Highly sensitive amperometric sensing of nitrite utilizing bulk-modified MnO 2 decorated Graphene oxide nanocomposite screen-printed electrodes

Abstract

A screen-printed amperometric sensor based on carbon ink bulk-modified with MnO2 decorated graphene oxide (MnO2/GO-SPE) nanocomposite was investigated for its ability to serve as a sensor towards nitrite. The composite was prepared by simple ultrasonication and reflux methodology and was characterized by FT-IR spectroscopy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, Atomic force microscopy and electrochemically using cyclic voltammetry, chronoamperometry and differential pulse voltammetry techniques. The MnO2/GO-SPE was found to exhibit an electro-catalytic activity for the electrochemical oxidation of nitrite in 0.1 M phosphate buffer solution (pH 7.4). The electrochemical oxidation of nitrite occurs at +0.55 V (Vs. Ag/AgCl) with a limit of detection (3σ) found to be 0.09 µM and with two linear ranges of 0.1 µM to 1 µM and 1 µM to 1000 µM with sensitivities of 1.25 µAµMˉˡcmˉ² and 0.005 µAµMˉˡcmˉ² respectively. Furthermore, the MnO2/GO-SPE showed an excellent anti-interference ability against a range of commonly encountered electroactive species and metal ions. Additionally, the fabricated MnO2/GO-SPE nitrite sensor presented excellent selectivity, reproducibility and stability. The present study widens the scope of applications of graphene-based nanocomposite materials for on-site monitoring of nitrite.

Application of Graphene-Based Materials for Detection of Nitrate and Nitrite in Water—A Review

“…Jaiswal et al succeeded in synthesizing dendritic MnO 2 nanoparticles decorated GO nanocomposites by simple mechanical stirring and this material was used to make screen printing electrodes(SPE) for nitrite detection [84]. Under the condition of applied potential of 0.55 V and pH of 7.4, the linear range of detection is 0.1-1000 µM and the detection limit is 0.09 µM.…”

Flow and Batch Injection Systems with Electrochemical Detection Applied in Drugs Determination

“…Um exemplo de aplicação do sensor foi na determinação de glicose em amostras de vinho, Trabalhos com emprego dos sistemas BIA e FIA também têm ganhado destaque com a utilização dos eletrodos impressos. 75,81 Esse tipo de eletrodo tem sido muito explorado e encontrado na literatura [93][94][95][96] principalmente por estarem acoplados a sistemas miniaturizados ganhando vantagens como fácil manuseio, economia de reagentes e menores gerações de resíduos. A utilização de eletrodos descartáveis na determinação de espécies químicas é uma área de inovação da eletroanalítica que acoplada a sistemas que automatizam as metodologias desenvolvidas, como os sistemas de injeção tornam os métodos cada vez mais rápidos e aplicáveis em grande escala.…”

Large-scale production of CdO/Cd(OH)2 nanocomposites for non-enzyme sensing and supercapacitor applications

“…This result indicates the high capability rate and applicability of the simply synthesized CdO nanocomposite compared to the previously reported supercapacitor based on CdO and/or Cd(OH) 2 nanostructures, in which the specic capacitance decreases signicantly with increasing the potential scan rate. 16,[39][40][41][42] To further estimate the specic capacitance (C s ) and to comprehend the rate capability, galvanostatic charge-discharge measurements were performed within the potential window 0.0 to À1.0 V, at different current densities in 1.0 M NaOH, and the results are presented in Fig. 7b.…”