Morphological variation of highly porous Ni–Sn foams fabricated by electro-deposition in hydrogen-bubble templates and their performance as pseudo-capacitors

•Highly porous dendritic Ni–Sn foams were fabricated by electro-deposition.•Various morphologies have been observed with different process conditions of temperature.•Even after 5000 cycles of charge–discharge, the specific capacitance loss of the electrodes is only about 7–9% of its maximum. Ni–Sn alloy foams with different morphologies for pseudo-capacitor applications have been prepared by electro-deposition involving a hydrogen evolution reaction. The morphology depends upon the composition of electrolytes and the electro-deposition temperature. Among the several different structures of Ni–Sn foams, one that has been prepared at 45°C represents the best electro-chemical performance of 1313Fg−1 at 1Ag−1 and it retained up to 91% of its initial performance even after 5000 cycles of charge–discharge. This Ni–Sn foam has a planar dendrite structure with bundles of flower-like tubes, providing highly porous foam with an extremely large surface area.