Self‐Organized Graphene Nanosheets with Corrugated, Ordered Tip Structures for High‐Performance Flexible Field Emission

Abstract

Patterned reduced graphene oxide (rGO) films with vertically aligned tip structures are fabricated by a straightforward self-assembly method. The size, uniformity of the patterns, and alignment of the tips are successfully controlled according to the concentration of a GO/octadecylamine (ODA)-dispersed solution. The surface energy difference between the GO/ODA solution and a self-assembled water droplet is a critical parameter for determining the pattern structure. Numerous rGO nanosheets are formed so as to be vertically aligned with respect to the substrate during film fabrication at GO concentrations below 2.0 g/L. These samples provide high field-emission characteristics. The patterned rGO arrays are highly flexible with preservation of the field emission properties, even at large bending angles. This is attributed to the high crystallinity, emitter density, and good chemical stability of the rGO arrays, as well as the strong interactions between the rGO arrays and the substrate.

Electrochemical preparation of porous graphene and its electrochemical application in the simultaneous determination of hydroquinone, catechol, and resorcinol

“…The I D /I G ratios of P-rGO is calculated to be 0.89, lower than that of GO (1.25), reflecting the increase in size of the in-plane sp 2 domains after reduction [26]. According to the literatures, the value of I D /I G decreases after the reduction and our result is consistent with the insights of recent publications [20,27,28].…”

Enhanced response and sensitivity of self-corrugated graphene sensors with anisotropic charge distribution

“…Notably, the corrugated 2DrGO film along the walls below the height of 3 μm is not affected by the anisotropic charge distribution. In other words, the ordered, protruding rGO surfaces increased the field enhancement factor compared to flat rGO films because of a high aspect ratio caused by geometrical modification 28 . In addition, the turn-on and threshold fields of the modified rGO surfaces were higher than those of flat rGO films.…”

Laser-Patternable Graphene Field Emitters for Plasma Displays

“…However, a requirement for the graphene utilized in field electron emission devices is that the material should be vertically aligned/protrude from the polymer substrate, providing more individual field emission sites, as flat graphene sheets lack sharp edges and require a high voltage to turn on the FEE process [10]. Several methods for synthesizing graphene nanostructures on polymer substrates, such as spin-casting, electrophoresis, self-assembly, thermal welding, and filtering, have been developed and have employed the obtained nanostructures as efficient field emitters [11,12,13,14,15,16]. A cost-effective process of synthesizing graphene nanostructures on polymers using cheap precursors is needed for the industrial production of display devices.…”