Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide chemical sensors.pdf
Скачиваний:
4
Добавлен:
13.02.2015
Размер:
1.12 Mб
Скачать

Home Search Collections Journals About Contact us My IOPscience

Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide

chemical sensors

This content has been downloaded from IOPscience. Please scroll down to see the full text. 2013 Nanotechnology 24 245502

(http://iopscience.iop.org/0957-4484/24/24/245502)

View the table of contents for this issue, or go to thejournal homepage for more

Download details:

IP Address: 91.198.212.14

This content was downloaded on 19/01/2014 at 14:01

Please note that terms and conditions apply.

IOP PUBLISHING

NANOTECHNOLOGY

Nanotechnology 24 (2013) 245502 (7pp)

doi:10.1088/0957-4484/24/24/245502

Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide chemical sensors

Christopher E Kehayias1, Samuel MacNaughton2, Sameer Sonkusale2

and Cristian Staii1

1 Department of Physics and Astronomy and Center for Nanoscopic Physics, Tufts University, 4 Colby Street, Medford, MA 02155, USA

2 NanoLab, Department of Electrical and Computer Engineering, Tufts University, 200 Boston Avenue, Medford, MA 02155, USA

E-mail: cristian.staii@tufts.edu

Received 18 March 2013, in final form 7 May 2013

Published 23 May 2013

Online at stacks.iop.org/Nano/24/245502

Abstract

Reduced graphene oxide (RGO) is an electronically hybrid material that displays remarkable chemical sensing properties. Here, we present a quantitative analysis of the chemical gating effects in RGO-basedchemical sensors. The gas sensing devices are patterned in afield-effecttransistor geometry, by dielectrophoretic assembly of RGO platelets between gold electrodes deposited on SiO2/Si substrates. We show that these sensors display highly selective and reversible responses to the measured analytes, as well as fast response and recovery times (tens of seconds). We use combined electronic transport/Kelvin probe microscopy measurements to quantify the amount of charge transferred to RGO due to chemical doping when the device is exposed toelectron-acceptor(acetone) andelectron-donor(ammonia) analytes. We demonstrate that this method allows us to obtainhigh-resolutionmaps of the surface potential and local charge distribution both before and after chemical doping, to identify localgate-susceptibleareas on the RGO surface, and to directly extract the contact resistance between the RGO and the metallic electrodes. The method presented is general, suggesting that these results have important implications for building graphene and othernanomaterial-basedchemical sensors.

S Online supplementary data available fromstacks.iop.org/Nano/24/245502/mmedia

(Some figures may appear in colour only in the online journal)

1. Introduction

Graphene and its chemical derivatives are proving to be very promising candidates for applications in a variety of fields, such as nanoscale electronics [14],mechanical engineering [5,6], chemical sensing[710],and biosensing[1114].Graphene has a characteristictwo-dimensional

Content from this work may be used under the terms oftheCreative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the

title of the work, journal citation and DOI.

honeycomb lattice structure [2], which makes the electronic transport of charge carriers in this material extremely sensitive to adsorption/desorption of gas molecules. Both bare and chemically functionalizedgraphene-basedelectronic devices are reported to be sensitive to various gases down to very low concentrations[69,1517],thus endorsing the use ofgraphene-relatedmaterials as nanoscale chemical vapor sensors.

Reduced graphene oxide (RGO) platelets constitute a very promising, cost-effectivechoice for building graphenebased electronic sensors [6,9,10,15,16,18]. RGO is

0957-4484/13/245502C07$33.00

1

c 2013 IOP Publishing Ltd Printed in the UK & the USA

Калькулятор

Сервис бесплатной оценки стоимости работы

  1. Заполните заявку. Специалисты рассчитают стоимость вашей работы
  2. Расчет стоимости придет на почту и по СМС

Нажимая на кнопку, вы соглашаетесь с политикой конфиденциальности и на обработку персональных данных.

Номер вашей заявки

Прямо сейчас на почту придет автоматическое письмо-подтверждение с информацией о заявке.

Оформить еще одну заявку