EDTA对活性炭的功能化处理及其对炭载Pd催化剂电催化性能的影响

摘要

采用乙二胺四乙酸(EDTA)对活性炭进行功能化处理，研究了其对表面基团、炭载Pd纳米粒子结构及Pd催化剂电催化性能的影响。傅里叶变换红外(FTIR)光谱和X射线光电子能谱(XPS)表征表明， EDTA处理在炭表面引入了含氮基团。 X射线粉末衍射(XRD)光谱、透射电镜(TEM)和电化学测试结果显示，活性炭经EDTA处理后，负载的Pd粒子粒径虽有所增大，但由于炭载体与Pd粒子相互作用的增强， Pd利用率增加，催化剂对甲酸氧化的活性和稳定性均显著提高。电化学阻抗谱(EIS)分析进一步揭示，甲酸在该催化剂电极上的电氧化反应具有较低的电荷传递电阻。%The effect of functionalization of activated carbon with ethylenediamine tetraacetic acid (EDTA) on surface functional groups, the structure of carbon-supported Pd nanoparticles, and the electrocatalytic performance of Pd catalysts were investigated. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) indicate that N-containing groups are introduced to the carbon surface via EDTA treatment. X-ray powder diffraction (XRD) spectra, transmission electron microscopy (TEM), and electrochemical measurements demonstrate that the electrocatalytic activity and stability for carbon-supported Pd catalysts were substantial y enhanced when the carbon support was treated with EDTA, although the Pd particles size increased slightly. The improved electrocatalytic performance may be due to enhanced interactions between the Pd particles and the carbon support, resulting in an improved Pd utilization. Electrochemical impedance spectrum analysis further reveals that the Pd catalyst on EDTA-treated carbon (Pd/C-E) displayed a lower charge-transfer resistance for the electro-oxidation reaction of formic acid.