TY - JOUR
T1 - Active Edge Sites Engineering in Nickel Cobalt Selenide Solid Solutions for Highly Efficient Hydrogen Evolution
AU - Xia, Chuan
AU - Liang, Hanfeng
AU - Zhu, Jiajie
AU - Schwingenschlögl, Udo
AU - Alshareef, Husam N.
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: Research reported in this publication was supported by King Abdullah University of Science and Technology (KAUST). The authors wish to thank the staff of the Imaging and Characterization Laboratory at KAUST, especially Dr. Chao Zhao for his help with the TEM analysis.
PY - 2017/1/6
Y1 - 2017/1/6
N2 - An effective multifaceted strategy is demonstrated to increase active edge site concentration in NiCoSe solid solutions prepared by in situ selenization process of nickel cobalt precursor. The simultaneous control of surface, phase, and morphology result in as-prepared ternary solid solution with extremely high electrochemically active surface area (C = 197 mF cm), suggesting significant exposure of active sites in this ternary compound. Coupled with metallic-like electrical conductivity and lower free energy for atomic hydrogen adsorption in NiCoSe, identified by temperature-dependent conductivities and density functional theory calculations, the authors have achieved unprecedented fast hydrogen evolution kinetics, approaching that of Pt. Specifically, the NiCoSe solid solutions show a low overpotential of 65 mV at -10 mV cm, with onset potential of mere 18 mV, an impressive small Tafel slope of 35 mV dec, and a large exchange current density of 184 μA cm in acidic electrolyte. Further, it is shown that the as-prepared NiCoSe solid solution not only works very well in acidic electrolyte but also delivers exceptional hydrogen evolution reaction (HER) performance in alkaline media. The outstanding HER performance makes this solid solution a promising candidate for mass hydrogen production.
AB - An effective multifaceted strategy is demonstrated to increase active edge site concentration in NiCoSe solid solutions prepared by in situ selenization process of nickel cobalt precursor. The simultaneous control of surface, phase, and morphology result in as-prepared ternary solid solution with extremely high electrochemically active surface area (C = 197 mF cm), suggesting significant exposure of active sites in this ternary compound. Coupled with metallic-like electrical conductivity and lower free energy for atomic hydrogen adsorption in NiCoSe, identified by temperature-dependent conductivities and density functional theory calculations, the authors have achieved unprecedented fast hydrogen evolution kinetics, approaching that of Pt. Specifically, the NiCoSe solid solutions show a low overpotential of 65 mV at -10 mV cm, with onset potential of mere 18 mV, an impressive small Tafel slope of 35 mV dec, and a large exchange current density of 184 μA cm in acidic electrolyte. Further, it is shown that the as-prepared NiCoSe solid solution not only works very well in acidic electrolyte but also delivers exceptional hydrogen evolution reaction (HER) performance in alkaline media. The outstanding HER performance makes this solid solution a promising candidate for mass hydrogen production.
UR - http://hdl.handle.net/10754/622795
UR - http://onlinelibrary.wiley.com/doi/10.1002/aenm.201602089/full
UR - http://www.scopus.com/inward/record.url?scp=85008394577&partnerID=8YFLogxK
U2 - 10.1002/aenm.201602089
DO - 10.1002/aenm.201602089
M3 - Article
SN - 1614-6832
VL - 7
SP - 1602089
JO - Advanced Energy Materials
JF - Advanced Energy Materials
IS - 9
ER -