Metal‐Rich Chalcogenides for Electrocatalytic Hydrogen Evolution: Activity of Electrodes and Bulk Materials

Abstract

rich chalcogenides composed of highly abundant elements recently emerged as promising catalysts for the electrocatalytic hydrogen evolution reaction (HER). Many of these materials benefit from a high intrinsic conductivity as compared to their chalcogen-rich congeners, greatly reducing the necessity for conductive additives or sophisticated nanostructuring. Herein, we showcase the high potential of metal-rich transitionmetal chalcogenides for the electrocatalytic hydrogen formation by summarizing the recent progress achieved with M 9 S 8 (pentlandite type) and M 3 S 2 (heazlewoodite type) based materials, which represent the most frequently applied compositions for this purpose. By a detailed electrochemical comparison of bulk as well as pellet electrodes of metal-rich Fe 4.5 Ni 4.5 S 8 , we also aim at raising awareness in the community for the inherent differences in catalytic properties of the materials themselves and those of the fabricated electrodes, a point that is often disregarded in reports on HER-catalyst systems.[a] Dr.

Enhancing the CO2 Electroreduction of Fe/Ni‐Pentlandite Catalysts by S/Se Exchange

“…Notably, the substitution of sulfur for selenium in the Fe/Ni‐pentlandite lattice results in insignificant changes to the ECSA, ranging from 0.0054 mF cm −2 ( Se‐5 ) to 0.0071 mF cm −2 ( Se‐3 ), across the investigated catalysts. This minimal effect of the S/Se exchange on the ECSA is also in good accordance to comparable CO 2 RR investigations employing sulfoselenides and suggests a similar electrode surface area . During electrolysis, the ECSA of the investigated electrode increases for all compounds.…”

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

“…Nevertheless, a critical concern regarding materials development in many research efforts is still the use of a laborious trial and error strategy, which makes systematic understanding of the behavior of the materials complex. Moreover, the catalytic properties of the active materials themselves are inherently different from those of the fabricated electrodes involving nanostructuring or additives . This difference can be misleading and often brings discrepancy between reported results.…”

“…The high electronic conductivity of transition metal chalcogenides (TMCs) compared to metal oxides renders them a highly efficient, inexpensive and robust alternative to metal oxides and competitive to noble metals in OER and ORR catalysis , . In addition, TMCs, especially pentlandites, have other important characteristics including chemical stability in acidic and alkaline media and thus corrosion‐resistance, robustness and variable electronic structure . These properties render TMCs promising catalytically active materials.…”

“…These properties render TMCs promising catalytically active materials. Initially, such metal chalcogenides have been recognized as inexpensive, efficient HER catalysts , , . Interestingly, a hand‐full of metal chalcogenides exhibited excellent activity towards OER.…”

Sustainable and rapid preparation of nanosized Fe/Ni-pentlandite particles by mechanochemistry

“…15 This widespread interest can be attributed to the chemically robust nature of pentlandites, its pseudo-metallic conductivity as well as their large exibility of stoichiometric compositions. 16 Despite of the promising properties of pentlandite-type materials, their widespread and large-scale application is severely restricted by the currently employed synthetic strategies for their generation. Commonly, pentlandites are synthesized by high-temperature (ca.…”