Elsevier

Surfaces and Interfaces

Volume 21, December 2020, 100696
Surfaces and Interfaces

Fabrication of hollow carbon spheres doped with zinc cations to enhance corrosion protection of organosilane coatings

https://doi.org/10.1016/j.surfin.2020.100696Get rights and content

Abstract

Hollow carbon spheres (HCS) are spherical forms of carbon materials that can be used as nanocontainers due to their empty cores. In this work, zinc cations were doped in HCS (Zn@HCS) from an aquatic solution of zinc nitrate salt. Corrosion inhibition of released zinc cations in saline solution on bare mild steel samples was assessed by EIS, polarization, and electrochemical noise measurements. The sample surfaces were characterized through FTIR spectroscopy and grazing incidence XRD analyses after exposure to the test solutions. The results showed improvement in the corrosion resistance in the presence of Zn@HCS in a long immersion period. Zn@HCS were also incorporated in organosilane coating up to 5%. The EIS results showed a significant improvement in corrosion resistance of the samples at 2.5% wt. of Zn@HCS. FESEM and Raman mapping inspections of reinforced silane coatings approved morphological alteration of the coating surface in the form of severe heterogeneity and crack formation at 5% loading of Zn@HCS probably due to inappropriate nanocontainer dispersion.

Introduction

Reducing the cost of degradation and corrosion phenomena in most industrial applications always is a significant challenge for designers of corrosion protection systems. Many researches have been conducted to find new ways to improve the durability and stability of metal corrosion protection systems against corrosive media in long service times and ways for decreasing the toxicity and final cost of preparation and application of protective systems [1], [2], [3].

One of the most beneficial procedures for retarding the metal structures from damaging imposed by corrosion is the application of hybrid organic/inorganic silane coatings. These coatings, whether operated themselves or beneath the topcoats, have been deserved drastic considerations in industrial and academic sectors [4], [5], [6], [7]. High chemical, mechanical and thermal properties/stabilities, simple/fast application at ambient conditions, strong adhesion to metallic surfaces owning physicochemical bondings, and waste-free green processing are of the main reasons for gaining potent attention to these coatings [8], [9], [10], [11]. However, these coatings suffer micro- and nano-cracks propagation during either curing process or against harsh corrosive attacks, which remarkably restricts the anticipated long-time protective service [12,13].

One of the distinct approaches for reinforcing the performance of the conventional organosilane coatings is manipulating corrosion inhibitors into the silane matrix. Although many different types of materials are known as corrosion inhibitors for direct inclusion in the protective coatings, a new approach has been suggested in recent years for indirect use of inhibitors in coatings. The aim of using indirect inclusion is to avoid the unwanted consumption of inhibitors in the protective system, increasing the inhibition efficiency, conservation of protective coating's crosslinking density, and its barrier performance in longer service times [14,15]. The most interesting method for indirect use of inhibitors is to employ nano/micro-size container materials carrying inhibitors into corrosion protection systems. The presence of these containers could make a dual/active/barrier protective system to be more responsive and effective in the prevention of the structure's corrosion [16]. There are too many studies on the capabilities of different nano/micro compounds as potential carriers of organic/inorganic inhibitors through protective systems. The novel researches for controlling the storage capacity of containers, improving their responsive functions and stability factors, and trying new potential compounds is still going on [17], [18], [19], [20].

The containers could be selected from any intrinsically mesoporous and hollow material compounds or could have synthesized from organic/inorganic compounds in very desired morphologies and chemical properties [21], [22], [23]. Previously, mesoporous silica nanoparticles [24], [25], [26], ceria nanoparticles [27], [28], [29], zinc oxide nanoparticles [30] LDH (layered double hydroxide) pigments [31], [32], [33], montmorillonite [34,35], zeolite [36], [37], [38], [39], polyaniline [40], [41], [42], microorganism's shells [43], graphene oxide nano-platelets [44], halloysites [15,16,[45], [46], [47], [48], [49], [50], and hollow carbon spheres (HCS) [51,52] have been used as corrosion inhibitor containers.

The properties like tunable shell thickness, core size, and good mechanical strength lead to propel the attentions to HCS species as possible structures practically usable in oxygen reduction electrodes [53], hydrogen storages [54], supercapacitors [55], electrochemical Li-ion storages [56,57], fuel- and solar cells [58], polymeric coatings and inhibitor containers [51,59].

Zn2+ is one of the most interesting cations for mild steel in neutral saline solutions. This high interest could be originated from its ability to form a zinc hydroxide inhibitive film on the cathodic sites [60]. Applying modifications on the container's surfaces could be an effective procedure in controlled release mechanisms of inhibitors and could cause better compatibility between coating matrix and containers. Modifications can be conducted by adding further functionalities like amino groups [61] or adding additional layers on containers like polyelectrolyte layers deposition [50]. In the past, the loading of zinc cations as inorganic inhibitors in the containers such as halloysite [61], graphene oxide [62], micro/nano zeolite particles [36], sodium montmorillonite [63], and talc [64] has been investigated by this research team. Due to the good mechanical strength of the HCS, they can be easily dispersed in the coating matrix without rupture of the carbonic shell. To the best of our knowledge, no report is available about the loading of zinc cations in HCS for corrosion inhibition of mild steel in both corrosive solution and organic coating media. In this work, the Zn2+ cations were loaded into amine-functionalized hollow carbon spheres in order to fabricate an efficient nanocontainer-based inhibitor and investigating its barrier/inhibitive dual-functional effects in the organosilane coated steel for the first time. Moreover, the release behavior of the Zn2+ cations from the HCS nanoparticles at different pH conditions was evaluated. Besides, corrosion inhibition and characteristic features of the loaded particles on the bare and organosilane coated steel samples were investigated.

Section snippets

Materials

Mild steel substrates (ST37) were provided by Isfahan Foolad Mobarakeh corporation (Iran). Zinc nitrate was purchased from Merck Millipore company. Sodium chloride salt for preparing saline solution was supplied from Dr. Mojalali products. HCS nanocontainer has been received from the previous study [51]. The silane-based solution was prepared using tetraethyl orthosilicate (TEOS) and aminopropyl triethoxysilane (APTES), both obtained from Aldrich Co. (Germany). Acetic acid and ethanol were

Analysis of synthesized and loaded particles

Raman spectroscopy method was employed to study the loading of Zn2+ cations in the HCS. Graphene like G band, D band, and 2D peaks were detected in Fig. 1 for both HCS and Zn@HCS samples, which confirmed the graphene base structures of synthesized HCS. The G band peaks are related to the vibrational state of sp2 in-plane carbon atoms of graphene sheets. D band, commonly known as a defect or disorder band, appears because of ring breathing state of sp3 carbon atoms. The second D band, also named

Conclusions

Zn2+ cations have been successfully loaded to the hollow carbon spheres (HCS). Zn2+@HCS nanoparticles showed significant release in acidic and neutral pHs. Corrosion activity of steel substrates in the test electrolytes, assessed by EIS, polarization, and EN measurements exhibited significant improvement of the corrosion resistance in the presence of Zn2+ cations released from Zn@HCS particles. Released zinc cations effectively deposited as zinc hydroxide/oxide over the surface, forming an

Authors Contribution

M. Mahdavian and A. Ramazani conceived the idea. R. Behgam ran the experiments and wrote the first draft of manuscript. M. Mahdavian and A. Ramazani upervised the project. M. Mahdavian provided critical notes and prepared the final version of the manuscript.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References (77)

  • J.Q. Chi et al.

    Porous core-shell N-doped Mo2C@C nanospheres derived from inorganic-organic hybrid precursors for highly efficient hydrogen evolution

    J. Catal.

    (2018)
  • Y. Bao et al.

    Recent progress in hollow silica: template synthesis, morphologies and applications

    Microporous Mesoporous Mater.

    (2016)
  • R. Zandi Zand et al.

    Effects of ceria nanoparticle concentrations on the morphology and corrosion resistance of cerium–silane hybrid coatings on electro-galvanized steel substrates

    Mater. Chem. Phys.

    (2014)
  • M.F. Montemor et al.

    Chemical composition and corrosion protection of silane films modified with CeO2 nanoparticles

    Electrochim. Acta.

    (2009)
  • S.H. Sonawane et al.

    Improved active anticorrosion coatings using layer-by-layer assembled ZnO nanocontainers with benzotriazole

    Chem. Eng. J.

    (2012)
  • M.G. Hosseini et al.

    Effect of polyaniline-montmorillonite nanocomposite powders addition on corrosion performance of epoxy coatings on Al 5000

    Surf. Coatings Technol.

    (2011)
  • L. Rassouli et al.

    The role of micro/nano zeolites doped with zinc cations in the active protection of epoxy ester coating

    Appl. Surf. Sci.

    (2017)
  • A. Olad et al.

    Preparation, characterization and anticorrosive properties of a novel polyaniline/clinoptilolite nanocomposite

    Prog. Org. Coatings

    (2010)
  • N. Pirhady Tavandashti et al.

    Inhibitor-loaded conducting polymer capsules for active corrosion protection of coating defects

    Corros. Sci.

    (2016)
  • N. Asadi et al.

    Progress in Organic Coatings Synergistic e ff ect of imidazole dicarboxylic acid and Zn2+ simultaneously doped in halloysite nanotubes to improve protection of epoxy ester coating

    Prog. Org. Coatings

    (2019)
  • D. Yu et al.

    Preparation and controlled release behavior of halloysite/2- mercaptobenzothiazole nanocomposite with calcined halloysite as nanocontainer

    Mater. Des.

    (2017)
  • S.A. Haddadi et al.

    Fabrication and characterization of graphene-based carbon hollow spheres for encapsulation of organic corrosion inhibitors

    Chem. Eng. J

    (2018)
  • B. Zielinska et al.

    Pd supported ordered mesoporous hollow carbon spheres (OMHCS) for hydrogen storage

    Chem. Phys. Lett.

    (2016)
  • Z. Sanaei et al.

    Synthesis and characterization of an effective green corrosion inhibitive hybrid pigment based on zinc acetate-Cichorium intybus L leaves extract (ZnA-CIL. L): electrochemical investigations on the synergistic corrosion inhibition of mild steel in aqueous

    Dye. Pigment.

    (2017)
  • A. Bahrani et al.

    Chemical modification of talc with corrosion inhibitors to enhance the corrosion protective properties of epoxy-ester coating

    Prog. Org. Coatings

    (2018)
  • B. Hirschorn et al.

    Determination of effective capacitance and film thickness from constant-phase-element parameters

    Electrochim. Acta

    (2010)
  • A. Aballe et al.

    Wavelet transform-based analysis for electrochemical noise

    Electrochem. Commun.

    (1999)
  • S. Ramesh et al.

    Corrosion inhibition of mild steel in neutral aqueous solution by new triazole derivatives

    Electrochim. Acta.

    (2004)
  • S. Rajendran et al.

    Synergistic and antagonistic effects existing among polyacrylamide, phenyl phosphonate and Zn2+ on the inhibition of corrosion of mild steel in a neutral aqueous environment

    Electrochim. Acta.

    (1998)
  • S. Rajendran et al.

    Synergistic corrosion inhibition by the sodium dodecylsulphate-Zn2+ system

    Corros. Sci.

    (2002)
  • A.A. El-Meligi

    Corrosion Preventive Strategies as a Crucial Need for Decreasing Environmental Pollution and Saving Economics

    Recent Patents Corros. Sci.

    (2010)
  • E.A. Foroozan et al.

    Effect of coating composition on the anticorrosion performance of a silane sol-gel layer on mild steel

    RSC Adv.

    (2015)
  • M. Taheri et al.

    Development of an ecofriendly silane sol-gel coating with zinc acetylacetonate corrosion inhibitor for active protection of mild steel in sodium chloride solution

    J. Sol-Gel Sci. Technol.

    (2017)
  • R.B. Figueira et al.

    Organic–inorganic hybrid sol–gel coatings for metal corrosion protection: a review of recent progress

    J. Coatings Technol. Res.

    (2014)
  • S. Akbarzadeh et al.

    Fabrication of Highly Effective Polyaniline Grafted Carbon Nanotubes to Induce Active Protective Functioning in a Silane Coating

    Ind. Eng. Chem. Res.

    (2019)
  • S.V. Lamaka et al.

    Sol-gel/polyelectrolyte active corrosion protection system

    Adv. Funct. Mater.

    (2008)
  • E. Abdullayev, R. Price, D. Shchukin, Y. Lvov, Halloysite Tubes as Nanocontainers for Anticorrosion Coating with...
  • K. Azmi, Z. Universiti, T. Petronas, S. Kakooei, U. Teknologi, B. Raja, U. Sains, K.A. Zahidah, Benzimidazole-loaded...
  • Cited by (15)

    • Electrochemical noise energy generated by nickel electroplating process

      2023, Transactions of Nonferrous Metals Society of China (English Edition)
    • Detection of 2,4-dichlorophenoxyacetic acid in water sample by organosilane based silica nanocomposites

      2023, Science of the Total Environment
      Citation Excerpt :

      Because of its simplicity, cost-effectiveness and sensitivity, fluorescence-based technologies can have potential applications in the detection of trace quantities of this analyte (Wang et al., 2020; Bhamore et al., 2018). Organosilane has widespread applications in numerous fields such as synthetic organic chemistry, corrosion resistance, paints and coatings, hydrophobic agents and flame retardant (Srimani et al., 2010; Behgam et al., 2020; Witucki, 1993; Aydin and Sonmez, 2015; L. Zhang et al., 2020). 1,2,3-Triazoles are stimulating class of chemicals that can serve as effective linkers in molecular frameworks that are potentially active (Huo et al., 2017).

    View all citing articles on Scopus
    View full text