N-doped three-dimensional needle-like CoS₂ bridge connection Co₃O₄ core-shell structure as high-efficiency room...

The N-doped three-dimensional (3D) needle bridge connection core-shell structure N-CoS₂@Co₃O₄ synthesized in this work was prepared by simple hydrothermal and high-temperature vulcanization methods. The optimized N-CoS₂@Co₃O₄^-2 composite response to NO₂ is 62.3-100 ppm, a response time of 1.3 s, the recovery time of 17.98 s, the detection limit of 5 ppb and stability of as long as 10 weeks at room temperature (RT). Its excellent NO₂ sensing performance is attributed to the unique porous and bridge connection core-shell structure of the N-CoS₂@Co₃O₄^-2 with high specific surface area, interconnected internal channels, abundant exposed S edge active sites, and high catalytic performance promoted by N-doping. This simple manufacturing method of high-performance sensing materials paves the way for the design of N-doped bridge connection core-shell structures.