Amorphous/Crystalline Heterostructured Cobalt‐Vanadium‐Iron (Oxy)hydroxides for Highly Efficient Oxygen Evolution Reaction. Issue 43 (2nd October 2020)

• Record Type: Journal Article
• Authors: Kuang, Min; Zhang, Junming; Liu, Daobin; Tan, Huiteng; Dinh, Khang Ngoc; Yang, Lan; Ren, Hao; Huang, Wenjing; Fang, Wei; Yao, Jiandong; Hao, Xiaodong; Xu, Jianwei; Liu, Chuntai; Song, Li; Liu, Bin; Yan, Qingyu
• Is Part Of: Advanced energy materials. Volume 10:Issue 43(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-02
• Subjects: amorphous/crystalline -- binding energies -- electrocatalysis -- heterostructures -- oxygen evolution reaction; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202002215
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: The oxygen evolution reaction (OER) is a key process involved in energy and environment‐related technologies. An ideal OER electrocatalyst should show high exposure of active sites and optimal adsorption energies of oxygenated species. However, earth‐abundant transition‐metal‐based OER electrocatalysts still operate with sluggish OER kinetics. Here, a cation‐exchange route is reported to fabricate cobalt‐vanadium‐iron (oxy)hydroxide (CoV‐Fe0.28 ) nanosheets with tunable binding energies for the oxygenated intermediates. The formation of an amorphous/crystalline heterostructure in the CoV‐Fe0.28 catalyst boosts the exposure of active sites compared to their crystalline and amorphous counterparts. Furthermore, the synergetic interaction of Co, V, and Fe cations in the CoV‐Fe0.28 catalyst subtly regulates the local coordination environment and electronic structure, resulting in the optimal thermodynamic barrier for this elementary reaction step. As a result, the CoV‐Fe0.28 catalyst exhibits superior electrocatalytic activity toward the OER. A low overpotential of 215 mV is required to afford a current density of 10 mA cm −2 with a small Tafel slope of 39.1 mV dec −1, which outperforms commercial RuO2 (321 mV and 86.2 mV dec −1, respectively). Abstract : Amorphous/crystalline heterophased CoV‐Fe nanosheets with excellent catalytic performance in the oxygen evolution reaction (OER) are designed and prepared by a cation‐exchange method. The incorporation of Fe ions by a cation‐exchange method not only increases the number of active sites on a given electrode but also favors the adsorption of nucleophilic groups (hydroxyl group) on OER catalysts.