Low-temperature routes to early transition-metal nitrides

Transition Metal Pnictide Synthesis: Self Propagating Reactions Involving Sodium Arsenide, Antimonide and Bismuthide

“…elemental arsenic. All the transition metal halides studied react with N a3As to form metal arsenides, whereas analogous studies o f Li3N and MCI* found that a dividing line in reactivity was ob served with the early transition metal halides form ing metal nitrides and the later transition metal halides being reduced to the metal [6]. This diffe rence could be due to the greater therm al stability of arsenides com pared with nitrides o f the latter transition metals.…”

“…A trend is observed down the pnictogen group toward a reductive recom bination type reaction mechanism rather than metathesis. The use of Li3N with MC1V to yield metal nitrides [6,14] cannot involve recom bination o f the elements as nitrogen would not tend to remain in the reaction mixture and the N 2 pressures reached would not be sufficient to favour nitride formation. This and previous [6,7,14,15] work has indicated that ni trides, phosphides and arsenides form readily, whilst antimonides and especially bismuthides have a greater tendency to yield metal and pnictogen.…”

“…The use of Li3N with MC1V to yield metal nitrides [6,14] cannot involve recom bination o f the elements as nitrogen would not tend to remain in the reaction mixture and the N 2 pressures reached would not be sufficient to favour nitride formation. This and previous [6,7,14,15] work has indicated that ni trides, phosphides and arsenides form readily, whilst antimonides and especially bismuthides have a greater tendency to yield metal and pnictogen. The exception to this rule is with nitrides, where the low thermal stability of some nitrides re sults in thermal decomposition to metal and nitro gen [6].…”

“…Bonneau et al [4] have extended the idea to solid state metathesis (SSM) reactions, which are extremely exothermic and often rapid (2 -3 seconds), producing a bril liant flash of light and sublimed co-products. This technique has been used to synthesise a range of materials including layered transition metal di- We have applied SSM methods to the synthesis of transition metal and lanthanide oxides, nitrides and phosphides [5][6][7][8], In this paper we investigate the applicability of these methods to the synthesis of transition metal arsenides, antimonides and bis muthides and show that transition metal arsenides and some antimonides can be made, with reasona ble purity, with great saving in energy and time compared with traditional methods.…”

Solvothermal synthesis and electrochemical charge storage assessment of Mn3N2

“…6 Mn4N has been obtained from the solid state metathesis reactions of MnCl2 with NaN3 30 or Ca3N2, 31 and from MnI2 with Li3N, 32 and similar exchange reactions have been used to make crystals of Mn6N5 and Mn3N2 from MnI2 and NaNH2 in ammonia at 6 KBar and 400 to 600 °C. 33 Mn3N2 has also been prepared by solid state reaction of MnCl2 with LiNH2 followed by pyrolysis of the product in ammonia.…”