Morphologically Controlled Metal–Organic Framework-Derived FeNi Oxides for Efficient Water Oxidation

Abstract

The complex oxygen evolution reaction (OER) is recognized as the most studied and explored electrochemical conversion, which plays a crucial role in energy-related applications. In this work, a series of metal−organic framework (MOF)derived FeNi oxides from a barrel-shaped Ni-based BMM-10 precursor are conveniently obtained to show an excellent OER performance. Under mild Fe(III) etching, a type of core−shell Fe 0.5 -BMM-10 can be well preserved and the coordination bond of the middle frame structure is decomposed. Furthermore, the Fe x -BMM-10-T series is successfully synthesized with a well-preserved morphology compared to precursors after direct oxidation. Finally, followed by initial electrochemical activation, the decomposition of FeNi oxides generates active Fe-doped nickel oxyhydroxides for efficient water oxidation. The improved OER performance stems from the high specific surface area and abundant exposed active centers, as well as the significant synergistic effect between iron and nickel, which is further verified by the theoretical calculation. This approach can be extended to precisely adjust the morphology of MOFs and their derivatives that can result in superior electrocatalytic properties in terms of energy conversion and storage applications.

Different Growth Behavior of MOF‐on‐MOF Heterostructures to Enhance Oxygen Evolution

“…Furthermore, FeNi‐NC‐800 owns the smallest Tafel slope of 82 mV dec −1 to verify its favorable reaction kinetics (Figures 6b, S17). The electrochemically active surface area (ECSA) can be further reflected by the calculated double‐layer capacitance ( C dl ), and all carbon materials exhibit excellent linearity in Figure S18 [32] . As shown in Figure 6c, the C dl value of FeNi‐NC‐800 is fitted to be 18.8 mF cm −2 , significantly larger than those of FeNi‐NC‐900 (10.8 mF cm −2 ), FeNi‐NC‐1000 (7.9 mF cm −2 ), Ni‐NC (1.4 mF cm −2 ), and RuO 2 (4.2 mF cm −2 ).…”

Beyond Pristine Metal–Organic Frameworks: Preparation of Hollow MOFs and Their Composites for Catalysis, Sensing, and Adsorption Removal Applications

“…Due to its rigid structure and the synergistic effect between the cavity and the bimetal, the charge-transfer resistance of the composite is only 42 Ω, and the phase-education of the solid Co-MOF has better electrocatalytic performance. In addition, hollow-MOF-derived materials have also been used in the field of electrochemical conversion [81][82][83][84]. By adjusting the morphologies of MOFs, the resultant materials can produce superior electrocatalytic properties in terms of energy conversion and storage applications.…”

Ultrafine IrRu Nanoparticles toward Efficient Oxygen Evolution Reaction in Acidic Media

“…Water electrolysis has been regarded as one of the most promising strategies for widespread hydrogen production. PEMWEs and alkaline water electrolyzers (AWEs) represent two major hydrogen production technologies. − PEMWEs can produce much purer hydrogen at a larger current density and a higher energy efficiency as compared to AWEs. However, a grand challenge of PEMWEs is the slow kinetics of acidic OER, which involves multiple electron transfer and a high reaction energy barrier .…”