Highly stable 3D hierarchical manganese sulfide multi-layer nanoflakes with excellent electrochemical performances for supercapacitor electrodes

Transition metal sulfides are extensively studied as the watchful member of Faradic supercapacitive electrode materials because of their evidently enhanced electronic conductivity. Meanwhile, delicate development and manipulation of such novel nanostructured materials are required to achieve the desired electrochemical behaviors. Therefore, in this work a novel 3D hierarchical manganese sulfide (MS) multi-layer nanoflakes grown on Ni foam are designed and fabricated through the Kirkendall effect and applied as supercapacitors electrode. An advantage of such special 3D electrode architectures and unique compositional feature is in the fact that the as-prepared MS electrode presents greatly enhanced supercapacitive performances with ultrahigh specific capacity of 1.22 C cm−2 at 1 mV s−1 and fantastic cycling properties with the capacitance retention 100% after 1000 cycles. In addition, the electrochemical reaction of the MS electrode is a diffusion-controlled Faradaic redox process, while the diffusion coefficient is about 1.3 times larger than that of the manganese oxide (MO) electrode prepared under the same condition, suggesting the higher ion mobility of the MS electrode materials. These promising electrochemical behaviors demonstrate the great potential for application in high performance supercapacitors.