Tungsten doping role in structural modification and boosting electrochemical efficiency of Co(OH)2 dandelion assemblies.

• Novel dandelion assemblies of W-doped Co(OH) 2 nanostructures have been synthesized. • 5 % W-Co(OH) 2 exhibited amazing Faradaic redox reactions owing numerous active cites. • Specific capacitance (1051 Fg−1) of 5 % W-Co(OH) 2 increased twice of the undoped Co(OH) 2. • Tremendous cyclic stability with 92 % charge retention after 5000 cycles. • Power law (b = 0.71) exhibited the capacitive nature of dandelion assemblies for supercapacitors. Globally increasing energy demands and the drastic climate changes are pursuing cost-effective and environmental friendly energy storage option i.e. supercapacitors. Tungsten (W) doping in Co(OH) 2 has played an effective role in morphology changes along with improving its super capacitive properties. The 5 % W-doped Co(OH) 2 revealed perfectly dandelion assemblies having size range 3–4 µm and emerging wires with ∼10 nm diameter. These dandelion assemblies exhibited pseudocapacitive behavior and excellent specific capacitance 1000 Fg−1 at 1Ag−1 and 1051 Fg−1 at 5mVs−1 which is more than twice as compared to pristine Co(OH) 2. Power law (b = 0.71) exhibited capacitive nature of 5 % W-doped Co(OH) 2. High cyclic stability with 92 % charge retention have been achieved for 5000 cycles. This improved electrochemical performance is attributed to the high surface area with numerous active sites, amazing Faradaic redox reactions and excellent charge transfer rate. Hence, 5 % W-Co(OH) 2 dandelion assemblies are promising electrode materials for efficient supercapacitors. [ABSTRACT FROM AUTHOR]