Hierarchically Porous Co/Co_xM_y (M = P, N) as an Efficient Mott–Schottky Electrocatalyst for Oxygen Evolution in Rechargeable Zn–Air Batteries

Small, Journal Year: 2019, Volume and Issue: 15(28)

Published: May 29, 2019

Abstract Tailoring composition and morphology of electrocatalysts is great importance in improving their catalytic performance. Herein, a salt‐templated strategy proposed to construct novel multicomponent Co/Co x M y (M = P, N) hybrids with outstanding electrocatalytic performance for the oxygen evolution reaction (OER). The obtained present porous sheet‐like architecture consisting many hierarchical secondary building‐units. synthetic depends on facile effective dissolution–recrystallization–pyrolysis process under NH 3 atmosphere precursors, which does not involve any surfactant or long‐time hydrothermal pretreatment. That different from conventional methods synthesis nitrides/phosphides. Benefitting unique composition/structure‐dependent merits, as typical Mott–Schottky electrocatalyst exhibit good OER an alkaline medium compared counterparts, evidenced by low overpotential 334 mV at 10 mA cm −2 small Tafel slope 79.2 dec −1 , well superior long‐term stability. More importantly, +Pt/C achieves higher voltaic efficiency several times longer cycle life than RuO 2 catalysts rechargeable Zn–air batteries. It envisioned that work can provide new avenue development sustainable energy storage.

Language: Английский

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Trifunctional of Phosphorus-Doped NiCo₂O₄ Nanowire Materials for Asymmetric Supercapacitor, Oxygen Evolution Reaction, and Hydrogen Evolution Reaction

ACS Applied Materials & Interfaces, Journal Year: 2019, Volume and Issue: 12(2), P. 2763 - 2772

Published: Nov. 20, 2019

Nowadays, transition-metal oxides are regarded as the most potential materials for supercapacitor and electrocatalyst. However, poor electrical conductivity insufficient active sites limited their development in various fields. Herein, we report method of phosphorous-doped NiCo2O4 (named P-NCO) prepared by two-step strategy: nanostructure is grown on nickel foams hydrothermal treatment subsequently phosphatized a tube furnace. Successfully, rich oxygen vacancies P element introduced into structure obviously improve conductivity, resulting P-NCO NWs/NF material shows an ultrahigh specific capacitance 2747.8 F g–1 at 1 A prominent rate performance (maintain 50% 100 g–1). Furthermore, assembled NWs/NF//RGO asymmetric has energy density 28.2 W h kg–1 even high power 7750.35 kg–1. After 10,000 cycles, still also 88.48% retention rate. As electrocatalyst, excellent hydrogen evolution reaction (55 mV 10 mA cm–2) (300 activities M KOH solution. This study provides effective strategy to prepare multifunctional materials.

Language: Английский

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Highly Selective Electrochemical Reduction of CO₂ to Alcohols on an FeP Nanoarray

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(2), P. 758 - 762

Published: Oct. 30, 2019

Electrochemical reduction of CO2 into various chemicals and fuels provides an attractive pathway for environmental energy sustainability. It is now shown that a FeP nanoarray on Ti mesh (FeP NA/TM) acts as efficient 3D catalyst electrode the reaction to convert alcohols with high selectivity. In 0.5 m KHCO3 , such NA/TM capable achieving Faradaic efficiency (FE CH3OH ) up 80.2 %, total FE CH3OH+C2H5OH 94.3 % at -0.20 V vs. reversible hydrogen electrode. Density functional theory calculations reveal FeP(211) surface significantly promotes adsorption toward CH3 OH owing synergistic effect two adjacent Fe atoms, potential-determining step hydrogenation process *CO.

Language: Английский

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Co₃O₄/Fe_0.33Co_0.66P Interface Nanowire for Enhancing Water Oxidation Catalysis at High Current Density

Advanced Materials, Journal Year: 2018, Volume and Issue: 30(45)

Published: Sept. 25, 2018

Abstract Designing well‐defined nanointerfaces is of prime importance to enhance the activity nanoelectrocatalysts for different catalytic reactions. However, studies on non‐noble‐metal‐interface electrocatalysts with extremely high and superior stability at current density still remains a great challenge. Herein, class Co 3 O 4 /Fe 0.33 0.66 P interface nanowires rationally designed boosting oxygen evolution reaction (OER) catalysis by partial chemical etching Co(CO ) 0.5 (OH)·0.11H 2 (Co‐CHH) Fe(CN) 6 3− , followed low‐temperature phosphorization treatment. The resulting exhibit very OER performance an overpotential only 215 mV 50 mA cm −2 Tafel slope 59.8 dec −1 in 1.0 m KOH. In particular, exhibits obvious advantage enhancing showing merely 291 800 much lower than that RuO (446 mV). remarkably stable negligible loss under overpotentials 200 240 150 h. Theoretical calculations reveal more favorable since electrochemical barrier optimally lowered active Co‐ O‐sites from interface.

Language: Английский

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Phosphorous-containing oxygen-deficient cobalt molybdate as an advanced electrode material for supercapacitors

Energy storage materials, Journal Year: 2018, Volume and Issue: 19, P. 186 - 196

Published: Oct. 30, 2018

Language: Английский

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