Synthesis Method and Thermodynamic Characteristics of Anode Material Li(3)FeN(2) for Application in Lithium-Ion Batteries

Li(3)FeN(2) material was synthesized by the two-step solid-state method from Li(3)N (adiabatic camera) and FeN(2) (tube furnace) powders. Phase investigation of Li(3)N, FeN(2), and Li(3)FeN(2) was carried out. The discharge capacity of Li(3)FeN(2) is 343 mAh g(−1), which is about 44.7% of the theoretic capacity. The ternary nitride Li(3)FeN(2) molar heat capacity is calculated using the formula C(p,m) = 77.831 + 0.130 × T − 6289 × T(−2), (T is absolute temperature, temperature range is 298–900 K, pressure is constant). The thermodynamic characteristics of Li(3)FeN(2) have the following values: entropy S(0)(298) = 116.2 J mol(−1) K(−1), molar enthalpy of dissolution Δ(d)H(LFN) = −206.537 ± 2.8 kJ mol(−1), the standard enthalpy of formation Δ(f)H(0) = −291.331 ± 5.7 kJ mol(−1), entropy S(0)(298) = 113.2 J mol(−1) K(−1) (Neumann–Kopp rule) and 116.2 J mol(−1) K(−1) (W. Herz rule), the standard Gibbs free energy of formation Δ(f)G(0)(298) = −276.7 kJ mol(−1).