Topological tailoring-induced Dirac cone in ultrathin niobium diboride nanosheets for electrocatalytic sulfur reduction reaction

Two-dimensional topological Dirac materials with novel electronic structures have attracted increasing attention in materials science, where the Weyl fermions can emerge in topological insulating multilayers with unusual quantum transport properties. However, their practical catalytic performance is seldom reported. Here, we design ultrathin niobium diboride (NbB2) nanosheets by utilizing topological electronic states to power catalytic activity. In the lithium-sulfur batteries, the stable topological surface states of NbB2 with high carrier mobility are a recipe for high-activity catalysts to spur the sluggish electrocatalytic sulfur reduction reaction, which originates from the Dirac cone electronic structure. Most remarkably, it delivers stable capacities with 1500 cycles under the 3.6 mA/cm2 (3 C), which is far superior to most electrode catalysts. The proposed functional Weyl and/or Dirac materials would have broad applications in other related fields such as the hydrogen evo-lution reaction, nitrogen reduction reaction, and energy conversion.

Automated summary

Ultrathin niobium diboride (NbB2) nanosheets with topological electronic states are designed to achieve high-activity catalysts, promoting sulfur reduction reaction. The catalyst exhibits stable capacity with 1500 cycles, surpassing most electrode catalysts, making it ideal for lithium-sulfur batteries. These functional Weyl and/or Dirac materials have broad applications in fields such as the hydrogen evolution reaction, nitrogen reduction reaction, and energy conversion.