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摘要
采用非原位掺杂方式,将化学气相沉积法生长的碳纳米管阵列在含氮和含硫的气氛下,700～900℃退火,制备了氮硫共掺杂的碳纳米管(NS-CNT)。X射线光电子能谱仪测试证明,通过非原位掺杂方式成功实现了氮和硫在碳纳米管上的掺杂。通过电化学测试研究退火温度对氧还原反应催化活性的影响,电化学测试结果表明,800℃退火所制备样品的氧还原峰电位和起始电位分别为0.873,0.771V,表现出最好的催化活性。通过旋转环盘电极测试发现,样品NS-CNT-800在反应过程中的反应电子数为3.7,说明该样品的反应机理是二电子和四电子反应同时进行,但以四电子反应过程为主,并研究了样品的长时间稳定性。与商业燃料电池所用的Pt/C催化剂相比,NS-CNT-800的稳定性更好,用于燃料电池有明显的优势。
Abstract
Nitrogen and sulfur co-doped vertically-aligned carbon nanotubes (N/S-CNT) were fabricated as an electrocatalyst for oxygen reduction reaction (ORR) by a two-step process involving preparation of vertically-aligned carbon nanotubes and subsequent annealing in a nitrogen and sulfur-containing atmosphere.The surface morphology,crystal structure and chemical composition of samples were investigated.Both cyclic voltammetry (CV) and rotating-disk electrode (RDE) measurements revealed that the annealing temperature had a significant impact on the ORR activity of catalyst in alkaline electrolyte.And the best ORR performance was achieved for the catalyst annealed at 800℃(N/S-CNT-800) in 0.1M KOH solution,which exhibited an onset potential of 0.873V and an ORR peak potential of 0.771V.Rotating ring-disk electrode (RRDE) testing in KOH showed an electron transfer number of around 3.7,indicating a four-electron pathway-dominated ORR process.And it had a significant advantage for long time stability over commercial Pt/C catalyst,making it an excellent substitute catalyst for PEMFC.
关键词
燃料电池
/
催化剂
/
氧还原反应
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起始电势
/
峰电势
Key words
fuel cell
/
electrocatalyst
/
oxygen reduction reaction
/
onset potential
/
peak potential
氮硫共掺杂碳纳米管的制备及其催化性能研究[J].
化工新型材料, 2018, 46(7): 127-130 DOI:
[1] Baker J L,Widmer-Cooper A,Toney M F,et al.What are batteries,fuel cells,and supercapacitors[J].Nano Letters,2010,10(1):195-201.
[2] 王林山,李瑛.燃料电池[M].北京:冶金工业出版社,2004.
[3] Lee K S,Jang C,Johnston C M,et al.The catalytic activities of sputtered cobalt metal electrocatalysts for polymer electrolyte membrane fuel cells[J].Solid State Ionics,2012,225:395-407.
[4] Wu M,Wang J,Z X,et al.Synergistic enhancement of nitrogen and sulfur co-doped graphene with carbon nanosphere insertion for the electrocatalytic oxygen reduction reaction[J].Mater Chem A,2015,3(15):7727-7731.
[5] Shi Qianqian,Peng F,Liao S X,et al.Sulfur and nitrogen co-doped carbon nanotubes for enhancing electrochemical oxygen reduction activity in acidic and alkaline media[J].Mater Chem A,2013(1):14853-14857.
[6] Roen L M,Paik C H,Jarvi T D.Electrocatalytic corrosion of carbon support in PEMFC cathodes[J].Electrochem Solid-State Lett,2004(7):19-24.
[7] Gong Kuanping,Du Feng,Durstoc M,et al.Nitrogen-doped carbon nanotube arrays with high electrocatalytic activity for oxygen reduction[J].Science,2009,323:760-763.
[8] Chao Shujun,Bai Zhengyu,Cui Qian,et al.Hollowed-out octahedral Co/N-codoped carbon as a highly efficient non-precious metal catalyst for oxygen reduction reaction[J].Carbon,2015,82:77-86.
基金资助
国家重大仪器开发专项(2012YQ15025602)
