1. Carbon-supported iron complexes as electrocatalysts for the cogeneration of hydroxylamine and electricity in a NO-H2 fuel cell: A combined electrochemical and density functional theory study
- Author
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Annick Hubin, Xia Sheng, Ivo F.J. Vankelecom, Kristine Pierloot, Yolanda Alvarez-Gallego, Tzvetan Mihaylov, Xochitl Dominguez-Benetton, Hailiang Zhao, Kitty Baert, Paolo P. Pescarmona, Vrije Universiteit Brussel, Electrochemical and Surface Engineering, Materials and Chemistry, Earth System Sciences, and Product Technology
- Subjects
OXYGEN REDUCTION ,Materials science ,Activated carbon ,Inorganic chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,GAS-DIFFUSION ELECTRODES ,Hydroxylamine ,02 engineering and technology ,OXIDATION ,010402 general chemistry ,Electrochemistry ,Electrocatalyst ,01 natural sciences ,NITRIC-OXIDE REDUCTION ,NITROGEN-COMPOUNDS ,chemistry.chemical_compound ,METAL-ELECTRODES ,medicine ,SCHIFF-BASE COMPLEXES ,EXCHANGE-ENERGY ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,FeSalen ,Cogeneration of chemical products and electricity ,Gas diffusion electrode ,Renewable Energy, Sustainability and the Environment ,POROUS PLATINUM ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,NO-H-2 fuel cell ,chemistry ,Linear sweep voltammetry ,Phthalocyanine ,Electrocatalysis ,0210 nano-technology ,Carbon ,NO-H fuel cell ,medicine.drug - Abstract
Carbon-supported iron complexes were investigated as electrocatalysts for the reduction of nitric oxide (NO) in a H-2-NO fuel cell conceived for the production of hydroxylamine (NH2OH) with concomitant generation of electricity. Two types of iron complexes with tetradentate ligands, namely bis(salicylidene)ethylenediimine (Salen) and phthalocyanine (Pc), supported on activated carbon or graphite were prepared and evaluated as electrocatalysts, either without further treatment or after pyrolysis at 700 degrees C. The performance in the reduction of NO of gas diffusion cathodes based on these electrocatalysts was investigated in an electrochemical half cell (3-electrode configuration) using linear sweep voltammetry (LSV). The most promising electrocatalysts were studied further by chronoamperometric experiments in a H-2-NO fuel cell, which allowed comparison in terms of power output and hydroxylamine production. Depending on the concentration of the NO feed (6 or 18%), the best electrocatalytic performance was delivered either by FePc or FeSalen. The gas diffusion electrode based on FeSalen supported on activated carbon with 0.3 wt% Fe-loading provided the highest current density (86 A/m(2)) and the best current efficiency (43%) towards the desired NH2OH when operating at the higher NO concentration (18%). Moreover, FeSalen offers the advantage of being cheaper than FePc. The experimental work was complemented by density functional theory (DFT) calculations, which allowed to shed more light on the reaction mechanism for the reduction of nitric oxide at the atomistic level.
- Published
- 2018
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