Three-Dimensionally Ordered Macro/Mesoporous NbO/NbN Heterostructure as Sulfur Host for High-Performance Lithium/Sulfur Batteries.

The severe shuttle effect of soluble polysulfides hinders the development of lithium-sulfur batteries. Herein, we develop a three-dimensionally ordered macro/mesoporous (3DOM) NbO/NbN heterostructure, which combines the strong adsorption of NbO and remarkable catalysis effect of NbN by the promotion "adsorption-transformation" mechanism in sulfur reaction. Furthermore, the high electrocatalytic activity of NbN facilitates ion/mass transfer during the charge/discharge process. As a result, cells with the S-NbO/NbN electrode delivered outstanding cycling stability and higher discharge capacity than its counterparts. Our work demonstrates a new routine for the multifunctional sulfur host design, which offers great potential for commercial high-performance lithium-sulfur batteries.