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摘要: 本研究采用简易的碱性诱导自组装的方法制备了一种新型纳米Pd/Ni-Mo2C(2-6 nm)催化剂。该催化剂在碱性体系中对乙醇的电催化氧化展现出优异的性能。催化活性为2832.2 mA/mgPd,剩余电流密度为447.8 mA/mgPd,分别是质量分数10%商业Pd/C催化剂(1107.6和96.1 mA/mgPd)的2.6和4.7倍。Abstract: Herein, a new superfine nano Pd/Ni-Mo2C (2-6 nm) catalyst is developed via a facile, alkali-induced self-assembly strategy. The catalyst exhibits excellent performance towards ethanol electro-catalytic oxidation in alkaline system, with an activity of 2832.2 mA/mgPd and a residual current density of 447.8 mA/mgPd, which is 2.6 and 4.7 times enhancements compared with the commercial 10% Pt/C catalyst (1107.6 and 96.1 mA/mgPd).
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Key words:
- molybdenum carbide /
- nickel /
- alkali treatment /
- palladium /
- ethanol oxidation
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Figure 1 (a) Digital photo of the precursor powder, ((b), (c)) TEM images of Ni-MoO3 and ((d), (e)) TEM images of Ni-MoO3-T (the inset (in Figure 1(d)) shows its particle size distribution)
Figure 4 (a) TEM images of Pd/Ni-Mo2C-T, (b) particle size distribution of Pd/Ni-Mo2C-T, (c) elemental mapping images of Pd/Ni-Mo2C-T, (d) HRTEM images of Pd/Ni-Mo2C-T and (e) EDX analysis of Pd/Ni-Mo2C-T (the inset (in Figure 4(a)) shows the colour change of catalyst before and after loading palladium)
Figure 5 (a) Cyclic voltammograms (CV) of Pd/Ni-Mo2C, Pd/Ni-Mo2C-T and Pd/C in presence of 1 mol/L KOH and 1 mol/L C2H5OH with a scan rate of 50 mV/s at 30 ℃, (b) Chronoamperometry curves (CA) of the samples in presence of 1 mol/L KOH and 1 mol/L C2H5OH at -0.05 V for 1800 s at 30 ℃, (c) CV curves of Pd/Ni-Mo2C-T catalyst in presence of 1 mol/L KOH and 1 mol/L C2H5OH with different scan rates from 100 to 500 mV/s at 30 ℃ and (d) the relation of Ip-v1/2
Figure 6 (a) LSV curves of Pd/Ni-Mo2C catalyst in presence of 1 mol/L KOH and 1 mol/L C2H5OH at 298-313 K, (b) the relationship of lgi-1/T for Pd/Ni-Mo2C catalyst, (c) LSV curves of Pd/Ni-Mo2C catalyst in presence of 1 mol/L KOH and 1 mol/L C2H5OH at 298-313 K, and (d) the relationship of lgi-1/T for Pd/Ni-Mo2C-T catalyst
Table 1 Catalytic performance characteristics of different catalysts for ethanol electro-catalytic in alkaline condition
Catalyst Onset potential /V Peak current /(mA·mg-1 Pd) Residual current /(mA·mg-1 Pd) 10%Pd/C -0.561 1107.6 96.1 Pd/Ni-Mo2C -0.606 2232.3 124.9 Pd/Ni-Mo2C-T -0.628 2832.2 447.8 -
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