Transition metals (TMs) are ‘elements whose atoms have partially filled d-shell, or which can give rise to cations with an incomplete d-shell’. In TMs, the d-shell overlaps with next higher s-shell. Most of the TMs exhibit ...

Rechargeable Li-ion batteries and supercapacitors are the most promising electrochemical energy storage devices in terms of energy density and power density, respectively. Recently, nanostructured materials have gained ...