Enhanced Oxygen Evolution Reaction Electrocatalysis via Electrodeposited Amorphous ?-Phase Nickel-Cobalt Hydroxide Nanodendrite Forests
By Balram, Anirudh; Zhang, Hanfei; Santhanagopalan, Sunand
Published in ACS Applied Materials & Interfaces
2017
Abstract
We demonstrate an electrodeposition method to rapidly grow novel three-dimensional nanodendrite forests of amorphous ?-phase mixed nickel-cobalt hydroxides on stainless steel foil toward high performance electrocatalysis of the oxygen evolution reaction (OER). The proposed hydrogen bubble-templated, diffusion-limited deposition process leads to the unprecedented dendritic growth of vertically aligned amorphous metal hydroxides, induced by the controlled electrolysis of the tuned water content in the primarily alcohol-based deposition solution. The hierarchical nature of these binder-free, amorphous metal hydroxide deposits leads to their superhydrophilic nature and underwater superaerophobic behavior. The combination of all of these qualities leads to exemplary catalytic performance. When directly grown on planar stainless steel substrates, these nanoforests show high OER activity with overpotentials as low as ?255 mV to produce a current density of 10 mA cm