Graphite Intended for Green Engineering Developed by Noncontaminant Reverse Abrasion

Abstract

Graphite intended for green engineering was synthesized by noncontaminant reverse abrasion, which consists of graphite layers assembled with thickness controlled on SiC sandpaper as insulating substrate. Phase formation of the graphite layers was validated by X-ray diffraction studies and its finished profile by Atomic Force Microscopy (AFM). Transport parameters of only three layers were evaluated from current-voltage curves. Mathematical functions such as derivative and modulation of a signal have been built by graphite circuits using different performance principles, compared to those used with silicon devices. The trends related to electronic engineering should be achieved with design of the graphite-based devices to facilitate their mass production in the near future.

Iron Oxide-Coupled Graphite/Fe–Si Steel Structure for Analog Computing from Recycling Principle

“…Two interfaces emerged from the structure: first, Fe-Si steel/iron oxide; second, iron oxide/graphite layer. In the fabrication of the structure processed here, the following two stages were involved: (1) Lead pencil rods were used as graphite source to grow the graphite layers of three different thicknesses assembled on SiC sandpaper using the reverse abrasion technique [11], where the sizes of these layers were 0.5 cm wide and 2 cm in length.…”

“…Table 3 summarizes the finding conduction parameters where the quantity µ a V was computed, confirming that V reduced from ~10 15 to ~10 6 cm −3 , which aligns with the growing number of disorderly stacked carbon sheets in the graphite samples. For all of the graphite samples, µ a = 250 cm 2 /Vs was used [11]. Besides, phenomenological description related to the internal states at the α-Fe 2 O 3 /graphite interface, as a function the conduction polarity at each half-cycle of the sine wave, is given below: In order to know how the α-Fe 2 O 3 /graphite interface acts as conducting channel at the positive electric field applied, a nonlinear diffusion of the charge carriers is caused through the interface and limited by attractive and repulsive electrostatic forces, where oxygen vacancies are acting as positive-charge trapping sites and the negative space-charge region, being the electrostatic length, l e , results inside the graphite layer, as shown in Figure 4a.…”

“…During the accommodation of clay particles it is expected that carbon atom vacancies and lattice defects in-plane and out-plane of the graphite structure occur, which make graphite a good lubricant and a lead pencil that people use in their daily life for writing, sketching, etc. For a long time, graphite, as an isolated layer, has been well studied, but its physical properties for engineering application became available in 2016 [11]. One direction that today shows promising result is assembling graphene layers (stacked graphite) on silicon carbide (SiC) substrate by reverse abrasion technique, where the control over the coverage percentage and thickness are advantageous; here, low carrier mobility about 250 cm 2 /Vs (several order of magnitude lower than in silicon), scattering mean free path l = 235 nm, and middle conductance at room temperature might allow charge carriers to move independent of their energy and space-charge-limited conduction (SCLC) inside the graphite bulk at nearly the length from their interface.…”

Synthesis of an Aluminum Oxide-Based Functional Device Engineered by Corrosion/Oxidation Process

“…The operation in aluminum oxide-based structure has been confirmed with the practical circuit of Figure 2b. To adjust the electrical current flow through this circuit when each samples was tested, graphite-based devices dependent on their distributed resistance and assembled on SiC sheets as substrates were used as resistors [18]. To assess practical-circuit performance; an empirical technique well known as a transfer function for the analysis of the linear systems in control theory, is used here to correlate the current-voltage characteristics and internal states of each sample, where a relationship describing the charge carriers conduction under operation understands the ratio of the output variable to the input variable [19].…”