A Single‐Source Precursor Approach to Self‐Supported Nickel–Manganese‐Based Catalysts with Improved Stability for Effective Low‐Temperature Dry Reforming of Methane

Abstract

Self‐supported nickel–manganese‐based catalysts were synthesized from heterobimetallic nickel manganese oxalate precursors via a versatile reverse micelle approach. The precursors were subjected to thermal degradation (400 °C) in the presence of synthetic air to form respective metal oxides, which were treated under hydrogen (500 °C) to form Ni2MnO4–O2–H2, Ni6MnO8–O2–H2 and NiO–O2–H2. Similarly, the precursors were also treated directly under hydrogen at the same temperature to form Ni2MnO4–H2 and Ni6MnO8–H2. The catalysts were extensively investigated by PXRD, SEM, TEM, XPS and BET analyses. The resulting catalysts were applied for dry reforming of methane (DRM) and exhibit better stability and resistance to coking than coprecipitated catalysts. Further, we show that addition of manganese, which is not an active catalyst for DRM alone, to nickel has a significant promotion effect on both the activity and stability of DRM catalysts, and a Ni/Mn ratio lower than 6:1 enables optimized activity for this system.

A Molecular Approach to Manganese Nitride Acting as a High Performance Electrocatalyst in the Oxygen Evolution Reaction

“…[2] Thus,c onsiderable research efforts have been undertaken to the betterment of non-precious metal-based OER electrocatalysts employing earth-abundant metals. [3][4][5][6][7] In this regard, Mn-based materials have drawn much attention as potential OER catalysts inspired by the Mn-containing oxygen evolving complex (OEC) in the natural photosystem II (PSII). Accordingly,v arious crystalline and amorphous MnO x materials have been synthesized and tested in the OER in the last few years.…”

“…[19] Furthermore,t his corrosion leads into an active amorphous MnO x layer at the surface of Mn 3 N 2 particles by oxidizing Mn 2+ /Mn 3+ to Mn 3+ /Mn 4+ .Such Mn 3+ (in t 2g 3 e g 1 configuration) assisted by Mn 4+ are known to provide Jahn-Teller distorted Mn À Ob onds for binding O À Ow ith appropriate strength to facilitate OER and often documented as the real active sites. [3][4][5][6][7] Moreover,t he metallic character of Mn 3 N 2 also functions as ahighly conductive layer between the surface of the catalyst and electrode substrate providing faster charge transfer capability by controlling the OER activity,w hich is rather anotable drawback in the case of merely MnO x -based systems. [31]…”

Nano‐Sized Inorganic Energy‐Materials by the Low‐Temperature Molecular Precursor Approach

“…[14l] More recently,wehave also focused our attention on the fabrication of new multicomponent functional materials using the bottom-up approach, employing the same SSPs for applications in heterogeneous chemocatalysis. [15] Following as imple one pot soft templating approach, we have produced yolk@shell (M NP @ITO TR ;M= Au and/or Ag) nanocomposites for electrocatalytic oxidation of carbon monoxide (CO) and glucose. [16] Likewise,s upported NiO nanoparticles were prepared by impregnation of mesoporous silica SBA-15 with amolecular [Ni 4 O 4 ]cubane-like SSP,and successfully utilized this material for the catalytic dry reforming of methane (DRM).…”

“…[35a, 41] TheReisner group has used two molecular SSPs (e.g. [Ti 2 (OEt) 9 (NiCl)] 2 (termed TiNi SSP )a nd [Ti 4 O(OEt) 15 (CoCl)] (termed TiCo SSP )) that readily decomposes to form transition-metal doped titania coatings with tunable electronic and photochemical properties,when subjected to hydrolysis.The successful utilization of these SSPs in water-splitting catalysis is ad irect reflection of their facile hydrolysis to form amorphous TiO 2 as aprotective coating, as well as pre-catalytic Ni or Co species,w hich are among the best-known non-noble metal based HER and OER catalysts in alkaline conditions.T hey have applied the SSP approach to awide range of photo-corrodible electrodes, such as fluorine-doped tin oxide (FTO),W O 3 ,B iVO 4 and p-Si. Thep assivated electrodes display ap romising stability under ambient operating conditions.Therefore,this work sets an impressive benchmark for OER photoanodes and HER photocathodes constructed solely from earth-abundant materials that operate efficiently under neutral-alkaline conditions.…”

Nanoskalige anorganische Energiematerialien aus molekularen Vorstufen bei tiefer Temperatur

“…So beobachteten wir unter Verwendung von ITO TR schnellen und effizienten Elektronentransfer zwischen ITO und dem darauf immobilisierten Metalloenzym Cytochrom‐ C ‐Oxidase . In jüngerer Zeit haben wir unsere Aufmerksamkeit der Herstellung neuer funktioneller Mehrkomponentenmaterialien durch den Bottom‐up‐Ansatz zugewandt und dabei dieselben SSPs für Anwendungen in der heterogenen Chemokatalyse verwendet . Unter Verwendung einer einfachen Eintopftemplatierungsstrategie haben wir Yolk@Shell‐Nanokomposite (M NP @ITO TR ; M=Au und/oder Ag) für die elektrokatalytische Oxidation von Kohlenmonoxid (CO) und Glucose erzeugt .…”