We present an overview of the main techniques for production and processing of graphene and related materials (GRMs), as well as the key characterization procedures. We adopt a ‘hands-on’ approach, providing practical details and procedures as derived from literature as well as from the authors’ experience, in order to enable the reader to reproduce the results. Section is devoted to ‘bottom up’ approaches, whereby individual constituents are pieced together into more complex structures. We consider graphene nanoribbons (GNRs) produced either by solution processing or by on-surface synthesis in ultra high vacuum (UHV), as well carbon nanomembranes (CNM). Production of a variety of GNRs with tailored band gaps and edge shapes is now possible. CNMs can be tuned in terms of porosity, crystallinity and electronic behaviour. Section covers ‘top down’ techniques. These rely on breaking down of a layered precursor, in the graphene case usually natural crystals like graphite or artificially synthesized materials, such as highly oriented pyrolythic graphite, monolayers or few layers (FL) flakes. The main focus of this section is on various exfoliation techniques in a liquid media, either intercalation or liquid phase exfoliation (LPE). The choice of precursor, exfoliation method, medium as well as the control of parameters such as time or temperature are crucial. A definite choice of parameters and conditions yields a particular material with specific properties that makes it more suitable for a targeted application. We cover protocols for the graphitic precursors to graphene oxide (GO). This is an important material for a range of applications in biomedicine, energy storage, nanocomposites, etc. Hummers’ and modified Hummers’ methods are used to make GO that subsequently can be reduced to obtain reduced graphene oxide (RGO) with a variety of strategies. GO flakes are also employed to prepare three-dimensional (3d) low density structures, such as sponges, foams, hydro- or aerogels. The assembly of flakes into 3d structures can provide improved mechanical properties. Aerogels with a highly open structure, with interconnected hierarchical pores, can enhance the accessibility to the whole surface area, as relevant for a number of applications, such as energy storage. The main recipes to yield graphite intercalation compounds (GICs) are also discussed. GICs are suitable precursors for covalent functionalization of graphene, but can also be used for the synthesis of uncharged graphene in solution. Degradation of the molecules intercalated in GICs can be triggered by high temperature treatment or microwave irradiation, creating a gas pressure surge in graphite and exfoliation. Electrochemical exfoliation by applying a voltage in an electrolyte to a graphite electrode can be tuned by varying precursors, electrolytes and potential. Graphite electrodes can be either negatively or positively intercalated to obtain GICs that are subsequently exfoliated. We also discuss the materials that can be amenable to exfoliation, by ...

The formation of discrete macrocycles wrapped around single-walled carbon nanotubes (SWCNTs) has recently emerged as an appealing strategy to functionalize these carbon nanomaterials and modify their properties.H ere,w e demonstrate that the reversible disulfide exchange reaction, which proceeds under mild conditions,c an install relatively large amounts of mechanically interlocked disulfide macrocycles on the one-dimensional nanotubes.S ize-selective functionalization of am ixture of SWCNTs of different diameters were observed, presumably arising from error correction and the presence of relatively rigid, curved p-systems in the key building blocks.Acombination of UV/Vis/NIR, Raman, photoluminescence excitation, and transient absorption spectroscopyindicated that the small (6,4)-SWCNTs were predominantly functionalizedbythe small macrocycles 1 2 ,whereas the larger (6,5)-SWCNTs were an ideal matchf or the larger macrocycles 2 2 .T his sizes electivity,w hich was rationalized computationally,c ould prove useful for the purification of nanotube mixtures,s ince the disulfide macrocycles can be removed quantitatively under mild reductive conditions.

No abstract

Controlled covalent functionalization of graphene remains a challenging task owing to the heterogeneous nature of materials. Functionalization approaches for graphene either lack in quantifying the degree of functionalization or they do not discriminate between covalent and non-covalent functionalization. Here, graphite is oxidized and exfoliated in a three-step procedure and subsequently reduced and functionalized by hexylation. Although Raman spectroscopy is powerful to determine the degree of in-plane lattice defects (θ ) and functionalization (θ ), the method fails at detecting introduced hexyl groups at a concentration of about 0.03 %, next to the pre-existing in-plane lattice defects of 0.7 %. However, sensitive thermogravimetric analysis coupled with gas chromatography and mass spectrometry (TGA-GC/MS) can prove the hexylation reaction. The efficiency of functionalization is comparable to reductive functionalization of pristine chemical vapor deposition (CVD)-graphene and bulk graphite.

Using a reductive sidewall functionalization concept, we prepared for the first time a covalent inter‐carbon‐allotrope hybrid consisting of single‐walled carbon nanotubes (SWCNTs) and the endohedral fullerene Sc3N@C80. The new compound type was characterized through a variety of techniques including absorption spectroscopy, Raman spectroscopy, TG‐MS, TG‐GC‐MS, and MALDI‐TOF MS. HRTEM investigations were carried out to visualize this highly integrated architecture.

Tw on ovel graphene-fullerene hybrid structures, containing C 60 and endohedral Sc 3 N@C 80 bound to graphene, instead of the formerly used graphene oxide,w ere efficiently synthesized via ar eductive activation/exfoliation approach starting from pristine graphite.T he structures of these multifunctional hybrid systems were unambiguously characterized by statistical Raman spectroscopy, TG-MS,T G-GC-MS,a nd LD-TOF mass spectroscopy, confirming the covalent bonding of the respective C 60 /Sc 3 N@C 80 moieties to the pristine graphene.F urthermore,a ssisted by temperature-dependent Raman spectroscopys tudies the corresponding defunctionalization processes were also investigated. Finally,the formation of ac arbon allotrope hybrid material on the basis of C 60 /Sc 3 N@C 80 moieties coupled to graphene could be visualized by HRTEM.

Die Bildung von diskreten Makrozyklen, die sich um einwandige Kohlenstoffnanorçhren (SWCNTs) bilden, hat sich kürzlichals eine vielversprechende Strategie zur Funktionalisierung dieser Kohlenstoffnanomaterialien und der Modifizierung ihrer Eigenschaften herausgestellt. Hier zeigen wir, dass der reversible Disulfidaustausch,der unter milden Bedingungen abläuft, ideal geeignet ist, um relativ große Mengen mechanisch verzahnter Disulfidmakrozyklen auf den eindimensionalen Nanorçhren zu platzieren. Vermutlicha ls Folge der Fehlerkorrektur und der Anwesenheit von relativ starren, gebogenen p-Systemen in unseren Schlüsselbausteinen, konnten wir Beweise fürdie grçßenselektive Funktionalisierung von SWCNTs mit unterschiedlichem Durchmesser beobachten. Eine Kombination aus UV/vis/NIR, Raman, Photolumineszenz-Anregung (PLE) und transienten Absorptionsspektroskopien zeigte,d ass die kleinen (6,4)-SWCNTs überwiegend von den kleinen Makrozyklen 1 2 umschlossen wurden, wohingegen die grçßeren (6,5)-SWCNTs ideal fürd ie grçßeren Makrozyklen 2 2 schienen. Die Beobachtung der Grçßenselektivität, die computerchemisch rationalisiert wurde, kçnnte sich fürd ie Reinigung von Nanorçhrengemischen als nützlich erweisen, da wir in der Lage waren, die Disulfidmakrozyklen quantitativ unter milden Reduktionsbedingungen zu entfernen.

Using ar eductive sidewall functionalization concept, we prepared for the first time ac ovalent inter-carbonallotrope hybrid consisting of single-walled carbon nanotubes (SWCNTs) and the endohedral fullerene Sc 3 N@C 80 .T he new compound type was characterized through av ariety of techniques including absorption spectroscopy, Raman spectroscopy, TG-MS,T G-GC-MS,a nd MALDI-TOF MS. HRTEM investigations were carried out to visualizet his highly integrated architecture.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.