Cyanogel-derived nanoporous Sn–Fe–Ni ternary oxide network for high-capacity and long-life lithium storage

A novel type of ternary oxide nanohybrids, i.e., nanoporous Sn–Fe–Ni ternary oxide network, has been designed and constructed through facile thermal-oxidation route using a cyano-bridged Sn(IV)–Fe(II)–Ni(II) ternary metallic coordination polymer hydrogel (Sn–Fe–Ni cyanogel) as a precursor. The nanoporous ternary oxide network is assembled by numerous interconnected SnO2, Fe2O3, and NiO nanocrystal building blocks, and these oxide components are homogeneously distributed within the nanoporous network. The unique structural and compositional features are beneficial for enhanced lithium storage performances, and thus the nanoporous Sn–Fe–Ni ternary oxide network manifests much higher reversible capacities and markedly improved capacity retention in comparison with bare SnO2 nanocyrstals.