Valence band of graphite oxide

Abstract

We investigated the valence band structure of graphite oxide by photoelectron spectroscopy at the Pohang Accelerator Laboratory, Korea. The typical sp 2 hybridization states found in graphite were also seen in graphite oxide. However, the π state disappeared near the Fermi level because of bonding between the π and oxygen-related states originating from graphite oxide, indicating electron transfer from graphite to oxygen and resulting in a downward shift of the highest occupied molecular orbital (HOMO) state to higher binding energies. The band gap opening increased to about 1.8 eV, and additional oxygen-related peaks were observed at 8.5 and 27 eV. The electronic states of graphite were also found in graphite oxide. Thus, graphite oxide has an electronic structure similar to that of pristine graphite except for the states near the Fermi level and oxygen-related states.

Graphene Oxide‐mediated Fluorescence Quenching of Green Fluorescent Protein for Biomedical Applications

“…Graphene oxide with an average size of 74 µm was synthesized using a simplified Brodie method as previously described . The functional groups of GO including alcohols, epoxides, and carboxylic acids, were confirmed by Fourier transform infrared spectroscopy, 13 C nuclear magnetic resonance, and X‐ray photoelectron spectroscopy . 1‐Ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) and 1‐hydroxyl‐2,5‐dioxopyrrolidine‐3‐sulfonic acid sodium salt (sulfo‐NHS) were purchased from Sigma (St. Louis, MO, USA).…”

Increased thermal stability of cold-adapted esterase at ambient temperatures by immobilization on graphene oxide

“…GO, average size 74 μm, was prepared by the simplified Brodie method without 5 any subsequent treatment (Brodie, 1860;Jeong et al, 2008;Jeong et al, 2010). pNitrophenyl acetate, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), and hydroxy-2,5-dioxopyrrolidine-3-sulfonicacid sodium salt (sulfo-NHS) were purchased from Sigma (St. Louis, MO).…”

Beyond Adsorption: The Effect of Sulfur Doping on Emerging Applications of Nanoporous Carbons

“…3 content and configurations [19][20]. The size and ordering of the sp 2 clusters, their population in the carbon matrix, and the distortions of π states were also suggested as important.…”