Elsevier

Sensors and Actuators B: Chemical

Volume 277, 20 December 2018, Pages 129-143
Sensors and Actuators B: Chemical

Growth of Eshelby twisted ZnO nanowires through nanoflakes & nanoflowers: A room temperature ammonia sensor

https://doi.org/10.1016/j.snb.2018.09.003Get rights and content

Highlights

  • Growth of screw dislocated Eshelby twisted ZnO nanowires.

  • Influence of precursor & deposition cycles in the growth of nanowires.

  • Transformation of nanoflakes to nanoflowers to twisted nanowires.

  • Twisted nanowires showed a response of 291 towards ammonia.

  • Response-recovery times of 39 and 17 s for 100 ppm of ammonia.

Abstract

Insight into the controlled growth features of nanowires has been in the prominent spotlight for engineering the material properties. Defect and dislocation induced nanowire growth has been emerging as a robust model by dwindling the conventional growth models. In this context, we have proposed a screw dislocated Eshelby twist origin in cationic assimilated ZnO nanowires synthesized via Successive Ionic Layer Absorption and Reaction (SILAR) technique. The growth of twisted nanowires occurred through a subsequent transformation from nanoflakes to nanoflowers. Presence of twist contours in various zone axis pattern provided strong validation of Eshelby origin in twisted nanowires. The preferential plane orientation of (0 0 0 2) confirmed the twisted growth along c-axis orientation. Presence of screw tail at the twisted end of nanowire confirmed the influence of Peach-Kohler force acted on the screw axis. Active vibrational modes and surface defect states of nanoflowers and nanowires were investigated and reported. Twisted ZnO nanowires showed maximum sensing response of 291 towards 100 ppm of ammonia at room temperature with the lowest detection limit of 5 ppm. The response and recovery times were found to be 39 and 17 s. Influence of grain alignment, grain orientation and potential barrier height on ammonia sensing signatures are reported.

Introduction

Design and development of nanoscale architectures create new pathways in the fabrication of sensors and devices with fascinating figure of merits [[1], [2], [3]]. Fabrication of two [4], one and zero-dimensional nanostructures offers properties like quantum confinement, quantum transport and enhanced surface to volume ratio. Among these nanostructures, one-dimensional nanowire/nanorods signify their importance in the fabrication of electrodes for batteries [5], touch screens, display devices [6], electrochromics [7], magnetic devices [8,9] flexible electronics [10], photo detector [11], gas sensor [1,12,13], photovoltaic cell [14], supercapacitor [15] and dye-sensitized solar cell [16]. In particular, the one-dimensional nanostructures of metal oxides namely TiO2 [17], Fe2O3 [18], SnO2 [19], ZnO [20], WO3 [21] have been synthesized and employed for various applications. In this group of widely exploited metal oxides, ZnO has been on the center of attraction over the past several decades due to its wide band gap, enhanced exciton binding energy, chemical stability, tunable transport characteristics and visible region transparency [22]. Among the 1D ZnO nanostructures, nanowire morphology has been preferred for the fabrication of chemical/gas sensors owing to its switching like transient response in the presence of target gas [23].

ZnO nanowires can be grown through popular mechanisms like vapor-liquid-solid (VLS), solution-liquid-solid (SLS) and vapor-solid-solid (VSS) [24]. However, these growth modes are highly relying on the need for metal nanoparticles as catalysts in the anisotropic growth. At the same time the growth of nanowires through axial screw dislocation mechanism [[24], [25], [26], [27]] does not require any metal catalyst for the unidirectional growth. Stephen et al. [27] have reported the epitaxial growth of ZnO nanowires in GaN substrate through screw dislocations and realizing the Eshelby twist. Bierman et al. [24] have synthesized screw dislocated pine tree like fashioned lead sulphide nanowires through CVD and observed the Eshelby twist. Zhu et al. [26] have demonstrated the formation of chiral lead selenide nanowires through combined VLS and screw dislocated mechanisms. Further, they have presented the growth mechanisms of chiral and branched nanowires through Eshelby twist. Senthil Kumar et al. [28] have reported the formation of ZnO nanowires, and hexagonal stacking from screw dislocations on a diamond substrate through nanoparticle assisted pulsed laser deposition technique. Also, the influence of growth velocity in the formation of these nanostructures were extensively reported [28]. In this context, SILAR technique has been preferred to grow ZnO nanowires adapting dislocation driven Eshelby twist growth model by controlling the deposition cycles. To observe the dislocation driven Eshelby twist phenomena, growth patterns of ZnO nanostructures synthesized using four different zinc precursors were considered. Based on the controlled growth features, ZnO nanostructures (nanoflowers to nanowires) synthesized using zinc sulphate precursor alone were taken in to account for the detailed investigation.

On the other hand, there is a massive demand for chemical sensors, which can work in the real-time ambient environment. The excessive presence of toxic gases or volatile organic compounds (VOCs) above the permissible human limits in the living environment result in adverse effects. One such lethal VOC is ammonia, and its presence in industries is familiar due to its significant production and usage [29]. According to Occupational Safety and Health Administration (OSHA), the short-term human permissible limits towards ammonia is 25–35 ppm as a weighted time average [30,29,31]. If this permissible limit exceeds in concentration or long-term exposure, it leads to the respiratory system impairment and even causes fatality [29]. As an impact of regular interactions with other air pollutants, it will also lead to sun blocking effects [32]. In this context, the present work highlights the use of ZnO nanowire to fabricate ammonia sensor with enhanced response characteristics.

Section snippets

Synthesis of ZnO nanowires

All the chemicals used for the synthesis were of analytical reagents and purchased from Merck, India. ZnO nanostructures were synthesized on the glass substrates using SILAR technique. Initially, glass substrates were sequentially ultrasonicated with diluted H2SO4, acetone, ethanol and deionized water. Cationic solutions were prepared by dissolving 0.1 M of four different zinc precursors namely zinc acetate ((Zn (CH3COO)2·2H2O, 98.5% purity), zinc chloride (ZnCl2, >98.5% purity), zinc nitrate

Structure and morphology

X-ray diffraction patterns of the SILAR grown nanostructures prepared using four different zinc precursors are shown in Fig. 2. These patterns revealed the formation of primitive hexagonal wurtzite phase of ZnO with polycrystalline nature. Diffraction peaks such as (1 0 1¯ 0), (0 0 0 2), (1 0 1¯ 1), (1 0 1¯ 2), (1 1 2¯ 0), (1 0 1¯ 3), (2 0 2¯ 0), (1 1 2¯ 2) and (2 0 2¯ 1) were observed for all the nanostructures deposited at both 50 and 100 deposition cycles. All the diffraction planes of ZA (1

Conclusion

A series of growth process involved in the formation of cationic assimilated twisted ZnO nanowires via SILAR deposition cycles have been highlighted. A conceptual framework for the growth transformation process from nanoflakes to nanoflowers and Eshelby twisted nanowires was formulated. Twisted tail in the nanowire confirmed the presence of screw dislocations and revealed the controlled dislocation growth features, which can be attained through engineering the cationic assimilation effect.

Acknowledgments

Authors wish to express their sincere thanks to the Department of Science & Technology, New Delhi, India for their financial support IDP/IND/2012/41 (General), ECR/2016/001805 and SR/FST/ETI-284/2011(C)). One of the author, Parthasarathy Srinivasan wish to expresses his sincere thanks to Council of Scientific and Industrial Research (HRDG- 09/1095/0016/2016-EMR-I) for the financial support. Authors thank Nano Mission, DST (SR/NM/PH-16/2007 and SR/NM/PH-04/2015) for their financial support. The

Parthasarathy Srinivasan received his M.Tech. degree in Nanoelectronics from SASTRA Deemed University, Thanjavur, India in the year 2015 and received his B.E. degree in Electronics and Communication Engineering from Arasu Engineering College, Kumbakonam, India, in the year 2013. He is currently working as a CSIR Senior Research Fellow and pursuing his Ph.D. in SASTRA Deemed University, Thanjavur, India. His current research includes development of Low dimensional metal oxide nanostructures as

References (83)

  • D. Sivasubramanian et al.

    Low power optical limiting and thermal lensing in Mn doped ZnO nanoparticles

    Mater. Chem. Phys.

    (2015)
  • F. Ren et al.

    Grain boundaries dependent hydrogen sensitivity in MAO-TiO2 thin films sensors

    Sens. Actuators B Chem.

    (2010)
  • N. Kakati et al.

    Thickness dependency of sol-gel derived ZnO thin films on gas sensing behaviors

    Thin Solid Films

    (2010)
  • G.K. Mani et al.

    A highly selective room temperature ammonia sensor using spray deposited zinc oxide thin film

    Sens. Actuators B Chem.

    (2013)
  • G.K. Mani et al.

    A highly selective and wide range ammonia sensor – nanostructured ZnO:Co thin film

    Mater. Sci. Eng. B Solid–State Mater. Adv. Technol.

    (2015)
  • G.K. Mani et al.

    Selective detection of ammonia using spray pyrolysis deposited pure and nickel doped ZnO thin films

    Appl. Surf. Sci.

    (2014)
  • R. Pandeeswari et al.

    High sensing response of β-Ga2O3 thin film towards ammonia vapours: influencing factors at room temperature

    Sens. Actuators B Chem.

    (2014)
  • H. Tai et al.

    Influence of polymerization temperature on NH3 response of PANI/TiO2 thin film gas sensor

    Sens. Actuators B Chem.

    (2008)
  • L. Schmidt-mende et al.

    ZnO-nanostructures,defects, and devices

    Mater. Today

    (2007)
  • G.K. Mani et al.

    Novel and facile synthesis of randomly interconnected ZnO nanoplatelets using spray pyrolysis and their room temperature sensing characteristics

    Sens. Actuators B Chem.

    (2014)
  • W.M. Sears

    The effect of oxygen stoichiometry on the humidity sensing characteristics of bismuth iron molybdate

    Sens. Actuators B Chem.

    (2000)
  • D. Sivalingam et al.

    Nanostructured ZnO thin film for hydrogen peroxide sensing

    Phys. E Low-Dimens. Syst. Nanostruct.

    (2011)
  • D. Sivalingam et al.

    Nanostructured mixed ZnO and CdO thin film for selective ethanol sensing

    Mater. Lett.

    (2012)
  • S. Lenaerts et al.

    FT-IR characterization of tin dioxide gas sensor materials under working conditions

    Spectrochim. Acta Part A Mol. Biomol. Spectrosc.

    (1995)
  • H. Li et al.

    Gas modulating effect in room temperature ammonia sensing

    Sens. Actuators B Chem.

    (2017)
  • M.S. Wagh et al.

    Modified zinc oxide thick film resistors as NH3 gas sensor

    Sens. Actuators B Chem.

    (2006)
  • G. Korotcenkov et al.

    Structural and gas response characterization of nano-size SnO2 films deposited by SILD method

    Sens. Actuators B Chem.

    (2003)
  • S.J. Chang et al.

    High sensitivity of a ZnO nanowire-based ammonia gas sensor with Pt nano-particles

    Nano Commun. Netw.

    (2010)
  • T. Wang et al.

    Studies on NH3 gas sensing by zinc oxide nanowire-reduced graphene oxide nanocomposites

    Sens. Actuators B Chem.

    (2017)
  • F. Shao et al.

    NH3 sensing with self-assembled ZnO-nanowire μHP sensors in isothermal and temperature-pulsed mode

    Sens. Actuators B Chem.

    (2016)
  • T.-Y. Chen et al.

    Characteristics of ZnO nanorods-based ammonia gas sensors with a cross-linked configuration

    Sens. Actuators B Chem.

    (2015)
  • B. Wang et al.

    Fabrication of a SnO2 nanowire gas sensor and sensor performance for hydrogen

    J. Phys. Chem. C

    (2008)
  • H.C. Chu et al.

    Spray-deposited large-area copper nanowire transparent conductive electrodes and their uses for touch screen applications

    ACS Appl. Mater. Interfaces

    (2016)
  • Y. Xu et al.

    PEG-assisted fabrication of single-crystalline Cul nanosheets: a general route to two-dimensional nanostructured materials

    J. Phys. Chem. C

    (2007)
  • M.-S. Park et al.

    Preparation and electrochemical properties of SnO2 nanowires for application in lithium-ion batteries

    Angew. Chem.

    (2007)
  • A.R. Madaria et al.

    Large scale, highly conductive and patterned transparent films of silver nanowires on arbitrary substrates and their application in touch screens

    Nanotechnology

    (2011)
  • C. Xiong et al.

    Fabrication of silver vanadium oxide and V2O5 nanowires for electrochromics

    ACS Nano

    (2008)
  • M.-H. Hung et al.

    Free-standing and single-crystalline Fe(1-x)Mn(x)Si nanowires with room-temperature ferromagnetism and excellent magnetic response

    ACS Nano

    (2012)
  • S. Zhang et al.

    Liquid crystalline order and magnetocrystalline anisotropy in magnetically doped semiconducting ZnO nanowires

    ACS Nano

    (2011)
  • D.A. Smith et al.

    Flexible germanium nanowires: ideal strength, room temperature plasticity, and bendable semiconductor fabric

    ACS Nano

    (2010)
  • E. Shalev et al.

    Guided CdSe nanowires parallelly integrated into fast visible-range photodetectors

    ACS Nano

    (2017)
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    Parthasarathy Srinivasan received his M.Tech. degree in Nanoelectronics from SASTRA Deemed University, Thanjavur, India in the year 2015 and received his B.E. degree in Electronics and Communication Engineering from Arasu Engineering College, Kumbakonam, India, in the year 2013. He is currently working as a CSIR Senior Research Fellow and pursuing his Ph.D. in SASTRA Deemed University, Thanjavur, India. His current research includes development of Low dimensional metal oxide nanostructures as gas/chemical sensors for food quality assessment

    John Bosco Balaguru Rayappan received his M.Sc. and Ph D. degrees in Physics from St. Joseph’s College, Bharathidasan University, Tiruchirapalli, India in 1996 and 2003, respectively. He is currently working as Associate Dean (Research) in the School of Electrical & Electronics Engineering and Centre for Nanotechnology & Advanced Biomaterials (CeNTAB) of SASTRA Deemed University, Thanjavur, India. His current research interests include development of gas/chemical sensors, biosensors for food & water quality and healthcare applications. He is also working in the field of embedded systems and steganography. He has published more than 220 research articles in peer reviewed international journals and filed six patents including a US patent.

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