利用X射线能量色散(EDS)谱、X射线衍射(XRD)谱、透射电子显微镜(TEM)和电化学等技术研究了在电解液中添加乙二胺四甲叉膦酸(EDTMP)对甲酸在Pd/C催化剂上电氧化性能的影响.结果表明,当EDTMP添加的浓度为0.5 mmol/L时,Pd/C催化剂对甲酸氧化的电催化活性和稳定性最好.这主要归结于吸附在Pd/C催化剂表面的EDTMP不但能通过基团效应降低CO的吸附量,还能抑制Pd/C催化剂催化甲酸分解的速率,从而减少了CO的毒化作用.但当EDTMP的浓度大于0.5 mmol/L时,吸附过多的EDTMP反而会占据Pd的活性位点,降低催化作用.%In order to improve the electrocatalytic performance of carbon supported Pd (Pd/C) anodic catalyst for formic acid oxidation in the direct formic acid fuel cell (DFAFC),the effect of ethylenediaminetetramethylene phosphonic acid (EDTMP) added into the electrolyte on the electrocatalytic performance of Pd/C catalyst for formic acid oxidation was investigated using the energy dispersive X-ray spectroscopy(EDS),X-ray diffraction (XRD) pattern,transmission electron microscopy (TEM) and electrochemical techniques.The Pd/C catalyst electrode in the electrolyte with O.5 mmol/L EDTMP displays the best electrocatalytic activity and stability for formic acid oxidation.This result is attributed to that the adsorbed EDTMP on the surface of Pd not only decreases the amount of adsorbed CO at the Pd/C catalyst electrode by the ensemble effect but also inhibits the decomposition of formic acid over the Pd/C catalyst to decrease the CO poisoning.However,when the concentration of EDTMP is higher than 0.5 mmol/L,overfull adsorbed EDTMP would occupy the active sites of Pd to decrease the electrocatalytic performance.
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