Details

Autor(en) / Beteiligte

• Lv, Haoyuan
• Zhang, Xue-Peng
• Guo, Kai
• Han, Jinxiu
• Guo, Hongbo
• Lei, Haitao
• Li, Xialiang
• Zhang, Wei
• Apfel, Ulf-Peter
• Cao, Rui

Titel

Coordination Tuning of Metal Porphyrins for Improved Oxygen Evolution Reaction

Ist Teil von

• Angewandte Chemie International Edition, 2023-09, Vol.62 (38), p.e202305938-e202305938

Auflage

International ed. in English

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The nucleophilic attack of water or hydroxide on metal-oxo units forms an O-O bond in the oxygen evolution reaction (OER). Coordination tuning to improve this attack is intriguing but has been rarely realized. We herein report on improved OER catalysis by metal porphyrin 1-M (M = Co, Fe) with a coordinatively unsaturated metal ion. We designed and synthesized 1-M by sterically blocking one porphyrin side with a tethered tetraazacyclododecane unit. With this protection, the metal-oxo species generated in OER can maintain an unoccupied trans axial site. Importantly, 1-M displays a higher OER activity in alkaline solutions than analogues lacking such an axial protection by decreasing up to 150-mV overpotential to achieve 10 mA/cm2 current density. Theoretical studies suggest that with an unoccupied trans axial site, the metal-oxo unit becomes more positively charged and thus is more favoured for the hydroxide nucleophilic attack as compared to metal-oxo units bearing trans axial ligands.