An on-chip electrical transport spectroscopy approach for in situ monitoring electrochemical interfaces.

Gongming Wang,Mengning Ding,Hung-Chieh Cheng,Qiyuan He,Yu Huang,Xiangfeng Duan

doi:10.1038/ncomms8867

Gongming Wang, Mengning Ding + Show 4 more

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https://doi.org/10.1038/ncomms8867

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Abstract

In situ monitoring electrochemical interfaces is crucial for fundamental understanding and continued optimization of electrocatalysts. Conventional spectroscopic techniques are generally difficult to implement for in situ electrochemical studies. Here we report an on-chip electrical transport spectroscopy approach for directly probing the electrochemical surfaces of metallic nanocatalysts in action. With a four-electrode device configuration, we demonstrate that the electrical properties of ultrafine platinum nanowires are highly sensitive and selective to the electrochemical surface states, enabling a nanoelectronic signalling pathway that reveals electrochemical interface information during in-device cyclic voltammetry. Our results not only show a high degree of consistency with generally accepted conclusions in platinum electrochemistry but also offer important insights on various practically important electrochemical reactions. This study defines a nanoelectronic strategy for in situ electrochemical surface studies with high surface sensitivity and surface specificity.

Highlights

In situ monitoring electrochemical interfaces is crucial for fundamental understanding and continued optimization of electrocatalysts
In situ electrochemical surface study is most informative[9], yet extremely challenging because these interfaces are generally buried between solid support and liquid electrolyte and are difficult to access by the conventional spectroscopic techniques
With a properly designed nanodevice based on the network of ultrafine platinum nanowires (PtNWs), in-device cyclic voltammetry (CV) of PtNWs is performed with concurrent in situ measurement of their electrical conductivity

Summary

Introduction

In situ monitoring electrochemical interfaces is crucial for fundamental understanding and continued optimization of electrocatalysts. With a properly designed nanodevice based on the network of ultrafine platinum nanowires (PtNWs), in-device cyclic voltammetry (CV) of PtNWs is performed with concurrent in situ measurement of their electrical conductivity This method allows us to use the nanoelectronic device as an electronic probe, alternative to the spectroscopic probes, for in situ monitoring the dynamic electrochemical interface characteristics between the metallic nanostructures and electrolyte under variable electrochemical conditions. A systematic analysis of the electrical signals of PtNWs shows a high degree of consistency with the generally accepted conclusions in the field of Pt electrochemistry It reveals important new insights on various Pt-catalysed electrochemical reactions

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Results

Conclusion