Sonikasyon işleminin grafen oksit yapısal özellikleri üzerindeki etkisinin değerlendirilmesi

Year 2024, Volume: 13 Issue: 4, 1139 - 1149, 15.10.2024

Fatih Sargın , Funda Ak Azem , Kürşat Kanbur , Işıl Birlik , Ahmet Türk

https://doi.org/10.28948/ngumuh.1470478

Abstract

Karbon bazlı nanomalzemelerin üyelerinden biri olan grafen oksit (GO), basitçe çeşitli oksijen içerikli fonksiyonel gruplarca dekore edilmiş grafen yapısı olarak da tanımlanabilmektedir. Hummers yöntemi, uygulama kolaylığı, parametre kontrol edilebilirliği ve yüksek verimi nedeniyle GO nanomalzemelerinin üretimi için en sık kullanılan, çok yönlü yöntemlerden biridir. Bu yöntem, başlangıç malzemesi olan grafitin oksidasyonunu ve tek veya birkaç katmanlı GO tabakaları şeklinde katmanlara ayrılmasına imkân vermektedir. Eksfoliasyon, çok katmanlı grafit oksit tabakalarının veya parçacıklarının birbirinden ayrılması, oksitleyici ajanların veya solvent moleküllerinin bu katmanlar arasına girmesi sürecidir. Sonikasyon işlemi ise oksitlenmiş katmanları birbirinden ayırarak yalnızca bir veya birkaç karbon atomundan meydana gelen tek katmanlı GO yapısının oluşmasını sağlamaktadır. Bu proses GO bazlı nanomalzemelerin özelliklerini etkileyen Hummers yönteminin temel parametreleri arasında yer almaktadır. Bu çalışmada sonikasyon işlem süresi ve güç parametrelerinin GO nanomalzemlerin morfolojik ve yapısal özelliklerine etkisi incelenmiştir. Bu amaçla taramalı elektron mikroskobu (SEM), X-ışını kırınımı (XRD), Fourier-transform kızılötesi spektroskopisi (FTIR), UV-Vis spektroskopisi ve Raman spektroskopisi analizi kullanılarak karakterizasyon çalışmaları yapılmıştır. Uygulanan sonikasyon gücü ve süresindeki artışın katmanlar arası mesafenin azalmasına ve elde edilen GO yapısında kusurların artmasına neden olduğu tespit edilmiştir. Bulgular, en düşük güç ve en kısa sonikasyon süresine tabii tutulan numunenin, 7,83Å ile en yüksek katmanlar arası mesafe değerine ve 1,62 ile en düşük C/O oranına sahip olduğunu ortaya çıkardı. Sonuç olarak, diğer numunelerle kıyasla en yüksek oksidasyon seviyesini sergilemiştir.

Keywords

grafen oksit, eksfoliasyon, sonikasyon

Project Number

Project number: 2020-038

Evaluating the impact of sonication process on graphene oxide structural properties

Abstract

Graphene oxide (GO) is one of the members of carbon-based nanomaterials and can be featured as a graphene structure decorated with various oxygenated functional groups. Hummers method is one of the most known and versatile methods for the production of GO nanomaterials because of its ease of application, parameter controllability, and high yield. This process enables graphite oxidation and exfoliation into single or multi-layered GO sheets. Exfoliation separates multilayered graphite oxide flakes or particles; it forms single layer GO by forcing oxidizing agents or solvent molecules between layers. The sonication process can exfoliate the oxidized layers, resulting in the formation of GO structure when the exfoliated layers consist of only one or a few layers of carbon atoms. This process is considered among the key parameters of the Hummers method that influence the characteristics of GO-based nanomaterials. In this study, the impact of sonication process parameters, duration time, and power on morphological and structural characteristics of GO development was examined. For this purpose, characterization studies were performed by using a Scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and Raman spectroscopy analysis. It has been determined that the increase in applied sonication power and duration causes the distance between layers to decrease and defects to increase in the resulting GO structure. The findings revealed that the sample treated with the lowest power and shortest sonication time had the highest interlayer distance value of 7.83Å and the lowest C/O ratio of 1.62. Consequently, it exhibited the highest oxidation level compared to the other samples.

Keywords

graphene oxide, exfoliation, sonication

Supporting Institution

Manisa Celal Bayar University Scientific Research Projects Coordination Unit (Project number: 2020-038)

Project Number

Project number: 2020-038

Thanks

The authors would like to thank the Manisa Celal Bayar University Scientific Research Projects Coordination Unit (Project number: 2020-038) for their financial support of this study. The authors express special thanks to Dokuz Eylul University (DEU) Department of Metallurgical and Materials Engineering and Center for Fabrication and Application of Electronic Materials for their valuable assistance.

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