Both high-entropy materials and metal–organic
frameworks
(MOFs) can be used as efficient catalysts for oxygen evolution, but
it remains a challenge to combine their advantages to further improve
the oxygen evolution reaction (OER). Herein, MOFs are served as precursors
to prepare the high-entropy metal sulfide (HEMS) (MnFeCoNiCu)S2 nanoparticles based on the maximized configurational entropy
theory, exhibiting ultra-efficient OER performance. The strong synergistic
effect among Mn, Fe, Co, Ni, and Cu builds a stable electronic structure
and provides a favorable local coordination environment, which enhance
the catalytic performance greatly. In addition, the appropriate doping
of sulfur source contributes to modulate the electronic structure,
which promotes the formation of single-phase HEMS nanoparticles with
the dimeter of sub-3 nm. The (MnFeCoNiCu)S2 nanoparticles
display the best OER performance (a low overpotential of 221 mV at
10 mA cm–2 in 1 M KOH solution) and good stability
(remains to be 97.6% after 12 h by chronoamperometry). This work provides
a potential application for high-entropy materials based on MOF precursors
as OER catalysts.
Realizing a high-efficiency electrochemical oxygen evolution reaction (OER) is a great challenge in water splitting and metal−air battery fields due to the slow reaction kinetics. Herein, a synchronous dual-phase synthetic strategy is developed to successfully construct a cactus-like dual-phase bimetallic metal− organic framework (MOF) on a nickel foam (NF) substrate (noted as NiFe-MOF@NF). It is constituted by Ni-main NiFe-MOF and Fe-main NiFe-MOF. When functioning as an anode, the freestanding cactus-like dual-phase NiFe-MOF@NF catalyst merely requires a lower overpotential of 277 mV to supply 100 mA cm −2 with robust stability (90% retainment of initial current density after 24 h chronoamperometry measurement). Density functional theory calculations on the NiFe-MOF@NF catalyst reveal that the combination of Ni and Fe has efficiently modulated the electron configuration of metal centers and optimized the absorption/desorption of OER oxygen-containing intermediates. Thus, we demonstrate a novel synchronous dual-phase synthetic strategy to engineer freestanding dual-phase electrocatalysts, which feature multiple synergetic effects considerably boosting OER performance for optimizing the energy conversion and storage system.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.