Phytic Acid‐Based FeCo Bimetallic Metal‐Organic Gels for Electrocatalytic Oxygen Evolution Reaction

Abstract

Electrocatalysts have been developed to improve the efficiency of gas release for oxygen evolution reaction (OER), and finding a simple and efficient method for efficient electrocatalysts has inspired research enthusiasm. Herein, we report bimetallic metal‐organic gels derived from phytic acid (PA) and mixed transition metal ions to explore their performance in electrocatalytic oxygen evolution reaction. PA is a natural phosphorus‐rich organic compound, which can be obtained from plant seeds and grains. PA reacts with bimetallic ions (Fe3+ and Co2+) in a facile one‐pot synthesis under mild conditions to form PA‐FeCo bimetallic gels, and the corresponding aerogels are further partially reduced with NaBH4 to improve the electrocatalytic activity. Mixed valence states of Fe(II)/Fe(III) and Co(III)/Co(II) are present in the materials. Excellent OER performance in terms of overpotential (257 mV at 20 mA cm−2) and Tafel slope (36 mV dec−1) is achieved in an alkaline electrolyte. This reduction method is superior to the pyrolysis method by well maintaining the gel morphology structure. This strategy is conducive to the further improvement of the performance of metal‐organic electrocatalysts, and provides guidance for the subsequent application of metal‐organic gel electrocatalysts.

B, N-co-doped and C-coated Co2P composite derived from phytate derivatives as a high-efficiency HER electrocatalyst

“…The peaks located at 29.54° and 30.05° correspond to the (012) and (302) crystal plane of Co 2 P 2 O 7 , and the peaks at 21.82°, 23.02° and 25.88° correspond to the (101), (111) and (210) crystal plane of Co 3 (PO 4 ) 2 , indicating that pyrophosphate (Co 2 P 2 O 7 ) and phosphate (Co 3 (PO 4 ) 2 ) may have been produced after the HER test. 60 Fig. 7(b) and (c) show the TEM and HRTEM images of the Co 2 P@BNC catalyst after the HER test.…”

“…7 CrystEngComm Paper produced after the HER test. 60 Fig. 7(b) and (c) show the TEM and HRTEM images of the Co 2 P@BNC catalyst after the HER test.…”

Metal–organic gels and their derived materials for electrochemical applications

“…Feng et al reported bimetallic PA-FeCo MOGs of PA and mixed Fe 3+ /Co 2+ metal ions to investigate their electrocatalytic OER activity. 147 The bimetallic PA-FeCo-1:2:2 aerogel has a crosslinked network structure composed of irregular nanoparticles of ca. 35 nm in diameter.…”

Metal‐Organic Gels of Tris‐tetrazole‐tri‐amido Molecule with Co(II) and Ni(II) as Effective Electrocatalysts for Oxygen Evolution Reaction: Effect of Metal Ion, Porosity and Morphology on the Catalytic Activity of MOGs

“…The organic ligands, containing carboxylates, cyanides, imidazoles, tetrazoles or porphyrins, linked by inorganic metal ions or cluster of metal ions facilitate electrocatalytic activity for water splitting by enhancing electron transfer rate. In this regard, transition metal‐based MOFs and gels are anticipated to provide the desired solution for non‐precious electrocatalysts for water splitting [20–25] . In the past few years, extensive studies have been done on the water splitting reaction utilizing various MOFs and MOF derived materials having diverse structural features, morphologies and catalytic activities [26–30] .…”