Microflowers of Sn-Co-S derived from ultra-thin nanosheets for supercapacitor applications

•The novel broccoli-like 3D microflowers of Sn-Co-S are directly grown on Ni foam.•The 3D architecture of microflowers is composed of ultra-thin 2D nanosheets.•The optimized electrode exhibits excellent specific capacitance of 2319.3 F g-1.•The ASC device exhibits ultra-high energy density and superior cycling stability.