Exfoliation of graphene via wet chemical routes

Abstract

a b s t r a c tGraphene is a two-dimensional material that has fascinating electrical and optical properties, and this material has provided chemists with great possibilities and challenges. Interests in graphene's exceptional physical and chemical properties and in its potential for applications have generated thousands of publications and have accelerated the pace of graphene research. Although considerable scientific progress has been achieved, the key to commercializing graphene lies in the cost-effective and scalable production of this material. Graphene can be produced using a variety of wet chemical methods, such as chemical oxidation followed by exfoliation, liquid-phase and electrochemical assisted exfoliation etc. from inexpensive and abundant sources such as graphite. This review article summarizes the recent progress toward the preparation of graphene through wet chemical routes and discusses their remaining challenges. In particular, the quality and yield of graphene sheets produced using these exfoliation protocols will be emphasized.

Evolution of the graphite surface in phosphoric acid: an AFM and Raman study

“…In particular, the evolution of blisters as a function of time has been analyzed in the past [9–10], supporting the theoretical model proposed by Murray [11]. H 3 PO 4 is another solvent that allows for successful graphite exfoliation, as reported quite recently [12–13]. However, a detailed analysis of the surface modification of a graphite crystal subjected to EC processes in phosphoric acid solution is still missing.…”

Graphen im Schulexperiment

“…Kaliumpermanganat oxidiert das Graphit zu Graphitoxid, welches durch UV‐Bestrahlung oder Ultraschallbehandlung zu Graphenoxid exfoliert wird. Bei der Reaktion entsteht jedoch Dimanganheptoxid Mn 2 O 7 , welches ab einer Temperatur von 55 °C zu explosiven Reaktionen neigt, sobald es mit organischen Komponenten in Berührung kommt . …”

Recent Advances in Effective Reduction of Graphene Oxide for Highly Improved Performance Toward Electrochemical Energy Storage

“…For the reduction process, chemical reducing agents are often used such as hydrazine and hydroiodic acid (HI), which are highly toxic. [39][40][41][42] Such chemically reduced products suffer from low carbon-to-oxygen ratio (C/O), [43] and the quality of the graphene sheets in these RGO powder is very poor compared to the graphene produced via mechanical/physical exfoliation or CVD. Additionally, reduction reaction employed in aqueous suspensions entails agglomeration of the RGO sheets.…”