Bimetallic-ZIFs derived quaternary amorphous LDHs decorated with crystalline Ag nanoparticles for highly efficient oxygen evolution reaction

Amorphous LDHs materials have been considered promising electrocatalysts for OER since their abundant coordination sites but still undergo poor stability. It is an efficient strategy to rationally architect amorphous/crystalline hybrid nanostructures on the ZIFs-derived amorphous LDH counterparts. Herein, we provide a facile two-step method to fabricate crystalline Ag NPs decorated amorphous QLDHs (Ag/QLDHs) nanosheet arrays on the Ni foam through ions exchange and spontaneous redox reaction. Based on the multi-metal synergetic effects (Co, Zn, Fe, Ni) and regulation of Ag nanoparticles (NPs), the as-formed Ag/QLDHs with heterogeneously hierarchal structures exhibit excellent OER performance with a low overpotential of 216 and 247 mV under 10 and 100 mA cm−2 in 1 M KOH, respectively, together with highly structural robustness. Through using the in situ-Raman spectroscopy, we reveal that the Ag NPs play the important role in enhancing the oxidation state of Ni and Fe species in Ag/QLDHs, which facilitates the generation of active MOx(OH)y at a much lower potential. The synthesized approach proposed in this work will supply a promising pathway for constructing amorphous/crystalline hybrid structures applied to alkaline water oxidation.