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Retracted: Colloidal Cobalt Phosphide Nanocrystals as Trifunctional Electrocatalysts for Overall Water Splitting Powered by a Zinc–Air Battery
Author(s) -
Li Hui,
Li Qi,
Wen Peng,
Williams Trey B.,
Adhikari Shiba,
Dun Chaochao,
Lu Chang,
Itanze Dominique,
Jiang Lin,
Carroll David L.,
Donati George L.,
Lundin Pamela M.,
Qiu Yejun,
Geyer Scott M.
Publication year - 2018
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.201705796
Subject(s) - materials science , phosphide , oxygen evolution , overpotential , chemical engineering , anode , water splitting , catalysis , battery (electricity) , cobalt , cathode , electrolysis , nanocrystal , electrolyte , inorganic chemistry , metal , nanotechnology , electrochemistry , electrode , chemistry , metallurgy , photocatalysis , biochemistry , power (physics) , physics , quantum mechanics , engineering
Abstract Highly efficient and stable electrocatalysts, particularly those that are capable of multifunctionality in the same electrolyte, are in high demand for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). In this work, highly monodisperse CoP and Co 2 P nanocrystals (NCs) are synthesized using a robust solution‐phase method. The highly exposed (211) crystal plane and abundant surface phosphide atoms make the CoP NCs efficient catalysts toward ORR and HER, while metal‐rich Co 2 P NCs show higher OER performance owing to easier formation of plentiful Co 2 P@COOH heterojunctions. Density functional theory calculation results indicate that the desorption of OH* from cobalt sites is the rate‐limiting step for both CoP and Co 2 P in ORR and that the high content of phosphide can lower the reaction barrier. A water electrolyzer constructed with a CoP NC cathode and a Co 2 P NC anode can achieve a current density of 10 mA cm −2 at 1.56 V, comparable even to the noble metal‐based Pt/C and RuO 2 /C pair. Furthermore, the CoP NCs are employed as an air cathode in a primary zinc–air battery, exhibiting a high power density of 62 mW cm −2 and good stability.