Mesoporous Vanadium Nitride Synthesized by Chemical Routes

Abstract

Nanocrystalline vanadium nitride (VN) materials are synthesized by two different routes, namely, the urea route and the ammonia route, using various V 2 O 5 precursors obtained by citric acid-based sol-gel method. The VN nanomaterials obtained are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET method. The XRD patterns show the presence of pure cubic phase with line broadening. The lattice parameters were found to be 4.1266 and 4.1136 Å for the urea route and 4.1125 and 4.1120 Å for the ammonia route using V 2 O 5 precursors heat treated at 350 and 550 °C, respectively. The estimated crystallite sizes are found to be 9 and 7 nm for the urea route and 22 and 28 nm for the ammonia route using V 2 O 5 precursors synthesized at 350 and 550 °C, respectively. The SEM images show the presence of agglomerates having particle dimensions of 115 and (300 × 15) nm for the urea route and 111 and 68 nm for the ammonia route using V 2 O 5 precursors heat treated at 350 and 550 °C, respectively. The maximum BET surface area of 57 m 2 /g was obtained for VN sample synthesized by the urea route using V 2 O 5 precursors synthesized at 350 °C. The isotherms show typical Type IV with H2 hysteresis, which is characteristic of the mesoporous particles. The production of high-surface-area nitride materials has been correlated to synthetic procedure, precursor used and formation of mesopores in the material.

Tailoring the anion stoichiometry and oxidation kinetics of vanadium (oxy)nitride by the control of ammonolysis conditions

“…Previous studies suggested several routes for the synthesis of polycrystalline oxynitrides, such as the use of urea as a nitrogen source, 10,25 microwave synthesis, [26][27][28] hydrothermal synthesis, 29 high-temperature plasma routes, 30 mechanochemical synthesis under pressurized atmosphere, 31 the direct reaction of metal vanadium and nitrogen, and the direct ammonolysis of oxide precursors, aerogels, sulfides and metal amides. [32][33][34][35] In the current study, we focus on VON materials prepared by the ammonolysis route, involving the nitridation of vanadium pentoxide (V 2 O 5 ) by its reaction with gaseous ammonia (NH 3 ) at elevated temperature.…”

Plasma modification of vanadium oxynitride surfaces: Characterization by in situ XPS experiments and DFT calculations

“…The surface properties of vanadium oxynitride and related materials are of broad interest for many applications, including protective surface coatings, 1,2 supercapacitors, 3 heterogeneous catalysis, 4 and, recently, the nitrogen reduction reaction (NRR). [5][6][7] In these applications, the surface-specific N− −O interactions are often crucial.…”

Oxygen Electrocatalysis by Transition Metal Nitrides: History, Current Trends and Future Prospects

“…[28b, [43][44] For instance, Mishra et al studied the effect of ammonia annealing temperature on the particle size, BET surface area and pore size distribution of the generated nitrides. [45] Similarly, Panda et al investigated the effect of ammonia-assisted nitridation for differently-prepared WO 3 and CoWO 4 precursors on their crystal structure, surface area and pore texture. [46] Further, Saad et al synthesized mesoporous Ni 3 N and Ni 3 FeN via low-temperature thermal ammonia reduction of NiO and Ni 3 FeO x at 370 °C and 400 °C, respectively.…”

“…For instance, Mishra et al . studied the effect of ammonia annealing temperature on the particle size, BET surface area and pore size distribution of the generated nitrides [45] . Similarly, Panda et al .…”