Radially
Aligned Hierarchical Nickel/Nickel–Iron (Oxy)hydroxide Nanotubes
for Efficient Electrocatalytic Water Splitting
Zhihan Wu
Zhiqiang Wang
Fengxia Geng
10.1021/acsami.7b16953.s002
https://acs.figshare.com/articles/media/Radially_Aligned_Hierarchical_Nickel_Nickel_Iron_Oxy_hydroxide_Nanotubes_for_Efficient_Electrocatalytic_Water_Splitting/5938705
Designing
well-controlled hierarchical structures on micrometer and nanometer
scales represents one of the most important approaches for upgrading
the catalytic abilities of electrocatalysts. Although NiFe (oxy)hydroxide
has been widely studied as a water oxidation catalyst due to its high
catalytic capability and abundance, its structural manipulation has
been greatly restricted due to its inherent crystallographic stacking
feature. In this work, we report for the first time the construction
of a nanotube structure of NiFe (oxy)hydroxide with an inner Ni-rich
layer, which was radially aligned on a macroporous nickel foam. Such
a hierarchically structured material realized several crucial factors
that are essential for excellent catalytic behaviors, including abundant
catalytic sites, a high surface area, efficient ionic and electronic
transport, etc., and the designed catalyst exhibited competitive electrocatalytic
activity for reaction of not only oxygen evolution but also hydrogen
evolution, which is very rare. As a result, this novel material was
well-suited for the use as a bifunctional catalyst in an integrated
water-splitting electrolyzer, which could be even driven by a single
AA battery or a 1.5 V solar cell, outperforming a benchmark catalyst
of noble-metal ruthenium–platinum combinations and most state-of-the-art
electrocatalysts. The work provided important suggestions for the
rational modulation of catalysts with new structures targeted for
high-performance electrodes used in electrochemical applications.
2018-02-15 00:00:00
surface area
NiFe
water oxidation catalyst
novel material
electrochemical applications
benchmark catalyst
macroporous nickel foam
hydrogen evolution
nanotube structure
Efficient Electrocatalytic Water Splitting Designing well-controlled
1.5 V
electrocatalyst
bifunctional catalyst
Ni-rich layer
water-splitting electrolyzer
AA battery
nanometer scales
electrocatalytic activity
oxygen evolution