From Nickel Foam to Highly Active NiFe‐based Oxygen Evolution Catalysts

Abstract

A key challenge for the large‐scale application of the oxygen evolution reaction (OER) is the synthesis of active, cheap and robust catalysts. Here, a straightforward procedure to form novel porous and highly active multimetallic oxygen evolution catalysts was reported. They were derived from an original dendritic nickel foam (NiNF) using two strategies: i) Fe‐doping; and ii) Fe/Cr‐doping. A bimetallic NiFe catalyst, formed through controlled acid treatment followed by a simple galvanic exchange procedure proved remarkably active in 1 m KOH with a very low overpotential value of η200=276 mV at 200 mA cm−2 and a very low Tafel slope of 25 mV dec−1. A trimetallic FeNiCr catalyst, containing 11 % Cr, was also synthesised through electrodeposition and partial Cr leaching, to form a stable OER catalyst displaying a very low overpotential value of η200=279 mV at 200 mA cm−2 and a Tafel slope of 29 mV dec−1. These two novel catalysts are among the best performing OER catalysts reported so far.

Ultrafast Room‐Temperature Synthesis of Large‐Scale, Low‐Cost, and Highly Active Ni─Fe Based Electrodes toward Industrialized Seawater Oxidation

“…As shown in Figure 5b the overpotential of 60Fe/NF at 10 mA cm −2 is compared with those of other Ni and Fe‐based catalysts such as Fe‐18 h/NF, [ 4 ] γ‐FeOOH/NF, [ 15 ] NiFe BTC‐GNPs, [ 42 ] NiFe‐LDH, [ 43 ] FeOOH/Ni(OH) 2 /NF, [ 44 ] β‐NiFeOOH/NF, [ 10 ] NiFeMo, [ 45 ] FeNiCr−NiNFc [ 46 ] , and NiFe‐LDH/MXene/NF. [ 47 ] It is found that 60Fe/NF with relatively low overpotential is competitive compared to other Ni─Fe based catalysts.…”

Robust and Bifunctional Electrodeposited NiCoCr Ternary Alloy for Alkaline Water Electrolysis

“…In contrast, the values of 0.4/0.4/0.2 determined for NiCoCr were consistent with the loss of some Cr(VI) in the form of CrO 4 2− chromate species dissolved in the electrolyte solution, as previously reported by Peugeot et al for NiFeCr electrodes. [ 48 ]…”