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When NiO@Ni Meets WS2 Nanosheet Array: A Highly Efficient and Ultrastable Electrocatalyst for Overall Water Splitting
journal contribution
posted on 2017-12-07, 20:50 authored by Dewen Wang, Qun Li, Ce Han, Zhicai Xing, Xiurong YangThe development of
low-cost, high-efficiency, and stable bifunctional
electrocatalysts toward the hydrogen evolution reaction (HER) and
oxygen evolution reaction (OER) is of paramount importance for large-scale
water splitting. Here, we develop a new strategy for the first design
and synthesis of a NiO@Ni decorated WS2 nanosheet array
on carbon cloth (NiO@Ni/WS2/CC) composite. This composite
serves as a unique three-dimensional (3D) synergistic electrocatalyst
that not only combines the intrinsic properties of individual NiO@Ni
and WS2, but also exhibits significantly improved HER and
OER activities when compared to that of pure NiO@Ni and WS2. This electrocatalyst possesses Pt-like activity for HER and exhibits
better OER performance than that for commercial RuO2, as
well as demonstrating superior long-term durability in alkaline media.
Furthermore, it enables an alkaline electrolyzer with a current density
of 10 mA cm–2 at a cell voltage as 1.42 V, which
is the lowest one among all reported values to date. The excellent
performance is mainly attributed to the unique 3D configuration and
multicomponent synergies among NiO, Ni, and WS2. Our findings
provide a new idea to design advanced bifunctional catalysts for water
splitting.