Die lokale Oberflächenstruktur und ‐zusammensetzung bestimmt die Wasserstoffentwicklung an Eisen‐Nickelsulfiden

Abstract

Um leistungsfähigere Elektrokatalysatoren zu entwickeln, ist es notwendig,d en Einfluss der Oberflächenstruktur und -zusammensetzung von Materialien mit hoher lokaler Auflçsung besser zu verstehen. Dies trifft insbesondere auf die Entwicklung geeigneter Alternativen fürP latin bei der elektrokatalytischen Wasserstofferzeugung zu. Elektrochemische Rasterzellmikroskopie (scanning electrochemical cell microscopy, SECCM) wurdebenutzt, um die lokale elektrochemische Aktivitätd er Wasserstoffbildung an einkristallinen (111)-Oberflächen von Fe 4.5 Ni 4.5 S 8 ,e inem hochaktiven Elektrokatalysator fürd ie Wasserstofferzeugung, zu untersuchen. In Kombination mit strukturaufklärendenM ethoden zeigen wir, dass kleinste Veränderungen der chemischen Zusammensetzung die Aktivitätsignifikant verändern kçnnen. Somit stellen die auf der Nanoskala durchgeführten elektrochemischen Messungen, ergänzt mit lokalen strukturellen Messungen sowie Kenntnis der lokalen Zusammensetzung ein wichtiges Hilfsmittel fürd as rationale Design neuer Katalysatoren dar.

High‐Resolution Electrochemical Mapping of the Hydrogen Evolution Reaction on Transition‐Metal Dichalcogenide Nanosheets

“…The total number of the HER active S defect sites inside meniscus would be much less than that in bulk measurement. This difference of the overpotential was also discussed by Schuhmann and co‐workers . A numbers of small spots around the 1H‐MoS 2 , which side length of about 130 nm, were also identified as small size MoS 2 (Supporting Information, Figure S5).…”

Electrocatalysis as the Nexus for Sustainable Renewable Energy: The Gordian Knot of Activity, Stability, and Selectivity

“…[46] Small variations in the surface structure and composition of a single Fe 4.5 Ni 4.5 S 8 nanoparticle resulted in a change in the HER activity that could be discerned by SECCM. [47] In a study of the HER on holey graphene (G) by SECCM, the edges were identified to be the most active sites. The HER increased upon doping G with N or P and was highest when G was co-doped with both N and P (NP).…”

Nanoscale Visualization and Multiscale Electrochemical Analysis of Conductive Polymer Electrodes

“…As explored herein, the nanoscale spatial-heterogeneity arising from phase segregation in polymer blend electrodes can be addressed most powerfully using the local electrochemical technique scanning electrochemical cell microscopy (SECCM) 27,28 to fully understand the relationship between local chemical composition and electrochemical reactivity. 29,30 Indeed, this approach has been previously demonstrated with many classes of (electro)material, including: sp 2 carbon electrodes (e.g., graphite, nanotubes and graphene), 31 battery materials, 32 electrocatalysts (e.g., transition metal dichalcogenides, [33][34][35] iron nickel sulfides, 36 polycrystalline metals [37][38][39] etc.) and corroding metals.…”