Molybdenum Nitride Nanocatalyst Derived from Melamine and Polyoxometalate‐based Hybrid for Oxidative Coupling of Amines to Imines with Air

Abstract

Molybdenum nitride (Mo 2 N) is one of the most promising alternative catalysts for a wide range of Pt-catalyzed catalytic applications but is seldom investigated in oxidative coupling of amines to imines. A Mo 2 N-based nanocatalyst is successfully achieved by the hybridization of PMo 12 O 40 3À (PMo)-paired ionic pyridine-4-carboxylic acid (PC) and melamine (Mel), followed by calcination in N 2 . Melamine acts as an outstanding carburization and nitridation reagent that can convert into carbon nitride, and meanwhile the released N element react with Mo species in PMo to form Mo 2 N. The obtained catalyst PC-PMo-Mel-800 exhibits high activity and remarkable stability for the oxidative coupling of amines to imines under solvent-free and atmospheric conditions. This is the first case of Mo 2 N-catalyzed oxidative coupling reaction catalyst. The strategy reported herein for fabricating Mo 2 N may provide a significant and interesting approach to design more transition metal nitrides for wide catalytic applications.

Conductive Holey MoO2–Mo3N2 Heterojunctions as Job-Synergistic Cathode Host with Low Surface Area for High-Loading Li–S Batteries

“…Metallic MoN x (MoN, Mo 2 N, or Mo 3 N 2 ) is thought to be an excellent electrocatalyst owing to its electronic structure, which is similar to that of noble metals. , However, its effect on maintaining the capacity retention of Li–S batteries is limited . Most recently, the incorporation of V is suggested as an approach to modulate the electronic structure of MoN, leading to the improvement of polysulfide adsorption capability and cycling stability .…”

Pyrene‐Thiol‐modified Pd Nanoparticles on Carbon Support: Kinetic Control by Steric Hinderance and Improved Stability by the Catalyst‐Support Interaction

“…Typically, imines are produced by the condensation reaction between amines and aldehydes over Lewis acid catalysts, but aldehydes are toxic and unstable compounds [2–4] . As alternative greener approaches, an oxidative dehydrogenation of secondary amines to imines and a self‐coupling of primary amines with molecular oxygen have attracted much attention [5,6] . Although multiple types of homogeneous catalytic systems have been established, [7–11] the development of efficient heterogeneous catalysts for selective imine synthesis remains a challenging issue.…”

“…[2][3][4] As alternative greener approaches, an oxidative dehydrogenation of secondary amines to imines and a selfcoupling of primary amines with molecular oxygen have attracted much attention. [5,6] Although multiple types of homogeneous catalytic systems have been established, [7][8][9][10][11] the development of efficient heterogeneous catalysts for selective imine synthesis remains a challenging issue. Previous studies focused on the oxidation ability of Au nanoparticles (NPs), and several types of Au-based catalysts have been fabricated for the oxidative dehydrogenation of amines.…”

Freestanding Mo3N2 nanotubes for long‐term stabilized 2e− intermediate‐based high energy efficiency Li–CO2 batteries

“…Among these TMNs, Mo (4d 5 5s 1 ) characterizes the special half‐filled‐shell effect of valence electrons, which contributes to variable valences from low to high oxidation state. Moreover, the introduction of N helps to regulate the d‐electron structure, facilitating Mo–N‐rich catalytic behavior 11,16–18 . As one of molybdenum nitrides (MoN x ), Mo 3 N 2 is provided with the superiorities of electronic structure similar to noble metals, variability of oxidation states, excellent electrical conductivity, and mechanical strength, which shows outstanding performance in multifarious applications such as supercapacitor, 19,20 hydrogen evolution reaction, 21,22 Li–S battery, 23 and sodium‐ion storage 24 .…”

“…Moreover, the introduction of N helps to regulate the d-electron structure, facilitating Mo-N-rich catalytic behavior. 11,[16][17][18] As one of molybdenum nitrides (MoN x ), Mo 3 N 2 is provided with the superiorities of electronic structure similar to noble metals, variability of oxidation states, excellent electrical conductivity, and mechanical strength, which shows outstanding performance in multifarious applications such as supercapacitor, 19,20 hydrogen evolution reaction, 21,22 Li-S battery, 23 and sodium-ion storage. 24 The valence of Mo in Mo 3 N 2 tends to be +2, and each Mo 2+ is provided averagely with four valence electrons, thus showing richer delocalized electron density and reversible electron localization structure during the continuous electrochemical process.…”