Titanium-supported nanoporous palladium catalyst (Pd/Ti) was prepared by a hydrothermal method using PdC12 as a precursor, ethylenediamine tetraacetic acid (EDTA) as a ligand, and formaldehyde as a reduction agent...Titanium-supported nanoporous palladium catalyst (Pd/Ti) was prepared by a hydrothermal method using PdC12 as a precursor, ethylenediamine tetraacetic acid (EDTA) as a ligand, and formaldehyde as a reduction agent. Complex Pd-EDTA^2- is favorable for the formation of Pd particles with nanoscale sizes. The electroactivity of the Pd/Ti catalyst towards the electroreduction of hydrogen peroxide in 1 mol/L NaOH solution was evaluated by voltammetric techniques. Both linear scan voltammetric and chronoamperometric data present significantly large steady-state reduction current density of the hydrogen peroxide electroreduction on the prepared Pd/Ti catalyst. The results show that the prepared Pd/Ti catalyst is an effective electrocatalyst for the electroreduction of hydrogen peroxide in alkaline media.展开更多
氧还原反应(ORR)是一个动力学缓慢的过程,而Pt或Pt基材料是其有效的电催化剂。本文通过构建合理的空间结构来大幅提高Pt的质量活性,并通过引入过渡金属共掺杂来提高Pt的本征活性,制备得到了Pt含量在4%(质量分数)以下的Pt-Co-Ni共掺杂的...氧还原反应(ORR)是一个动力学缓慢的过程,而Pt或Pt基材料是其有效的电催化剂。本文通过构建合理的空间结构来大幅提高Pt的质量活性,并通过引入过渡金属共掺杂来提高Pt的本征活性,制备得到了Pt含量在4%(质量分数)以下的Pt-Co-Ni共掺杂的空心碳球/管状碳复合催化剂Pt-Co-Ni/NHCS-TUC-600。ORR电化学活性测试表明,Pt-Co-Ni/NHCS-TUC-600在0.1 mol/LHClO_(4)中具有与商业Pt/C相当的起始电位(0.927 V vs RHE)和半波电位(0.867 V vs RHE),优于商业Pt/C的极限扩散电流密度(6.97 mA/cm^(2))。这些优异的ORR活性使得Pt-Co-Ni/NHCS-TUC-600具有广阔的应用前景,为低载量铂催化剂的研究与应用提供了新的可能。展开更多
In this paper,we synthesized cathode catalysts(PANI-PPYR,Fe/PANI-PPYR,Co/PANI-PPYR and Fe-Co/PANI-PPYR)with high performance oxygen reduction by using a simple heat treatment process.These catalysts were fabricated by...In this paper,we synthesized cathode catalysts(PANI-PPYR,Fe/PANI-PPYR,Co/PANI-PPYR and Fe-Co/PANI-PPYR)with high performance oxygen reduction by using a simple heat treatment process.These catalysts were fabricated by directly calcining the Fe and/or Co doped polyaniline(PANI)-polypyrrole(PPYR)composites.Their electrocatalytic activity for ORR both in acidic and in alkaline media was investigated by voltammetric techniques.Among the prepared catalysts,Co/PANI-PPYR presents the most positive ORR onset potential of 0.62 V(vs.SCE)in 0.5 mol/L H2SO4 solution or?0.09 V(vs.SCE)in 1 mol/L NaOH solution.In addition,the Co/PANI-PPYR catalyst shows the largest limiting-diffusion current density for ORR,which is 4.3 mA/cm2@0.2 V(vs.SCE)in acidic and 2.3 mA/cm2@?0.3 V(vs.SCE)in alkaline media.In acidic media,a four-electron reaction of ORR on the Co/PANI-PPYR and Fe/PANI-PPYR catalysts is more dominant than a two-electron reaction.In alkaline media,however,a four-electron and a two-electron mechanisms are co-present for the ORR on all the prepared catalysts.Co/PANI-PPYR catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media.展开更多
基金supported by the National Natural Science Foundation of China (No. 20876038)the Hunan Provincial Natural Science Foundation of China (No. 10JJ9003)the Planned Science and Technology Project of Hunan Province, China (No. 2009GK3084)
文摘Titanium-supported nanoporous palladium catalyst (Pd/Ti) was prepared by a hydrothermal method using PdC12 as a precursor, ethylenediamine tetraacetic acid (EDTA) as a ligand, and formaldehyde as a reduction agent. Complex Pd-EDTA^2- is favorable for the formation of Pd particles with nanoscale sizes. The electroactivity of the Pd/Ti catalyst towards the electroreduction of hydrogen peroxide in 1 mol/L NaOH solution was evaluated by voltammetric techniques. Both linear scan voltammetric and chronoamperometric data present significantly large steady-state reduction current density of the hydrogen peroxide electroreduction on the prepared Pd/Ti catalyst. The results show that the prepared Pd/Ti catalyst is an effective electrocatalyst for the electroreduction of hydrogen peroxide in alkaline media.
文摘氧还原反应(ORR)是一个动力学缓慢的过程,而Pt或Pt基材料是其有效的电催化剂。本文通过构建合理的空间结构来大幅提高Pt的质量活性,并通过引入过渡金属共掺杂来提高Pt的本征活性,制备得到了Pt含量在4%(质量分数)以下的Pt-Co-Ni共掺杂的空心碳球/管状碳复合催化剂Pt-Co-Ni/NHCS-TUC-600。ORR电化学活性测试表明,Pt-Co-Ni/NHCS-TUC-600在0.1 mol/LHClO_(4)中具有与商业Pt/C相当的起始电位(0.927 V vs RHE)和半波电位(0.867 V vs RHE),优于商业Pt/C的极限扩散电流密度(6.97 mA/cm^(2))。这些优异的ORR活性使得Pt-Co-Ni/NHCS-TUC-600具有广阔的应用前景,为低载量铂催化剂的研究与应用提供了新的可能。
基金supported by the National Natural Science Foundation of China(21376070,20876038)the Scientific Research Fund of Hunan Provincial Education Department(11K023)Hunan Provincial Natural Science Foundation of China(14JJ2096)
文摘In this paper,we synthesized cathode catalysts(PANI-PPYR,Fe/PANI-PPYR,Co/PANI-PPYR and Fe-Co/PANI-PPYR)with high performance oxygen reduction by using a simple heat treatment process.These catalysts were fabricated by directly calcining the Fe and/or Co doped polyaniline(PANI)-polypyrrole(PPYR)composites.Their electrocatalytic activity for ORR both in acidic and in alkaline media was investigated by voltammetric techniques.Among the prepared catalysts,Co/PANI-PPYR presents the most positive ORR onset potential of 0.62 V(vs.SCE)in 0.5 mol/L H2SO4 solution or?0.09 V(vs.SCE)in 1 mol/L NaOH solution.In addition,the Co/PANI-PPYR catalyst shows the largest limiting-diffusion current density for ORR,which is 4.3 mA/cm2@0.2 V(vs.SCE)in acidic and 2.3 mA/cm2@?0.3 V(vs.SCE)in alkaline media.In acidic media,a four-electron reaction of ORR on the Co/PANI-PPYR and Fe/PANI-PPYR catalysts is more dominant than a two-electron reaction.In alkaline media,however,a four-electron and a two-electron mechanisms are co-present for the ORR on all the prepared catalysts.Co/PANI-PPYR catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media.