Relationships between intrinsic and structural chirality in dimeric liquid crystals are explored using new lactate-based chiral compounds exhibiting the rarely-observed chiral N*TB phase. Comparisons of enantiomeric and racemic ...
Magnetic Field‐Enhanced Electrocatalytic Oxygen Evolution on a Mixed‐Valent Cobalt‐Modulated LaCoO3 Catalyst
Von Wiley-VCH zur Verfügung gestellt
A novel “mixed-valent cobalt modulation” strategy is presented to enhance the electrocatalytic oxygen evolution reaction (OER) performance of perovskite LaCoO3 (LCO). An optimized catalyst with 1.98 % Co2+/Co3+ exhibits a significant magnetic-field enhancement for the OER activity.
Extensive efforts to enhance the oxygen evolution reaction (OER) catalytic performance of transition metal oxides mainly concentrate on the extrinsic morphology tailoring, lattice doping, and electrode interface optimizing. Nevertheless, little room is left for performance improvement using these methods and an obvious gap still exists compared to the precious metal catalysts. In this work, a novel “mixed-valent cobalt modulation” strategy is presented to enhance the electrocatalytic OER of perovskite LaCoO3 (LCO) oxide. The valence transition of cobalt is realized by ethylenediamine post reduction procedure at room temperature, which further induces the variation of magnetic properties for LCO catalyst. The optimized LCO catalyst with Co2+/Co3+ of 1.98 % exhibits the best OER activity, and the overpotential at 10 mA cm−2 current density is decreased by 170 mV compared pristine LCO. Impressively, the ferromagnetic LCO catalyst can perform magnetic OER enhancement. By application of an external magnetic field, the overpotential of LCO at 10 mA cm−2 can be further decreased by 20 mV compared to that of under zero magnetic field, which arises from the enhanced energy states of electrons and accelerated electron transfer process driven by magnetic field. Our findings may provide a promising strategy to break the bottleneck for further enhancement of OER performance.Zum Volltext
Jetzt nächsten Artikel lesen:
Überprüfung Ihres Anmeldestatus ...
Wenn Sie ein registrierter Benutzer sind, zeigen wir in Kürze den vollständigen Artikel.