Fabrication of Bi-Layer Graphene and Theoretical Simulation for Its Possible Application in Thin Film Solar Cell

Abstract

High quality graphene film is fabricated using mechanical exfoliation of highly-oriented pyrolytic graphite. The graphene films on glass substrates are characterized using field-emission scanning electron microscopy, atomic force microscopy, Raman spectroscopy, UV-vis spectroscopy and Fourier transform infrared spectroscopy. A very high intensity ratio of 2D to G-band (to approximately 1.67) and narrow 2D-band full-width at half maximum (to approximately 40 cm(-1)) correspond to the bi-layer graphene formation. The bi-layer graphene/p-GaN/n-InGaN/n-GaN/GaN/sAl2O3 system is studied theoretically using TCAD Silvaco software, in which the properties of exfoliated bi-layer graphene are used as transparent and conductive film, and the device exhibits an efficiency of 15.24% compared to 13.63% for ITO/p-GaN/n-InGaN/n-GaN/GaN/Al2O3 system.

18.5% efficient graphene/GaAs van der Waals heterostructure solar cell

“…[15,21] Putting graphene over semiconductor naturally forms van der Waals Schottky diode, [21][22][23][24] which can be used as solar cells. [25][26][27][28][29] Distinct from traditional Schottky diode, the barrier height of graphene/semiconductor Schottky diode is tunable as the Fermi level of graphene and semiconductor can be adjusted independently benefiting from the nature of van der Waals contact, the low density of energy states near Dirac point and small screening length of graphene. [30,31] Although the tunable barrier height is the key to the physical picture of graphene/semiconductor Schottky diode, and structures with thin metal, ferroelectric polymer and ionic liquid as gating layer have been employed in graphene based electronic and optoelectronic devices [32][33][34][35][36][37][38][39][40], its applications in solar cell has not been explored systemically and the performance needs to further improved.…”

Recent Advances in Growth and Modification of Graphene‐Based Energy Materials: From Chemical Vapor Deposition to Reduction of Graphene Oxide

“…Considering the influence of graphene lattice structure on device performance, these methods share similarities with CVD and reduction of graphene oxide methods in improving device performances. For example, the graphene prepared by epitaxial growth, mechanical exfoliation, and organic synthesis has relatively good lattice structure, so the applications and effects are similar to those of CVD‐graphene . However, the low yield and complicated modification process hinder their usage in energy devices.…”

“…For example, the graphene prepared by epitaxial growth, mechanical exfoliation, and organic synthesis has relatively good lattice structure, so the applications and effects are similar to those of CVD-graphene. [111] However, the low yield and complicated modification process hinder their usage in energy devices. Meanwhile, the liquid phase-and electrochemically exfoliated graphene have similar expressions with rGO on energy-related application due to the contaminated or damaged lattice structure.…”

A novel absorption spectrometric method, based on graphene nanomaterials, for detection of hepatocellular carcinoma-specific T lymphocyte cells

“…[14][15][16] With its two-dimensional matrix structure, graphene is considered to be a single layer of stripped graphite 17 and plays multiple roles in biomedical applications through introducing hydroxyl, carbonyl, and epoxy groups, 18,19 as well as in antibodies, medicines, and functional nanoparticles. 16,20,21 For example, graphene can be loaded with hemin through a π-π conjugation effect, 22,23 and the amino groups in streptavidin can be reacted with carboxyl groups on modified graphene. 24,25 A biotinylated MHC monomer, thus, can be loaded onto a graphene surface through biotin-streptavidin effect.…”