Bimodal Mesoporous Titanium Nitride/Carbon Microfibers as Efficient and Stable Electrocatalysts for Li-O2 Batteries

Nonprecious transition metal nitrides have attracted considerable attention as an alternative catalyst to noble metals for electrochemical reactions. Titanium nitride (TiN), in particular, is an interesting material that exhibits excellent thermal, chemical, and mechanical stability, electrical conductivity, and in particular electrocatalytic activity. TiN is often prepared by the nitridation of titanium oxide using gaseous ammonia or hydrazine as a nitrogen source. This high temperature synthesis, however, gives a material with low surface area, which is unfavorable for its application in heterogeneous electrocatalysis. The shape and size of the assembly, and thus the resulting g-CN materials, can be tailored simply by using different precipitation temperatures, solvents, and comonomers. Furthermore, the assembly develops unique nanostructures during the polycondensation without losing the pristine macrostructures.