Facile Synthesis of Two‐Dimensional Iron/Cobalt Metal–Organic Framework for Efficient Oxygen Evolution Electrocatalysis

Abstract

A facile synthesis is reported of two‐dimensional (2D) bimetallic (Fe/Co=1:2) metal–organic frameworks (MOF, ca. 2.2 nm thick) via simple stirring of the reaction mixture of Fe/Co salts and 1,4‐benzene dicarboxylic acid (1,4‐BDC) in the presence of triethylamine and water at room temperature. The mechanism of the 2D, rather than bulk, MOF was revealed by studying the role of each component in the reaction mixture. It was found that these 2D MOF‐Fe/Co(1:2) exhibited excellent electrocatalytic activity for the oxygen evolution reaction (OER) under basic conditions. The electrocatalytic mechanism was disclosed via both experimental results and density functional theory (DFT) calculation. The 2D morphology and co‐doping of Fe/Co contributed to the superior OER performance of the 2D MOF‐Fe/Co(1:2). The simple and efficient synthetic method is suitable for the mass production and future commercialization of functional 2D MOF with low cost and high yield.

Recent Progress on Two-Dimensional Materials

“…However, the poor mass permeability, low conductivity and blockage of active sites by organic ligands have limited their applications. On the other hand, the electron transfer and mass transport properties can be greatly improved by adopting 2D MOF structures 1058 . Ge et al designed a simple way to prepare 2D MOF-Fe/Co nanosheets by stirring the mixture of Fe/Co salts and 1,4-BDC 1058 .…”

“…On the other hand, the electron transfer and mass transport properties can be greatly improved by adopting 2D MOF structures 1058 . Ge et al designed a simple way to prepare 2D MOF-Fe/Co nanosheets by stirring the mixture of Fe/Co salts and 1,4-BDC 1058 . Water and TEA are important additives to stabilize the MOF nanosheets.…”

Understanding the Effect of Second Metal on CoM (M = Ni, Cu, Zn) Metal–Organic Frameworks for Electrocatalytic Oxygen Evolution Reaction

“…[24,25] More importantly, the structural flexibility of most Co-based MOFs allows the design and fabrication of bimetallic MOFs with different second metal, leading to higher catalytic performance. [26][27][28][29][30][31][32] For example, Li et al reported that the CoZn bimetallic MOFs could exhibit OER activity with the overpotential of 320 mV at a current density of 10 mA cm −2 due to dimensionality and pore-geometry. [33] Furthermore, Bu et al reported that the CoNi bimetallic 2D-MOFs exhibited excellent OER activity with the overpotential of 240 mV at 10 mA cm −2 , thanks to the CoNi coupling effect and the unsaturated active sites.…”

Realizing electrochemical transformation of a metal–organic framework precatalyst into a metal hydroxide–oxy(hydroxide) active catalyst during alkaline water oxidation

“…36,73,78,86 It is observed that the ultrathin nanosheets prepared by electrochemical transformation have several advantages. [129][130][131][132] As a result, the electrochemically synthesized ultrathin M(OH) 2 -M(O) x (OH) y nanosheets show an excellent catalytic performance for water oxidation. 36,73,78,86 The major advantages of the electrochemically synthesized ultrathin M(OH) 2 -M(O) x (OH) y nanosheets are described as follows (Fig.…”