric electrolyte flow scheme.

Catholyte flow compartment design impacts the CO2RR product selectivity by influencing gas bubble transport and local pH. According to the hydrodynamic volcano model, an optimal catholyte fluid velocity enables the highest CO2 reduction selectivity.

Review Article Published: 17 February 2020 Electrolysis of low-grade and saline surface water Wenming Tong, Mark Forster, Fabio Dionigi, Sören Dresp, Roghayeh Sadeghi Erami, Peter Strasser, Alexander J. Cowan & Pau Farràs Nature Energy (2020)Cite this article 1779 Accesses 1 Citations 60 Altmetric Metricsdetails Abstract Powered by renewable energy sources such as solar, marine, geothermal and wind, generation of storable hydrogen fuel through water electrolysis provides a promising path towards energy sustainability. However, state-of-the-art electrolysis requires support from associated processes such as desalination of water sources, further purification of desalinated water, and transportation of water, which often contribute financial and energy costs. One strategy to avoid these operations is to develop electrolysers that are capable of operating with impure water feeds directly. Here we review recent developments in electrode materials/catalysts for water electrolysis using low-grade and saline water, a significantly more abundant resource worldwide compared to potable water. We address the associated challenges in design of electrolysers, and discuss future potential approaches that may yield highly active and selective materials for water electrolysis in the presence of common impurities such as metal ions, chloride and bio-organisms.

AbstractThe electrochemical conversion of 5-Hydroxymethylfurfural, especially its reduction, is an attractive green production pathway for carbonaceous e-chemicals. We demonstrate the reduction of 5-Hydroxymethylfurfural to 5-Methylfurfurylalcohol under strongly alkaline reaction environments over oxide-derived Cu bimetallic electrocatalysts. We investigate whether and how the surface catalysis of the MOx phases tune the catalytic selectivity of oxide-derived Cu with respect to the 2-electron hydrogenation to 2.5-Bishydroxymethylfuran and the (2 + 2)-electron hydrogenation/hydrogenolysis to 5-Methylfurfurylalcohol. We provide evidence for a kinetic competition between the evolution of H2 and the 2-electron hydrogenolysis of 2.5-Bishydroxymethylfuran to 5-Methylfurfurylalcohol and discuss its mechanistic implications. Finally, we demonstrate that the ability to conduct 5-Hydroxymethylfurfural reduction to 5-Methylfurfurylalcohol in alkaline conditions over oxide-derived Cu/MOx Cu foam electrodes enable an efficiently operating alkaline exchange membranes electrolyzer, in which the cathodic 5-Hydroxymethylfurfural valorization is coupled to either alkaline oxygen evolution anode or to oxidative 5-Hydroxymethylfurfural valorization.

Establishing new reactivity map descriptor of TOF–SD for PGM-free Fe–N–C catalysts ORR activity.