4 3 6 Vol 43 No 6 2 0 1 4 1 2 Journal of Shanghai Normal University Natural Sciences Dec 2 0 1 4 DOI 10 3969 /J ISSN 1000-5137 2014 06 008 PdNPs / MWNTs 200234 用 钯 纳 米 粒 子 多 壁 碳 纳 米 管 修 饰 玻 碳 电 极, 并 用 于 对 六 价 铬 ( Cr( VI) ) 的 电 化 学 测 定 采 用 场 发 射 扫 描 电 子 显 微 镜 循 环 伏 安 法 交 流 阻 抗 法 差 分 脉 冲 伏 安 法 等 方 法 对 修 饰 电 极 进 行 了 表 征 研 究 发 现 多 种 其 他 金 属 离 子 如 Cr 3 + Pd 2 + Zn 2 + Pb 2 + Cu 2 + Al 3 + Ba 2 + Ca 2 + Mg 2 + 等 对 六 价 铬 离 子 的 测 定 没 有 明 显 干 扰, 且 六 价 铬 的 还 原 峰 电 流 与 Cr( VI) 的 浓 度 在 8 10-7 ~ 5 10-8 mol /L 范 围 内 呈 良 好 线 性 关 系, 检 测 限 达 2 7 10-8 mol /L 该 法 具 有 简 便 快 速, 选 择 性 好, 灵 敏 度 高 等 特 点 六 价 铬 Cr( VI) ; 钯 纳 米 粒 子 ; 多 壁 碳 纳 米 管 ; 电 化 学 ; 修 饰 电 极 O 657 1 0 A 1000-5137 2014 06-0594-06 1-3 4-6 7 8 9 10 11 Cr VI 12-13 Cr 14 - VI 15 2014-12-03 DXL123 100 200234 E-mail zhunn@ shnu edu cn
6 PdNPs /MWNTs 595 Cr VI 1 1 1 CHI-660B SCE PS-20A JBZ- 12H Veeco Nano III a Multimode S-4800 FE-SEM Hitachi phs-3c ph 1 2 MWNTs 40 ~ 60 nm N-N DMF PBS ph = 7 0 0 1 10 6 mol L - 1 0 1 10 6 mol L - 1 1 0 10 3 mol L - 1 0 1 10 6 mol L - 1 1 0 10 3 mol L - 1 / 1 1 0 1 10 6 mol L - 1 Milli-Q 18 2 MΩ 1 3 1 GCE 0 3 μm 0 05 μm Al 2 O 3 8 3 min Al 2 O 3 1 mg MWNTs 1 ml N-N DMF 2 h 1 mg /ml 5 μl MWNTs MWNTs /GCE MWNTs /GCE 2 5 10 3 mol L - 1 PdCl 2 + 0 1 10 6 mol L - 1 KCl - 0 2V 100 s PdNPs / MWNTs /GCE 1 1 4 Cr VI CV GCE MWNTs /GCE PdNPs / MWNTs /GCE 0 5 10 3 mol L - 1 Cr VI - 1 0 ~ 1 0 V 100 mv s - 1 EIS 1 0 10 3 mol L - 1 K 3 Fe CN 6 /K 4 Fe CN 6 1 1 0 1 10 6 mol L - 1 KCl DPV 5 10-2 mol L - 1 ~ 8 10-1 mol L - 1 Cr VI 2 2 1 2 1 1 FE-SEM PdNPs /MWNTs FE-SEM 2 2
596 2014 PdNPs /MWNTs 2 20 ~ 40 nm PdNPs MWNTs 2 PdNPs /MWNTs /GCE FE-SEM 2 1 2 CV 3 a GCE b MWNT /GCE c PdNPs-MWNT /GCE 1 0 10 3 mol L - 1 3c PdNPs-MWNT 4 a GCE b MWNT / GCE c PdNPs /MWNT /GCE / 4 a b PdNPs 4c PdNPs 3 a GCE b MWNTs /GCE c PdNPs /MWNTs /GCE 4 a GCE b MWNTs /GCE c PdNPs /MWNTs /GCE 2 2 1 10 3 mol L - 1 K3Fe CN 6 1 10 3 mol L - 1 Fe CN 6 4 - /3-0 1 10 6 mol L - 1 KCl 5 a GCE b MWNTs /GCE d PdNPs /MWNTs /GCE 5 10 2 mol L - 1 Cr VI 0 1 10 6 mol L - 1 PBS ph 7 0 5 a b MWNTs /GCE - 0 7V vs SCE Cr VI d PdNPs /MWNTs /GCE- 0 7V vs SCE Cr VI
6 PdNPs /MWNTs 597 PdNP S Cr VI - 0 6V Cr VI c PdNPs /MWNTs /GCE Cr VI 0 1 10 6 mol L - 1 PBS ph 7 0-0 7V vs SCE d - 0 7V Cr VI PdNPs /MWNTs /GCE Cr VI 2 3 ph ph 6 PdNPs /MWNTs /GCE ph 4 0 5 0 6 0 7 0 8 0 9 0 0 1 10 6 mol L - 1 PBS 5 10 2 mol L - 1 Cr VI ph 7 0 ph 7 0 9 0 6 ph 7 0 ph 7 0 a GCE b MWNTs /GCE c Pd NPs /MWNTs /GCE without Cr VI d PdNPs / MWNTs /GCE 0 1 10 6 mol L - 1 PBS 5 ph 7 0 100 mv s - 1 0 5 10 3 mol L - 1 Cr VI 6 0 1 10 6 mol L - 1 ph 4 0 ~ 9 0 Cr VI 2 4 7 PdNPs /MWNTs / GCE 0 5 10 3 mol L - 1 Cr VI 0 1 10 6 mol L - 1 PBS ph = 7 0 7 20 ~ 200 mv s - 1 Cr VI 20 ~ 100 mv s - 1 Ip μa = - 5 103υ 1 /2 mv s - 1 + 15 35 R = 0 9980 2 5 7 PdNPs /MWNTs /GCE a ~ f 20 40 60 80 100 200 mv s - 1 0 5 10 3 mol L - 1 Cr VI Cr VI 8A Pd NPs /MWNTs /GCE 1 10 5 mol L - 1 PBS ph = 7 0
598 2014 5 10 2 ~ 8 10-1 mol L - 1 Cr VI 8 b ~ f - 0 73V a PBS 8A Cr VI 8B 5 10-2 ~ 8 10-1 mol L - 1 I = - 15 58c - 3 674 R = 0 9960 2 7 10-2 mol L - 1 S /N = 3 8 0 1 10 6 mol L - 1 PBS ph 7 0 a blank b 5 10-2 mol L - 1 c 1 10-1 mol L - 1 d 2 10-1 mol L - 1 e 5 10-1 mol L - 1 f 8 10-1 mol L - 1 A Pd NPs /MWNTs /GCE Cr VI B ph 7 0 0 1 10 6 mol L - 1 PBS 1 10-1 mol L - 1 Cr VI Zn 2 + Pb 2 + Cu 2 + Cr 3 + Al 3 + Ba 2 + Ca 2 + Mg 2 + Cr VI 50 3 1 PEREZ A C RENEDO O D LOMILLO M A A et al Simultaneous determination of Cr III and Cr VI by differential pulse voltammetry using modified screen-printed carbon electrodes in array mode J Electroanalysis 2010 22 24 2924-2930 2 ANDRLE C M BROEKAERT J A C Speciation of Cr III and Cr VI by reversed phase high-performance liquid chromatography using UV-detection J Fresenius J Anal Chem 1993 346 653-658 3 POSTA J GASPAR A TOTH R et al Cr III and Cr VI on-line preconcentration and determination with high performance flow flame emission spectrometry in natural samples J Fresenius J Anal Chem 1996 355 719-720 4 ZAZOUA A MORAKCHI K KHERRAT R et al Electrochemical characterization of an EIS sensor functionalized with a TOPO doped polymeric layer for Cr VI detection J ITBM-RBM 2008 29 187-191
6 PdNPs /MWNTs 599 5 CHOI Y W MOON S H Determination of Cr VI using a pulse amperometric method with an ionophore-immobilized membrane electrode J Electroanalysis 2004 16 11 932-937 6 GUELL R FONTAS C SALVADO V et al Development of a selective optical sensor for Cr VI monitoring in polluted waters J Analytica Chimica Acta 2007 594 162-168 7 MILACIC R SCANCAR J TUSEK J Determination of Cr VI in welding fumes by anion-exchange fast protein liquid chromatography with electrothermal atomic absorption spectrometric detection J Anal Bioanal Chem 2002 372 549-553 8 GRATE J W TAYLOR R H Sequential injection method with on-line soil extraction for determination of Cr VI J Field Analytical Chemistry And Technology 1996 1 1 39-48 9 WELCH C M NEKRASSOVA O COMPTON R G Reduction of hexavalent chromium at solid electrodes in acidic media reaction mechanism and analytical applications J Talanta 2005 65 74-80 10 RAJ C R ABDELRAHMAN A I OHSAKA T Gold nanoparticle-assisted electroreduction of oxygen J Electrochem Commun 2005 7 888-893 11 LIU S Q JU H X Nitrite reduction and detection at a carbon paste electrode containing hemoglobin and colloidal gold J Analyst 2003 128 1420-1424 12 LIU B Z LU L Y WANG M et al A study of nanostructured gold modified glassy carbon electrode for the determination of trace Cr VI J J Chem Sci 2008 120 5 493-498 13 XU H ZHENG Q L YANG P et al Electrochemical synthesis of silver nanoparticles-coated gold nanoporous film electrode and its application to amperometric detection for trace Cr VI J Sci China Chem 2011 54 6 1004-1010 14 ZHENG Z X DU Y L FENG Q L et al Facile method to prepare Pd / graphene-polyaniline nanocomposite and used as new electrode material for electrochemical sensing J Journal of Molecular Catalysis A Chemical 2012 353-354 80-86 15 YOU J M JEON S Electrocatalytic oxidation of NADH on a glassy carbon electrode modified with MWCNT-Pd nanoparticles and poly 3 4-ethylenedioxypyrrole J Electrochimica Acta 2011 56 10077-10082 Preparation of palladium nanoparticles and carboxylated MWNTs modified glassy carbon electrode and its application for the electrochemical determination of Cr VI YANG Shuai TANG Wanxin ZHANG Chao ZHU Ningning College of Life and Environmental Sciences Shanghai Normal University Shanghai 200234 China Abstract This study described a simple and rapid method for the electrochemical determination of Cr VI based on palladium nanoparticles and carboxylated multi-walled carbon nanotubes MWNTs modified glassy carbon electrode GCE written as PdNPs-MWNT /GCE The prepared PdNPs-MWNT /GCE was characterized by FE-SEM CV EIS and DPV It was found that many other metal ions such as Cr 3 + Pd 2 + Zn 2 + Pb 2 + Cu 2 + Al 3 + Ba 2 + Ca 2 + Mg 2 + had no influence on Cr VI determination Under the optimal conditions the reduction current of Cr VI increased linearly with increasing the concentration of Cr VI in the range of 8 10-7 ~ 5 10-8 mol /L with a correlation coefficient of 0 9960 and the detection limit of 3 10-8 mol /L based on S /N = 3 The present method has the following advantages such as simple rapid good selectivity and sensitivity Key words Cr VI PdNPs MWNTs electrochemical modified electrode ( 责 任 编 辑 : 顾 浩 然 )