Developing cost-effective and high-performance oxygen evolution reaction(OER)electrocatalysts has become the intense research on pursuing emerging renewable energy conversion,in which exploring and investigating the i...Developing cost-effective and high-performance oxygen evolution reaction(OER)electrocatalysts has become the intense research on pursuing emerging renewable energy conversion,in which exploring and investigating the intrinsic nature of efficient and stable Cu Co spinel catalysts toward OER in alkaline media is highly desirable.Herein,Cu1–xCo2+xO4oxy-spinel nanoflakes are fabricated by a facile hydrothermal method with the oxidation of ammonia water.In the same condition,Cu1–xCo2+xS4thio-spinel nanospheres are formed without oxidation.In OER process,the as-obtained Cu1–xCo2+xO4nanoflakes and Cu1–xCo2+xS4nanospheres possess the anodic overpotential of 267 and 297 m V in alkaline media to drive the current density of 10 m A/cm^2,respectively,outperforming the state-of-the-art noble metal catalyst of RuO2.X-ray photoelectron spectroscopy analysis exhibits the higher ratio value of Co(Ⅲ)/Co(Ⅱ)in Cu1–xCo2+xO4than that in Cu1–xCo2+xS4,suggesting that the stronglyelectronegative oxygen efficiently predominates in regulating valence states of Co active sites in spinel structures.Remarkably,density functional theory simulation further reveals that the increased valence state of Co could accelerate the electron exchange between catalysts and oxygen adsorbates during electrocatalysis,thus contributing to the higher OER activity of Cu1–xCo2+xO4catalysts.This work provides deep insight regarding the significance of non-metal element(O and S)in Cu Co spinel structure catalysts,as well as presents a promising approach to exploit higher performance and grasp the mechanism of various non-noblemetal spinel catalysts for water oxidation.展开更多
基金the support from the National Natural Science Foundation of China(91750112,51801075)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX191591).D Rao gratefully acknowledges the support of Jiangsu Overseas Visiting Scholar Program for University Prominent Young and Mid-aged Teachers and Presidents.
文摘Developing cost-effective and high-performance oxygen evolution reaction(OER)electrocatalysts has become the intense research on pursuing emerging renewable energy conversion,in which exploring and investigating the intrinsic nature of efficient and stable Cu Co spinel catalysts toward OER in alkaline media is highly desirable.Herein,Cu1–xCo2+xO4oxy-spinel nanoflakes are fabricated by a facile hydrothermal method with the oxidation of ammonia water.In the same condition,Cu1–xCo2+xS4thio-spinel nanospheres are formed without oxidation.In OER process,the as-obtained Cu1–xCo2+xO4nanoflakes and Cu1–xCo2+xS4nanospheres possess the anodic overpotential of 267 and 297 m V in alkaline media to drive the current density of 10 m A/cm^2,respectively,outperforming the state-of-the-art noble metal catalyst of RuO2.X-ray photoelectron spectroscopy analysis exhibits the higher ratio value of Co(Ⅲ)/Co(Ⅱ)in Cu1–xCo2+xO4than that in Cu1–xCo2+xS4,suggesting that the stronglyelectronegative oxygen efficiently predominates in regulating valence states of Co active sites in spinel structures.Remarkably,density functional theory simulation further reveals that the increased valence state of Co could accelerate the electron exchange between catalysts and oxygen adsorbates during electrocatalysis,thus contributing to the higher OER activity of Cu1–xCo2+xO4catalysts.This work provides deep insight regarding the significance of non-metal element(O and S)in Cu Co spinel structure catalysts,as well as presents a promising approach to exploit higher performance and grasp the mechanism of various non-noblemetal spinel catalysts for water oxidation.