Reduced Graphene Oxide Films as Solid Transducers in Potentiometric All-Solid-State Ion-Selective Electrodes

Rafael Hernández, Jordi Riu, Johan Bobacka, Cristina Vallés, Pablo Jiménez, Ana M. Benito, Wolfgang K. Maser, F. Xavier Rius

Research output: Contribution to journalArticleScientificpeer-review

76 Citations (Scopus)

Abstract

The development of ion-selective electrodes (ISEs) using solid-state transducer materials is of great interest for advanced potentiometric detection systems. At present, conducting polymers are the most used solid-state transducing materials. However, their reliability is strongly related to their chemical stability and the formation of internal water films. Here we report on the use of reduced graphene oxide (RGO) films of different thicknesses as transducer materials in potentiometric all ISEs. First, the transduction mechanism is fully analyzed, revealing that RGO films act as asymmetric capacitors where their electron density is in contact with ions of the electrolyte solution, creating a capacitance due to the constant phase elements present in the system. Second, as a proof of concept, RGO films are used in a calcium ISE showing highly reproducible sensing responses and outstanding increased signal-to-noise ratios with drifts of only 10 mu V/h. These performance parameters are among the best compared to those of other ISE transducer materials so far. With its ease of fabrication and processing into reproducible films of controlled thickness and ease for further tailoring chemical composition and tailoring electrical properties, RGO offers great promise as a reliable high-performance transducer material for solid-state ISE sensors.
Original languageUndefined/Unknown
Pages (from-to)22570–22578
Number of pages9
JournalJournal of Physical Chemistry C
Volume116
Issue number42
DOIs
Publication statusPublished - 2012
MoE publication typeA1 Journal article-refereed

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