Details

Autor(en) / Beteiligte

• Senthil Raja, Duraisamy
• Ting, Yu-Chieh
• Lin, Ting-Yu
• Cheng, Chih-Chieh
• Chen, Po-Wei
• Yen, Fan-Yu
• Lu, Shih-Yuan

Titel

Quad-metallic MOF-derived carbon-armored pseudo-high entropy alloys as a bifunctional electrocatalyst for alkaline water electrolysis at high current densities

Ist Teil von

• Journal of materials chemistry. A, Materials for energy and sustainability, 2023-11, Vol.11 (46), p.25283-25297

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A new catalyst design, pseudo-high entropy alloy (HEA), was proposed and demonstrated for high performance water electrolysis. Pseudo-HEAs, defined as single-phase four-element alloys of molar configurational entropy greater than 1.36 R , are in general easier to design and prepare for enhanced electrocatalytic efficiency as compared with traditional HEAs of five or more elements. A carbon armored pseudo-HEA catalyst, FeCoNiMo@C, was synthesized with a simple two-stage thermal conversion of FeCoNiMo-MOF, grown in situ on a nickel foam (NF) substrate, to exhibit outstanding catalytic efficiency and stability toward water electrolysis in alkaline media. It delivered 10 and 500 mA cm −2 at ultra-low overpotentials of 55 and 233 mV, respectively for the hydrogen evolution reaction and 204 and 273 mV, respectively for the oxygen evolution reaction. The FeCoNiMo@C/NF//FeCoNiMo@C/NF couple achieved ultra-low cell voltages of 1.488 V@10 mA cm −2 and 1.725 V@500 mA cm −2 for full cell water splitting and ultra-stability at an industrially applicable high current density of 500 mA cm −2 with a minor decay of 3.4% over 50 h. The success was attributed to the atomic scale synergy between constituent atoms, Fe, Co, Ni and Mo, atomically dispersed in the pseudo-HEA. A quad-metallic pseudo-HEA catalyst, FeCoNiMo@C, was developed for water electrolysis, exhibiting outstanding bifunctional catalytic efficiency and stability, 500 mA cm −2 @1.725 V and a 3.4% decay after a 50 h operation at 500 mA cm −2 .