Novel alkaline water electrolysis with nickel-iron gas diffusion electrode for oxygen evolution

Koj, Matthias; Qian, Jingcan; Turek, Thomas

doi:10.1016/j.ijhydene.2019.09.122

Cited by 35 publications

(38 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The activation overvoltages are defined by the electrode materials. Whereas nickel is the most-used electrode material, it provides very high overvoltages for the oxygen and hydrogen evolution reactions [41][42][43][44]. Hence, electrocatalytic materials are added to the electrodes.…”

Section: Cell Design and Cell Voltagementioning

confidence: 99%

See 1 more Smart Citation

Alkaline Water Electrolysis Powered by Renewable Energy: A Review

2020

Self Cite

View full text Add to dashboard Cite

Alkaline water electrolysis is a key technology for large-scale hydrogen production powered by renewable energy. As conventional electrolyzers are designed for operation at fixed process conditions, the implementation of fluctuating and highly intermittent renewable energy is challenging. This contribution shows the recent state of system descriptions for alkaline water electrolysis and renewable energies, such as solar and wind power. Each component of a hydrogen energy system needs to be optimized to increase the operation time and system efficiency. Only in this way can hydrogen produced by electrolysis processes be competitive with the conventional path based on fossil energy sources. Conventional alkaline water electrolyzers show a limited part-load range due to an increased gas impurity at low power availability. As explosive mixtures of hydrogen and oxygen must be prevented, a safety shutdown is performed when reaching specific gas contamination. Furthermore, the cell voltage should be optimized to maintain a high efficiency. While photovoltaic panels can be directly coupled to alkaline water electrolyzers, wind turbines require suitable converters with additional losses. By combining alkaline water electrolysis with hydrogen storage tanks and fuel cells, power grid stabilization can be performed. As a consequence, the conventional spinning reserve can be reduced, which additionally lowers the carbon dioxide emissions.

show abstract

Section: Cell Design and Cell Voltagementioning

confidence: 99%

“…Hence, electrocatalytic materials are added to the electrodes. Iron is a cost-efficient catalyst for the oxygen evolution reaction [41,42,45]. Molybdenum decreases the overvoltage for the evolution of hydrogen at the cathode [44,46,47].…”

Section: Cell Design and Cell Voltagementioning

confidence: 99%

Alkaline Water Electrolysis Powered by Renewable Energy: A Review

2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Therefore, we tried to prepare nickel and silver layers with comparable pore systems. Koj et al [21] . reported mean pore diameters of approximately 2 μm and a wide distribution of up to 10 μm for pure nickel GDEs.…”

Section: Resultsmentioning

confidence: 99%

“…[20] Therefore, we tried to prepare nickel and silver layers with comparable pore systems. Koj et al [21] reported mean pore diameters of approximately 2 μm and a wide distribution of up to 10 μm for pure nickel GDEs. For the oxygen reduction reaction (ORR) in silver-based electrodes, pore diameters of 0.7 μm are best suited.…”

Section: Analysis Of the Pore Systemmentioning

confidence: 99%

“…The electrodes are prepared batch wise by means of a wet spraying process inspired by the work of Moussallem et al [13] and described in detail in previous publications. [20,21] A metal containing suspension is sprayed on a nickel mesh (106 μm × 118 μm mesh size, 63 μm wire thickness, Haver & Boecker OHG) as support and conducting agent using an airbrush gun (Evolution, 0.6 mm pin hole, Harder & Steenbeck). A heating table allows to simultaneously dry each layer while being applied resulting in a homogeneous electrode surface.…”

Section: Electrode Preparationmentioning

confidence: 99%

See 1 more Smart Citation

Experimental and Model‐Based Analysis of Electrolyte Intrusion Depth in Silver‐Based Gas Diffusion Electrodes

2021

Self Cite

View full text Add to dashboard Cite

The electrolyte distribution is a central point of discussion for understanding the processes inside gas-diffusion electrodes (GDE) for the oxygen reduction reaction in highly alkaline media. During first radiographic operando synchrotron experiments, the liquid electrolyte was located, however, the through-plane distribution remains unclear. Therefore, model electrodes consisting of nickel and silver layers are developed to determine the electrolyte intrusion depth. Nickel-based GDEs are modified to achieve a pore system morphology suitable for the oxygen reduction reaction and subsequently coated with silver-PTFE catalyst layers. These graded electrodes form gasdiffusion (nickel) and reaction (silver) layers. The electrodes performance is determined under industrial conditions (80°C, 30 wt % NaOH electrolyte) as a function of the silver layer thickness and thus of the effective intrusion depth of the electrolyte. The model-based analysis confirms the experimental determined intrusion depths. Nevertheless, additional operando tomography measurements would help to further improve the understanding of the processes inside GDE.

show abstract

In Situ Reconstruction of Helical Iron Borophosphate Precatalyst toward Durable Industrial Alkaline Water Electrolysis and Selective Oxidation of Alcohols

Yang,

Vijaykumar,

Chen

et al. 2023

Adv Funct Materials

View full text Add to dashboard Cite

Iron‐based (pre)catalysts have attracted enormous attention for various electrooxidation reactions due to the low cost, high abundance, and multiple accessible redox states of iron. Herein, a well‐defined helical iron borophosphate (LiFeBPO) is developed as an electro(pre)catalyst for the oxygen evolution reaction (OER) and selective alcohol oxidation. When deposited on nickel foam (NF), LiFeBPO exhibits an exceptional OER performance at ambient conditions attaining a current density of 100 mA cm−2 at ≈276 mV overpotential in 1 m KOH. Notably, this anode sustains durable alkaline water electrolysis at 500 mA cm−2 for over 330 h under industrial conditions (6 m KOH and 85 °C). In –situ and ex situ investigations reveal a deep reconstruction of LiFeBPO during OER, which transforms into a 3D open porous skeleton assembled by ultrasmall, low‐crystalline α‐FeOOH nanoparticles (interfacing with NiOOH of NF). This structure contributes to exposing accessible surface active sites, as well as accelerating mass transport and bubble detachment. Moreover, this electrode also catalyzes the electrooxidation of alcohols (methanol, ethylene glycol, and glycerol) to formic acid (FA) with high selectivity and full conversion. This study provides promising solutions for designing suitable anodes for the simultaneous production of green hydrogen fuel and value–added FA from electrooxidation reactions.

show abstract

Novel alkaline water electrolysis with nickel-iron gas diffusion electrode for oxygen evolution

Cited by 35 publications

References 44 publications

Alkaline Water Electrolysis Powered by Renewable Energy: A Review

Alkaline Water Electrolysis Powered by Renewable Energy: A Review

Experimental and Model‐Based Analysis of Electrolyte Intrusion Depth in Silver‐Based Gas Diffusion Electrodes

In Situ Reconstruction of Helical Iron Borophosphate Precatalyst toward Durable Industrial Alkaline Water Electrolysis and Selective Oxidation of Alcohols

Contact Info

Product

Resources

About