Grafen Oksit Kabukların Boyutlarına Göre Sınıflandırılması: Deneysel Çalışma

Öz

Pratik uygulamalarda grafen kullanmak için grafen kabukların eşsiz ve münferit özelliklerinin makroskopik, düzenli malzemelere dönüştürülmesi çok önemlidir. Makro boyuttaki grafen yapıların fiziksel ve kimyasal özellikleri, bu yapıları oluşturan yapıtaşları olan grafen kabukların boyutları ile yakından ilgilidir. Bununla birlikte, kimyasal yöntemler kullanılarak üretilen grafen oksit (GO) kabuklarının boyutları istenilen aralıklarda kontrol edilememektedir. Bu çalışmanın amacı, farklı ortalama boyutlara sahip grafen kabuklar kullanılarak üretilen grafen esaslı fiberlerin morfolojik değerlendirmesini araştırmaktır. Grafen oksit kabukların boyut sıralanması için basit ve efektif bir santrifüj yöntemi uygulanmıştır. Makroskopik grafen oksit fiberleri, grafen oksit/su süspansiyonlarının sürekli olarak eğrilmesi ile üretilmiş bunu takiben indirgenmiş grafen oksit elyafı elde etmek için kimyasal ve termal indirgeme işlemleri yapılmıştır. Süspansiyon konsantrasyonu, enjeksiyon hızı ve orifis çapı gibi tüm ıslak eğirme parametreleri sabit tutularak, yanlızca grafen kabuk boyutunun fiberlerin yapısal morfolojisine etkisi araştırılmıştır. Mikroskopik incelemeler kabuk boyutunun, grafen oksit fiberlerin morfolojisi üzerinde çok büyük bir etkisi olduğunu ortaya koymuştur. Artan ortalama kabuk boyutu, grafen oksit fiberlerin kesitinin dikdörtgen geometrisine benzemesine ve fiber içerisindeki boşlukların artmasına neden olmuştur.

Anahtar Kelimeler

• Santrifüj,Kolloid,Boyut kontrolü,Grafen oksit,Görüntü işleme

INFLUENCE OF FLAKE SIZE ON THE MORPHOLOGY OF WET SPUN GRAPHENE OXIDE FIBERS

Abstract

For using graphene in practical applications, it is crucial to transform the unique and individual properties of graphene flakes into ordered macroscopic materials. The physical and chemical properties of macroscale graphene structures are closely related to the size of graphene flakes as building blocks. However, the chemical methods adopted to synthesize graphene oxide (GO) flakes offer no tight control on the dimensionality of the ensuring flakes sizes. The goal of this study is to investigate morphological evaluation of graphene based fibers fabricated using building blocks with different average size.. A facile and effective centrifugation method was carried out for size sorting of graphene oxide flakes. Macroscopic graphene oxide fibers were continuously spun from graphene oxide/water suspensions followed by chemical and thermal reductions to obtain reduced graphene oxide fibers. All wet spinning parameters such as suspension concentration, injection rate and nozzle diameter were fixed to investigate the effect of average building block size on the structural morphology of the fibers. Microscopic investigations revealed that the flake size have an enormous impact on the morphology of graphene oxide fibers. The increased average flake size results in the fibers with rectangular-like cross-section and increased amount of voids within the graphene oxide fiber.

Keywords

• Centrifugation,Colloid,Dimensional control,Graphene oxide,Image processing

Kaynakça

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