Efficient and Highly Stable 3D-Printed NiFe and NiCo Bifunctional Electrodes for Practical HER and OER
Résumé
Considered like a fully renewable and clean energy carrier with the highest density, dihydrogen (H2) constitutes best alternative to fossil fuels for ensuring sustainability of energy. This technologically industrially relevant vector can be produced by water electrolysis that is now widely recognized as an eco-friendly, scalable, carbon-free route. In context, alkaline affordable technology because it allows use transition metals electrocatalysts both hydrogen (HER) oxygen (OER) evolution reactions. Here, combining catalytically active metal alloys (NiFe NiCo) 3D printing technique, namely, selective laser melting (SLM), enables access ca. 25 cm2 microstructured cylindrical electrodes, efficiently promoting HER OER. NiCo found most efficient electrode HER, overpotential 210 mV at 10 mA cm–2. It also stable when studied in operation during prolonged electrolysis, potential change only 40 after 140 h 50 cm–2 (1.25 A). Regarding OER, NiFe shows catalytic activity 300 greatest stability electrolysis-induced 30 mV. Further surface characterization techniques (scanning electron microscopy (SEM), dispersive X-ray spectroscopy (EDS), contact angle measurements, analysis electrogenerated gas bubbles) are used monitor chemical changes get valuable information on bubble dynamics. Interestingly, beneficial enhancing hydrophilicity and/or aerophobicity thus facilitating detachment H2 or O2 bubbles.
Mots clés
Overpotential
Electrolysis
Electrolysis of water
Alkaline water electrolysis
Water splitting
Oxygen evolution
Materials science
Chemical engineering
Electrode
Bifunctional
Electrocatalyst
Nanotechnology
Chemistry
Catalysis
Electrochemistry
Photocatalysis
Organic chemistry
Physical chemistry
Engineering
Electrolyte