Low-temperature synthesis and rational design of nitrides and oxynitrides for novel functional material development

Abstract

Nitrides and oxynitrides exhibit great potential for novel material development, since their electronic structures can be controlled by tuning the amounts of air-abundant nitrogen and oxygen elements therein. However, the above control methods still need to be developed, and the crystal and electronic structures of the produced nitrides/oxynitrides need to be understood. Herein, I summarize the recent progress in nitride and oxynitride synthesis, highlighting novel low-temperature nitridation of oxides by molten NaNH 2 , and attempt to rationalize the crystal and electronic structures of nitride and oxynitrides. Moreover, I describe how the catalytic activity of manganese oxynitrides in the oxygen reduction reaction can be enhanced by tuning their nitrogen content and thus their electronic structures.

Catalytic Performances of NiCuP@rGO and NiCuN@rGO for Oxygen Reduction and Oxygen Evolution Reactions in Alkaline Electrolyte

“…The nitrogen of NiCuN@rGO should be derived from the NH 4 NO 3 . [19] Figure 3d shows the TEM image of NiCuN@rGO, which clearly reveals that the particles are composed by agglomerated nanorods with an average diameter of 4.38 nm. Figure S3 also confirms the rGO sheet supported aggregated rod-like structure of NiCuN@rGO.…”

Composition, valence and oxygen reduction reaction activity of Mn-based layered double hydroxides

“…X-ray absorption spectroscopy is a powerful technique for examining the valence of metals in bulk states regardless of their electronic conductivity. This technique has sufficient energy resolution to estimate the valence and has been utilized to examine the correlation between electronic structures and catalytic activity in oxides and oxynitrides [6,7,15].…”

Precursor chemistry of metal nitride nanocrystals

“…One can rationalize the lower standard formation free energy for nitrides because of the high bond enthalpy of dinitrogen (941 kJ mol −1 ) versus dioxygen (500 kJ mol −1 ). 34,35 Another factor is the lower ionic character of metal nitrides since the enthalpy of formation of N 3− is much higher than for O 2− (2300 kJ mol −1 versus 700 kJ mol −1 ). 36 Only AlN and alkali(ne earth) metal nitrides are regarded as saline nitrides and they react quickly with water, releasing ammonia.…”