Higher oxidation level in graphene oxide

The synthesis of graphene oxide covalently linked with nickel tetraamino phthalocyanine: A photoelectrochemical sensor for the analysis of rifampicin irradiated with blue light

“…The double peaks (3,445 and 3,373 cm −1 ) observed at 3,500-2,500 cm −1 were ascribed to the stretching vibration of the primary amine group of NiTAPc, and the signal at 1,619 cm −1 was attributed to the N-H bending vibration of free -NH 2 . [30] For GO, the symmetric and asymmetric telescopic vibrations of -COO − at 1,721 and 1,613 cm −1 agreed with the previous reports. [46] In the likely case of NiTAPc-GO, the formation of amide bonds resulted in the C=O peak of GO originally located at 1,694 cm −1 and was shifted to the lower wavenumbers.…”

“…[12][13][14][15] Photosensitive materials such as nanosemiconductors, Ru(II) complexes, organic compounds, composite photoelectric materials, and biological macromolecules [16][17][18][19] have been extensively used in the fields of bioanalysis and drug/contaminant quantitation. [30][31][32] The application of carbon material in electrochemical sensing has been widely investigated. [25][26][27] Ni tetraamino phthalocyanine (NiTAPc), produced by reduction of the corresponding tetranitro species [28] is a representative metallophthalocyanine.…”

“…The amino groups of NiTAPc allow it to be covalently linked with graphene oxide (GO) [29] to form a highly oxidized carbon material with large surface areas by using the modified Hummer's method. [30][31][32] The application of carbon material in electrochemical sensing has been widely investigated. [33][34][35] The abundance of oxygenated functional groups (e.g., carboxyl, epoxy, and hydroxy) in GO [36] makes it more reactive than graphene.…”

Improvement of the Graphene Oxide Dispersion Properties with the Use of TOPSIS Based Taguchi Application

“…Graphite (<20µm from Sigma Aldrich and <50µm from Merck), sulphuric acid (95-97%, Merck) and sodium nitrate (99.99% extra pure, Merck) has been stirred at 5°C for a several hours and then the potassium permanganate (pH 7-9, Merck) has been added the mixture with regard to Hummers and improved Hummers method [2,[31][32][33]. The deionized water has been added to the suspension and the reaction temperature has been raised to 98°C as a result of the hydration heat.…”

A highly responsive methanol sensor based on graphene oxide/polyindole composites

“…However, the electrical conductivity of GO depends on the number of oxygens in its structure and can be controlled by its band gap. 15 GO has received much interest in gas sensor applications because its structure contains various oxygen species, which provide a variety of possible active sites. These oxygen species, namely hydroxyl, carbonyl, carboxyl, and peroxide groups, provide the active sites for interaction with the methanol vapor and increase the methanol response relative to the pristine conductive polymer.…”