




下载本文档
版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
1、Experimental class on “ Fuel Cell and ElectrochemistryExperiment setupEquipment: CHI760D electrochemical stationThree electrode system. WE: CE: RE: Saturated Calomel ElectrodeSolution: 1 .0 X 10-3mol/L K 3 Fe (CN) 6 + 0,1M KClLab reportPlot curves of LSV curve, and describe why current changes with
2、sweeping voltage?Reason: Voltage is a driving force to an electrode reactions, it is concerned with the equilibrium of electron transfer at electrode surface. As the altering of applied voltage, the Fermi-level is raised (or lowered), which changing the energy state of the electrons. Making the over
3、all barrier height (ie activation energy) alter as a function of the applied voltage. In this reaction, when voltage is 0.6V, there is no electron transfer, so the current is zero.With the voltage to the more reductive values, the current increases. When the diffusion layer has grown sufficiently ab
4、ove the electrode so that the flux of reactant to the electrode is not fast enough to satisfy that required by Nernst Equation. The peak is obtaining. When the reaction continued, it would get a situation that there will be a lower reactant concentration at the electrode than in bulk solution, that
5、is, the supply of fresh reactant to the surface decreased, so current decreases.Plot the curves of CV curves with different scan rate;0.00006H-600mv/s G-500mv/s F-400mv/s E-300mv/s D-200mv/s C-100mv/s B- 50 mv/s A- 20 mv/s0.000040.000020.00000-0.00002-0.000040.60.40.20.0-0.2-0.4araR nacs0.00006H-600
6、mv/s G-500mv/s F-400mv/s E-300mv/s D-200mv/s C-100mv/s B- 50 mv/s A- 20 mv/s0.000040.000020.00000-0.00002-0.000040.60.40.20.0-0.2-0.4araR nacsPotential/VScan rate (mV/s)2050100200300400500600Peak current (uA)Ipc8.33613.1718.5025.9631.5436.1740.2343.95Ipa-8.263-13.01-18.19-25.26-30.50-34.88-38.68-42.
7、12Ratio of Peak current1.0091.0121.0171.0281.0341.0371.0401.043Peak voltag E(V)V10.1710.1890.1910.1900.1870.1860.1830.183V20.2420.2550.2590.2620.2620.2620.2620.262Peak voltage difference (mV)7166687275767979From the CV curves, fill the table3)4) According to the result, describe why curves shows cer
8、tain trend, and how peak current and peak voltage difference change with scan rate?Answer: From above data and curve, we can obtain:At a fixed scan rate : (1).from initial positive voltage to more reductive values, the current beginto flow, then reach a peak ipc and decrease eventually. (2).when vol
9、tage moves back, the equilibrium positions gradually converting electrolysis product (Fe 2+) back to reactant (Fe 3+), the current flow is from the solution species back to the electrode and so occurs in the oppositesense to the forward. The process has another current peak ipa. It has same reason o
10、f linear sweep voltammetry.At different scan rate, the ratio of peak current ip c/ip a is about equal to 1 (1.009 1.043).At different scan rate, the position of peak voltage do not alter greatly C Ep is about a constant (66-79).mV/s)20501002003004005006001/2V(mV/s) 1/24.4727.0711014.14217.3212022.36
11、124.495Ip (uA)8.33613.1718.5025.9631.5436.1740.2343.95Ep(V)0.1710.1890.1910.1900.1870.1860.1830.183Ep (mV)7166687275767979 Ip-V1/2Figure 1: Peak current VS radical sign of scan rate Interpretation:It is apparent that the peak current is linear to radical sign of scan rate, whichsatisfy this equation
12、: ip = kv 1/2Co.Reason:This can be rationalised by considering the size of the diffusion layer and the time taken to record the scan. Clearly the linear sweep voltammogram will take longer to record as the scan rate is decreased. Therefore the size of the diffusion layer above the electrode surface
13、will be different depending upon the voltage scan rate used. In a slow voltage scan the diffusion layer will grow much further from the electrode in comparison to a fast scan. Consequently the flux to the electrode surface is considerably smaller at slow scan rates than it is at faster rates. As the
14、 current isproportional to the flux towards the electrode, the magnitude of the current will be lower at slow scan rates and higher at high rates.Ep-VFigure 2: Peak potential VS scan rateEp-v1601200 -|1|1|1|-|1-i0100200300400500600700v (mV/s)Figure 3: the change of Peak potential VS scan rateInterpretation: Figure 2: shows that the position of the peak current occurs at the same voltage.Figure 3: shows the Pea
温馨提示
- 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
- 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
- 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
- 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。
最新文档
- 单位资产划转协议书
- 2025年03月浙江台州市黄岩区事业单位公开招聘工作人员100人笔试历年典型考题(历年真题考点)解题思路附带答案详解
- 2025年03月国家卫生健康委统计信息中心公开招聘人才派遣1人笔试历年典型考题(历年真题考点)解题思路附带答案详解
- 三维多向整体编织物项目安全风险评价报告
- 中国矿业大学《现代汉语A》2023-2024学年第二学期期末试卷
- 批发服务项目安全风险评价报告
- 郑州美术学院《运动技能学习与控制》2023-2024学年第一学期期末试卷
- 湖南大学《英语听力1》2023-2024学年第一学期期末试卷
- 江西农业大学《广告创意与策划》2023-2024学年第二学期期末试卷
- 上海兴伟学院《TracePro光路设计》2023-2024学年第二学期期末试卷
- 人工智能技术与知识产权保护
- 2025-2030便利店行业市场发展现状及发展前景与投资研究报告
- 信息技术与小学教育教学融合
- 提高教学管理质量校长讲话:“2574”工作实施思路!即两大抓手五项重点任务七个落实环节四个质量目标
- 清理报废渔船合同范本
- 《基于西门子S7-1200PLC的四层电梯控制系统设计》8900字
- 生产安全事故应急演练评估报告模版
- 退伍军人心理培训课件
- 2025年吉林铁道职业技术学院单招职业技能测试题库汇编
- “轻松前行压力不再”-高中生压力管理与情绪调节 课件-2024-2025学年高二下学期压力管理与情绪调节班会
- 开源社区治理模型-深度研究
评论
0/150
提交评论