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Updated: Feb 13, 2026
Characterization of SiN Integrated Optical Phased Arrays on a Wafer-Scale Test Station
Published on: April 1, 2020
A wafer-scale 1 nm Ni(OH)2 nanosheet with superior electrocatalytic activity for the oxygen evolution reaction
Peng Tian1, Yanhao Yu, Xin Yin
1Department of Material Sciences and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA. xudong.wang@wisc.edu.
Abstract:
A wafer-scale 1.4 nm ultrathin Ni(OH)2 nanosheet was synthesized by ionic layer epitaxy. This free-standing Ni(OH)2 nanosheet was directly used to catalyze the oxygen evolution reaction (OER). At a current density of 10 mA cm-2, the overpotential reached 295 mV (vs. RHE) in Fe-rich 1 M NaOH. This 1.4 nm Ni(OH)2 nanosheet showed a very high turnover frequency of 5.47 s-1 and a mass activity of more than 2 × 104 A g-1 at an overpotential of 300 mV. Such a high electrocatalytic mass activity of the Ni(OH)2 nanosheet was more than 2 orders of magnitude higher than those of typical OER catalysts. The capability of producing wafer-scale nanometer-thick nanosheets offers a promising strategy to improve the mass efficiency of electrochemical catalysts, which is particularly valuable for preserving rare and precious catalyst materials.
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