Metal‐Rich Chalcogenides as Sustainable Electrocatalysts for Oxygen Evolution and Reduction: State of the Art and Future Perspectives

Abstract

The rational design of high-performance and costeffective electrocatalysts is a key for the development of sustainable energy systems such as electrolyzers, fuel cells and metal-air batteries. Although water splitting and fuel cells are commercially mature technologies, they are still limited on large scale primarily due to the abundancy of the currently utilized expensive materials as well as the sluggish kinetics of the underlaying reactions, oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), and thus the required large observed overpotentials. Therefore, an efficient inexpensive catalyst is necessary. In the last decade, metal chalcogenides have

Tailoring the Electrocatalytic Activity of Pentlandite FexNi9‐XS8 Nanoparticles via Variation of the Fe : Ni Ratio for Enhanced Water Oxidation

“…A recent summary of the catalytic activity parameters for metal-rich chalcogenides towards OER has been presented in our previous comprehensive review. [2] Herein, the η 10 values of relevant materials for OER from literature are provided for comparison. Impressively, our electrode outperformed NiFe-LDH catalyst (η 10 = 390 mV) and other metal chalcogenides and pentlandites such as NiS x (η 10 = 480 mV) and NiSe x (η 10 = 460 mV).…”

“…[1,2] Among others, water electrolysis, fuel cells and metal-air batteries are the most promising sustainable energy devices. [2,3] However, in alkaline water electrolysis, the underpinning reaction, the oxygen evolution reaction (OER), is a current challenge due to its sluggish kinetics and thus the required high overpotentials. Hence, it is imperative to search for high performance oxygen electrocatalysts.…”

“…[20,21] Most recently, we have published a comprehensive review on metal-rich chalcogenides including pentlandites (M 9 S 8 ) as electrocatalyst for oxygen evolution and reduction. [2] For example, the pentlandite Fe 4.5 Ni 4.5 S 8 was synthesized by high-temperature methods from the elements and showed enhanced activity towards HER and CO 2 reduction. [20,22,23] The synthesized pentlandite material possesses the advantages of high chemical stability under reductive potentials, mechanical robustness, high electronic conductivity through the Fe-and Ni-centres bridged by S and intrinsically metallic behaviour, which mainly originates from the continuous network of metal-metal bonds.…”

“…[20,22,23] The synthesized pentlandite material possesses the advantages of high chemical stability under reductive potentials, mechanical robustness, high electronic conductivity through the Fe-and Ni-centres bridged by S and intrinsically metallic behaviour, which mainly originates from the continuous network of metal-metal bonds. [2,20] Similar to FeNi LDH catalyst, the pentlandite contains Fe and Ni active species, making it promising catalyst for OER.…”

Electrochemistry: Retrospect and Prospects

“…[127] Also, structural motifs of enzymes have motivated use of several bimetallic chalcogenides including pentlandites as OER catalysts. [129] ORR proceeds by a multi-electron, multi-step process. [130] Non-metal catalysts for ORR include Ag, MnO 2 , FeÀ Co oxides and macrocyclics.…”