• 文献标题:   Fast pulsed amperometric waveform for miniaturised flow-through electrochemical detection: Application in monitoring graphene oxide reduction
  • 文献类型:   Article
  • 作  者:   ISLAM MA, KORESHKOVA AN, GUPTA V, LEWIS T, MACKA M, PAULL B, MAHBUB P
  • 作者关键词:   pulsed amperometric detection fast waveform, miniaturised flowbased electrochemical detection, hydrazine ascorbic acid, graphene oxide reduction
  • 出版物名称:   ELECTROCHIMICA ACTA
  • ISSN:   0013-4686 EI 1873-3859
  • 通讯作者地址:   Univ Tasmania
  • 被引频次:   0
  • DOI:   10.1016/j.electacta.2019.135087
  • 出版年:   2019

▎ 摘  要

A fast pulsed waveform (2-steps at +400 mV and -400 mV, 10 ms each, 50 Hz cycle repetition) was developed incorporated within a miniaturised EC detector, and used to demonstrate the pulsed amperometric detection (PAD) of hydrazine in a flow-based analytical system. In contrast to standard amperometric detection (AD), a subsequent surface oxide reduction step was applied within the PAD waveform. The PAD applied within a simple flow-injection analysis (FIA) method provided a limit of detection (LOD) just as low as 0.8 nM of hydrazine (RSD 5%, n = 9, linearity r(2) = 0.99 for 1 nM-100 mM), which is one order of magnitude lower than the lowest LOD reported todate. Significantly, the LOD was obtained using 5-20 times lower electrode surface area, flow rate, and sample volume, than in previous methods, with 15 times faster cycle repetition frequency than alternative PAD based studies reported in literature. Practical application of the PAD waveform was demonstrated by monitoring the temporal consumption of reducing agents during graphene oxide reduction experiments, separated using chromatographic methods (hydrazine in IC and ascorbic acid in HPLC). (C) 2019 Elsevier Ltd. All rights reserved.