Fundamentals of Chemical Vapor Deposited Graphene and Emerging Applications

Abstract

Graphene, the atomically thin sheet of sp 2 hybridized carbon atoms arranged in honeycomb structure, is becoming the forefront of material research. The chemical vapor deposition (CVD) process has been explored significantly to synthesis large size single crystals and uniform films of monolayer and bilayer graphene. In this prospect, the nucleation and growth mechanism of graphene on a catalytic substrate play the fundamental role on the control growth of layers and large domain. The transition metals and their alloys have been recognized as the active catalyst for growth of monolayer and bilayer graphene, where the surface composition of such catalysts also plays critical role on graphene growth. CVD-synthesized graphene has been integrated with bulk semiconductors such as Si and GaN for the fabrication of solar cells, photodetectors, and lightemitting diodes. Furthermore, CVD graphene has been integrated with hexagonal boron nitride (hBN) and transition metal dichalcogenides (TMDCs) for the fabrication of van der Waals heterostructure for nanoelectronic, optoelectronic, energy devices, and other emerging technologies. The fundamental of the graphene growth process by a CVD technique and various emerging applications in heterostructure devices is discussed in detail.

Flexible and Stretchable Bioelectronics

“…Its Young’s modulus is 1 TPa. Graphene has excellent flexibility because the materials’ atoms are atomically thin; it also has some stretchability due to its hexagonal lattice structure [ 65 ]. However, the material’s conductivity can be destroyed by an elongation above 20%; thus, cross-linking graphene with an elastomer is important to enhance stretchability [ 66 ].…”

An electrochemical sensor for nanomolar detection of caffeine based on nicotinic acid hydrazide anchored on graphene oxide (NAHGO)

“…The electrochemical method has proved its quality and efficiency for the fabrication of sensing devices 25 , 26 . It acts as a powerful tool for detecting and monitoring the unsafe amount of organic and inorganic compounds using different carbon materials.…”

Synthesis, characterisation, and the electrochemical sensing behaviour of nicotinic acid hydrazide anchored on graphene oxide (NAHGO)

“…It makes the requirement of highly sensitive, consistent, simple, and fast methods. In correlation with carbon materials, electrochemical method has proved its quality and e ciency for the fabrication of sensing devices successfully 13,14 . Caffeine has already been electrochemically detected with boron doped diamond electrode, DNA-functionalised single walled carbon nanotubes (SWCNT), attapulgite/na on, gold nanoparticle, gold-chitosan, multiwalled carbon nanotubes (MWCNT)/diamond like carbon lms, glutathione-rGO etc 15,16,17,18,19 .…”