The performance of Ru-based nanoparticles(NPs)in the hydrogen evolution reaction(HER)relies on both their structural properties and the oxidation state of the metal.Herein,the versatility of the organometallic approac...The performance of Ru-based nanoparticles(NPs)in the hydrogen evolution reaction(HER)relies on both their structural properties and the oxidation state of the metal.Herein,the versatility of the organometallic approach for the synthesis of metal-based nanostructures is combined with thermal oxidation treatments to prepare carbon-nanotube(CNT)-supported Ru-containing nanomaterials for their use as electrocatalysts after dropcasting onto a glassy carbon rotating disk electrode.This strategy allowed access to a series of hybrid nanomaterials of different Ru/RuO_(2)compositions and different structural order.Linear sweep voltammetry experiments show that the relative disposition of the Ru/RuO_(2)phases,their interconversion under reductive turnover conditions and the degree of structural order affect the HER electrocatalytic performance of different materials.The electrode containing NPs consisting of a RuO_(2)core and metallic Ru at the surface outperforms that containing either pure RuO_(2)NPs or Ru NPs.Impedance spectroscopy studies and DFT calculations suggest that this catalytic activity enhancement arises from improved charge transport properties and from the structure of the exposed metallic Ru shell,which is partially oxidized and highly amorphous.展开更多
Development of efficient and durable catalysts based on earth-abundant elements for oxygen evolution reactions(OER)is important for renewable energy storage and conversion technologies.Herein,we report the development...Development of efficient and durable catalysts based on earth-abundant elements for oxygen evolution reactions(OER)is important for renewable energy storage and conversion technologies.Herein,we report the development of a Cu nanoparticle-embedded N-doped carbon nanowire array on copper foam(Cu-N-C NA/CF)via carbonization of a Cu(TCNQ)(TCNQ=7,7,8,8-tetracyanoquinodimethane)nanoarray.As a 3D OER electrode,this Cu-N-C NA/CF shows high catalytic activity,needing an overpotential of 314 mV to drive a geometrical current density of 20 mA cm^(-2)in 1.0 M KOH.It also shows strong long-term electrochemical durability.This suggested that CuO nanoparticles as active species were in situ electrochemically converted from Cu nanoparticles and stably dispersed in the carbon matrix during electrocatalysis.展开更多
基金financially supported by the MICINN/FEDER projects PID2019-104171RB-I00,PID2020-112715GB-I00,PID2021-128197NA-I00 and TED2021-129237B-I00the Red Española de Supercomputación(RES)through QHS-2021-3-0016 project,the CNRS,the Univ.Toulouse III–Paul Sabatier and the GDRI HC3A Franco-Catalan action.
文摘The performance of Ru-based nanoparticles(NPs)in the hydrogen evolution reaction(HER)relies on both their structural properties and the oxidation state of the metal.Herein,the versatility of the organometallic approach for the synthesis of metal-based nanostructures is combined with thermal oxidation treatments to prepare carbon-nanotube(CNT)-supported Ru-containing nanomaterials for their use as electrocatalysts after dropcasting onto a glassy carbon rotating disk electrode.This strategy allowed access to a series of hybrid nanomaterials of different Ru/RuO_(2)compositions and different structural order.Linear sweep voltammetry experiments show that the relative disposition of the Ru/RuO_(2)phases,their interconversion under reductive turnover conditions and the degree of structural order affect the HER electrocatalytic performance of different materials.The electrode containing NPs consisting of a RuO_(2)core and metallic Ru at the surface outperforms that containing either pure RuO_(2)NPs or Ru NPs.Impedance spectroscopy studies and DFT calculations suggest that this catalytic activity enhancement arises from improved charge transport properties and from the structure of the exposed metallic Ru shell,which is partially oxidized and highly amorphous.
文摘Development of efficient and durable catalysts based on earth-abundant elements for oxygen evolution reactions(OER)is important for renewable energy storage and conversion technologies.Herein,we report the development of a Cu nanoparticle-embedded N-doped carbon nanowire array on copper foam(Cu-N-C NA/CF)via carbonization of a Cu(TCNQ)(TCNQ=7,7,8,8-tetracyanoquinodimethane)nanoarray.As a 3D OER electrode,this Cu-N-C NA/CF shows high catalytic activity,needing an overpotential of 314 mV to drive a geometrical current density of 20 mA cm^(-2)in 1.0 M KOH.It also shows strong long-term electrochemical durability.This suggested that CuO nanoparticles as active species were in situ electrochemically converted from Cu nanoparticles and stably dispersed in the carbon matrix during electrocatalysis.
