Green Approach To Produce a Graphene Thin Film on a Conductive LCD Matrix for the Oxidative Transformation of Ciprofloxacin

Abstract

This study demonstrates the use of disposed liquid crystal display (LCD) glass as a supporting matrix for the fabrication of a binder/linker free thin film graphene electrode. Graphene oxide (GO) was drop casted onto the LCD matrix and electrochemically reduced to form an ErGO–LCD electrode which was subsequently employed for the electro-Fenton oxidation of ciprofloxacin. Fourier transform infrared spectroscopy confirms the presence of (i) functional groups such as CO, N–H, CN, and C–N on the LCD matrix, (ii) attachment of GO onto the LCD, and (iii) reduction of oxygen functionalities at the surface of the ErGO–LCD electrode. Raman and X-ray photoelectron spectroscopy were performed to examine the nature and chemical composition of the GO–LCD and ErGO–LCD electrodes. Cyclic voltammetry and electrochemical impedance spectroscopic studies revealed the enhancement of the oxidation–reduction properties and reduction of charge transfer resistance (Rct 17 Ω) in the presence of [Fe­(CN)6]3–/4– redox species. Electro-Fenton results revealed that a high concentration of H2O2 (45 mg L–1) was produced at acidic pH as compared to neutral (20 mg L–1) or alkaline (15 mg L–1) conditions. Furthermore, a higher current efficiency for the production of H2O2 was found at −1.0 V (63%) as compared to −1.5 V (59%) and −2.0 V (51%). Degradation studies showed >99% removal of ciprofloxacin was observed at pH 3.5 as compared to pH 7.0 (92%) or pH 9.0 (77%) at −1.5 V. The reuse experiments suggested that the electrode is stable and reusable for more than 7 cycles of experiments. The average pseudo-first-order kinetic rate constant for seven cycles of reuse was found to be 0.017 min–1.

Hydrogen peroxide generation from O2 electroreduction for environmental remediation: A state-of-the-art review

“…The modification methods are divided into the following (Fig. 2): (1) introducing other active carbon materials to carbon support, such as carbon nanotubes (CNTs) (Zarei et al, 2009;Khataee et al, 2011;Babaei-Sati and Basiri Parsa, 2017a;Flores et al, 2017), carbon black (Darvishi et al, 2013;Soltani et al, 2013;Yu et al, 2015), acetylene black (Sheng et al, 2011;Sheng et al, 2014), and graphene (Le et al, 2015a;Le et al, 2015b;Divyapriya et al, 2018;Kim et al, 2018); (2) hetero-atoms doping, such as O (Zhou et al, 2013b;Miao et al, 2014;Lu et al, 2018), N (Fellinger et al, 2012;Lee et al, 2012;Zhong et al, 2013;Hasché et al, 2016;, F (Zhao et al, 2018a;Zhao et al, 2018b), P , B , and S (Perazzolo et al, 2015;Jiang et al, 2016;Roldán et al, 2018);(3) depositing metal oxides to carbon support (Bonakdarpour et al, 2011;Carneiro et al, 2015;Aveiro et al, 2018;Pinheiro et al, 2018). Additionally, gas diffusion electrodes (GDEs) are widely recognized as high-performance cathode configurations for various gas (O 2 (Luo et al, 2015), CO 2 , NH 3 ) electroreduction, thus its utilization for O 2 electroreduction will be reviewed.…”

“…Recently, many authors are exploiting the potential use of graphene decorated materials for H 2 O 2 electrogeneration (Le et al, 2015b;Divyapriya et al, 2017;Divyapriya et al, 2018;Garcia-Rodriguez et al, 2018). developed a GF cathode coated with electrochemically exfoliated graphene and carbon black.…”

“…The authors found the rGO modified cathode exhibited improved electrochemical properties such as an increase of the redox current and a decrease of the charge transfer resistance compared with the raw CF. Most recently, Divyapriya et al (Divyapriya et al, 2018) employed disposed liquid crystal display (LCD) glass as a substrate, deposited thin graphene on it by reducing graphene oxide (GO) electrochemically without binder/linker. A H 2 O 2 production rate of 0.23 mg cm −2 h −1 under air aeration, pH 3.5, potential of −1.5 V (vs. Ag/AgCl) was obtained.…”

“…Till now, the EF process has been widely used to treat non-biodegradable or refractory organic contaminants, such as dyes (Wang et al, 2005;Özcan et al, 2008b;Zhou et al, 2018a), pesticides and herbicides (Özcan et al, 2008a;Oturan et al, 2012;Zhao et al, 2012;Zhao et al, 2018a), phenolic compounds (Oturan et al, 2000;Zhou et al, 2013b;Divyapriya et al, 2017;, and drugs (Skoumal et al, 2009;Divyapriya et al, 2018;Garza-Campos et al, 2018;Zhou et al, 2018b). As summarized in Table SM-2, the performance of the EF process enabled by different cathodes on organic contaminants degradation was systematically summarized, with a special focus on H 2 O 2 production.…”

Promoting Oxygen Electrochemical Reduction to Hydrogen Peroxide through Fabricating Hierarchical Pores

“…For most carbon-based materials (such as carbon nanotubes (CNTs) [36]- [39] , carbon black [40]- [42] , acetylene black [43]- [44] , graphene [45]- [48] and carbon fiber [49] ), the 2e-overpotential of O 2 conversion to H 2 O 2 is low, and the modification and regulation of carbon materials are convenient. By the introduction of nonmetal impurity atoms (such as O [50]- [52] , N [53]- [57] , F [58]- [59] , P [60] , B [61] , S [62]- [64] , etc.) or the introduction of metal oxides [65]- [68] of the doping modification methods for carbon materials, we can change the physical structure or electron configuration, and reach the purpose of increasing its intrinsic activity, and obtain high efficiency, high selectivity, high stability of the 2e --ORR catalysts.…”