酸处理的碳作为阳极电催化剂用于直接抗坏血酸碱性膜燃料电池(英文)  

Acid Treated Carbon as Anodic Electrocatalysts toward Direct Ascorbic Acid Alkaline Membrane Fuel Cells

作　　者：陈禾木 邱晨曦[1] 丛媛媛[1] 刘会园 翟梓会[1] 宋玉江 CHEN He-mu;QIU Chen-xi;CONG Yuan-yuan;LIU Hui-yuan;ZHAI Zi-hui;SONG Yu-jiang(State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,China;Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,China)

机构地区：[1]大连理工大学,精细化工国家重点实验室&电化学工程实验室,化工学院,辽宁大连116024 [2]中国科学院大连化物所,辽宁大连116023

出　　处：《电化学》2018年第6期748-756,共9页Journal of Electrochemistry

基　　金：supported by National Key Research & Development Program of China (Gran No.2016YFB0101307);National Natural Science Fund of China (Grant Nos.21003114,21103163,21306188,21373211,and 21306187);Liaoning BaiQianWan Talents Program (Grant No.201519);Program fo

摘　　要：为改善电催化活性和亲水性,作者对商业碳黑(BP2000)进行了酸处理,获得了酸处理碳(ATC).通过X光电子能谱、红外光谱、热重和接触角测试的表征方法证明了酸处理在碳表面产生了丰富的含氧基团.本文首次利用紫外可见光谱测试了碱性条件抗坏血酸(AA)在空气中的化学氧化活化能,结果为37.1 kJ·mol^(-1).另外,利用交流阻抗谱对碱性条件下ATC作为电催化剂时AA的氧化反应的活化能进行了评价.碱性条件下,AA在单电池中有无ATC电催化剂层条件下的活化能分别为26.5和34.5 kJ·mol^(-1),活化能的降低表明ATC是一种有效的阳极电催化剂.作者将ATC应用于直接碱性膜AA燃料电池(DAAFCs)作为阳极电催化剂,并且对DAAFC中一系列参数进行了优化,包括催化剂在膜(CCM)或气体扩散层(CDM)上的喷涂方法、阳极电催化剂的载量、阳极电催化剂中碱性聚合物的比例.结果表明,采用CCM的膜电极制备方法、0.5 mg·cm^(-2)的ATC载量、25wt%的碱性聚合物添加比例时,DAAFCs单池的功率密度可达18.5 mW·cm^(-2),远高于使用商品PtRu/C(5 mW·cm^(-2))做阳极电催化剂的单池.在寿命测试中,使用溶解于1 mol·L^(-1)NaOH水溶液中的0.5 mol·L^(-1) AA作为燃料(流速15 m L·min^(-1)),DAAFCs单池的功率密度可以在25 min内维持在4 mW·cm^(-2)以上(75°C).In order to improve the hydrophilicity and electrocatalytic activity,commercial carbon black(BP 2000) was subjected to acid treatment to obtain acid-treated carbon(ATC).The generation of rich oxygen-containing groups on the surface of the ATC was proved by X-ray photoelectron spectra(XPS),Fourier transform-infra red spectra(FTIR),thermogravimetric analysis(TG) and contact angle measurement.UV-vis spectra were firstly recorded to calculate activation energy(Ea) of ascorbic acid(AA) chemical oxidation in alkaline conditions by oxygen in air and the Ea value was determined to be 37.1 kJ·mol-1.Additionally,electrochemical impedance spectra(EIS) were used to evaluate unprecedented Eae lectrochemof ATC as electrocatalysts toward ascorbic acid(AA)oxidation in alkaline media.The Eae lectrochemvalues of electrochemical oxidation in alkaline membrane electrode assembly(MEA)setup of a single cell without and with ATC as the anodic electrocatalysts were calculated to be 34.5 and 26.5 kJ·mol-1,respectively.The diminished Eae lectrochemsuggests that ATC does function as an effective anodic electrocatalyst.Furthermore,the ATC was applied in direct ascorbic acid alkaline membrane fuel cell(DAAFC) for the first time.We optimized a series of parameters for the fabrication of MEAs including catalyst coated membrane(CCM) or catalyst coated gas diffusion layer membrane(CDM),loading of anodic electrocatalyst,and ionomer content in the electrocatalyst slurry.It turned out that the CCM with the ATC loading of 0.5 mg·cm-2 and 25wt% ionomer reached a high power density of 18.5 mW·cm-2,which is higher than that of using Pt Ru/C as anodic electrocatalyst(less than 5.0 mW·cm-2).In addition,the DAAFC fed with 15 mL·min-1 of the fuel containing 0.5 mol·L-1 AA and 1 mol·L-1 NaOH aq.could stably hold a power density at 4 mW·cm-2 for 25 min.

关 键 词：直接碱性抗坏血酸燃料电池 碳 阳极电催化剂 活化能 酸处理 

分 类 号：O646[理学—物理化学]