Synthesis Method and Thermodynamic Characteristics of Anode Material Li3FeN2 for Application in Lithium-Ion Batteries

Li3FeN2 material was synthesized by the two-step solid-state method from Li3N (adiabatic camera) and FeN2 (tube furnace) powders. Phase investigation of Li3N, FeN2, and Li3FeN2 was carried out. The discharge capacity of Li3FeN2 is 343 mAh g(-1), which is about 44.7% of the theoretic capacity. The ternary nitride Li3FeN2 molar heat capacity is calculated using the formula C-p,C-m = 77.831 + 0.130 x T - 6289 x T-2, (T is absolute temperature, temperature range is 298-900 K, pressure is constant). The thermodynamic characteristics of Li3FeN2 have the following values: entropy S-298(0) = 116.2 J mol(-1) K-1, molar enthalpy of dissolution Delta H-d(LFN) = -206.537 +/- 2.8 kJ mol(-1), the standard enthalpy of formation Delta H-f(0) = -291.331 +/- 5.7 kJ mol(-1), entropy S-298(0) = 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 Delta(f)G(298)(0) = -276.7 kJ mol(-1).

Automated summary

Li3FeN2 material was successfully synthesized through a two-step solid-state method and characterized in terms of phase analysis and properties. The discharge capacity of Li3FeN2 is 343 mAh g(-1), and its thermodynamic characteristics suggest good electrochemical performance.