Solvothermal synthesis and electrochemical charge storage assessment of Mn3N2

Abstract

η-Mn₃N₂ is produced using solvothermal reactions between MnCl₂ and LiNH₂ in benzene. At 350 °C nanocapsule structures are obtained, whereas at higher temperatures samples consisted of isotropic nanoparticulates. In aqueous KOH solution capacitances were up to 300 F g⁻¹ (2 mV s⁻¹, potential window 0.3 to −0.6 V vs. Hg/HgO), but capacitance fell to relatively low values on cycling. In lithium cells a reversible first cycle capacity of 600 mA h g⁻¹ was obtained, and this decayed to 340 mA h g⁻¹ after 50 cycles. In sodium cells a reversible first cycle capacity of 156 mA h g⁻¹ was obtained and was maintained well on cycling (127 mA h g⁻¹ in the 50^th cycle).