Title: Nickel based oxide film formed in molten salts for efficient electrocatalytic oxygen evolution

Author: Liang, XX (Liang, Xin Xin); Weng, W (Weng, Wei); Gu, D (Gu, Dong); Xiao, W (Xiao, Wei)

Source: JOURNAL OF MATERIALS CHEMISTRY A Volume: 7 Issue: 17 Pages: 10514-10522  

DOI: 10.1039/c9ta00997c Published: MAY 7 2019  

Abstract: Implementation of non-precious, active and durable catalysts towards the oxygen evolution reaction (OER) is a promising protocol addressing challenges in energy and environmental sustainability. Herein, a binderfree film composed of nickel ferrite is prepared by the anodic oxidation of a nickel alloy in molten salts. Merits of the electrochemical oxidation in molten salts are highlighted by the generation of the spinel NiFe2O4 film over the Ni-Fe-Cu substrate with full exposure of OER-active Fe species, absence of OERinert CuO species and good adhesion with the substrate. The prepared film electrode therefore exhibits higher electrocatalytic activity than the commercial IrO2/Ta2O5-Ti electrode towards the OER in an alkaline electrolyte. The overpotential to drive a current density of 10 mA cm-2 for the as-prepared electrode is only 326 mV, 27 mV less than that for the IrO2/Ta2O5-Ti electrode. Besides, the prepared nickel ferrite film also exhibits a low Tafel slope of 35.9 mV dec-1, an excellent turnover frequency (TOF) value of 0.85 s-1 at an overpotential of 300 mV and high stability after electrolysis at 50 mA cm-2 for 60 h in 1.0 M KOH. The present study highlights the potential for utilization of electrochemical oxidation of metallic substrates in molten salts for the fast preparation of high-quality oxide films with promising functionalities.

Document Type: Article

Language: English

Addresses of reprint authors: Xiao, W，Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Hubei, Peoples R China.

E-mail:  gabrielxiao@whu.edu.cn

Addresses: [Liang, Xin Xin; Weng, Wei; Xiao, Wei] Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Hubei, Peoples R China.

[Gu, Dong] Wuhan Univ, Inst Adv Studies, Wuhan 430072, Hubei, Peoples R China.

Impact factor：10.733