Facile design of FeCu metal-organic frameworks anchored on layer Ti3C2Tx MXene for high-performance electrochemical sensing of resorcinol

This work reports the rational design of a composite material by growing FeCu-MOF-919 on the surface of layered Ti3C2Tx MXene. The introduction of Ti3C2Tx MXene simultaneously weakens the aggregation of FeCu-MOF-919 and Ti3C2Tx MXene, which increases the electrochemical reaction active site of the composite material and improves the electrochemical activity. Interestingly, the FeCu-MOF-919/Ti3C2Tx based sensors were used to detect resorcinol (RS) with a wide linear range (0.5-152.5 μM), excellent sensitivity (0.23 μA μM-1 cm-2), low limit of detection (LOD = 0.08 μM) and outstanding stability. Meanwhile, the sensor shows high repeatability of 1.07 % RSD, reproducibility of 1.47 % RSD and anti-interference performance. What's more, the sensor can be successfully used to detect RS in tap water with good recoveries (96.25-103.37 %, RSD ≤2.18 %), demonstrating that the FeCu-MOF-919/Ti3C2Tx exhibits significant potential as an advanced sensing apparatus for the surveillance of RS in the natural environment.

Graphene Oxide-PAMAM Nanocomposite and Ionic Liquid Modified Carbon Paste Electrode: An Efficient Electrochemical Sensor for Simultaneous Determination of Catechol and Resorcinol

In this paper, a simple strategy was proposed for the analysis of catechol by a carbon paste electrode (CPE) modified with graphene oxide-third generation of poly(amidoamine) dendrimer (GO/G3-PAMAM) nanocomposite and ionic liquid (IL). The synthesis of GO-PAMAM nanocomposite was confirmed using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM), and Fourier transform infrared spectroscopy (FT-IR) techniques. The prepared modified electrode (GO-PAMAM/ILCPE) exhibited good performance to detect catechol with a notable decrease in overpotential and increase in current compared with an unmodified CPE. Under optimum experimental conditions, GO-PAMAM/ILCPE electrochemical sensors indicated a lower limit of detection (LOD) of 0.034 μM and a linear response in the concentration range of 0.1 to 200.0 µM for the quantitative measurement of catechol in aqueous solutions. In addition, GO-PAMAM/ILCPE sensor exhibited an ability to simultaneously determine catechol and resorcinol. It can be found that catechol and resorcinol could be completely separated on the GO-PAMAM/ILCPE with the differential pulse voltammetry (DPV) technique. Finally, a GO-PAMAM/ILCPE sensor was utilized to detect catechol and resorcinol in water samples with recoveries of 96.2% to 103.3% and relative standard deviations (RSDs) of less than 1.7%.

Insights into the Design and Electrocatalytic Activity of Magnesium Aluminum Layered Double Hydroxides: Application to Nonenzymatic Catechol Sensor

The design of an efficient electrocatalyst for effective trace level determinations of noxious synthetic and or biological compounds is the unceasingly noteworthy conceptual approach for rapid technology. In this work, we designed a magnesium-aluminum layered double hydroxides (Mg-Al LDHs) nanocatalyst and applied it to the electrocatalytic determination of an extremely carcinogenic catechol sensor. A coprecipitation method was employed for synthesizing the nanocatalyst, and the structure, porous nature, and morphology were confirmed by X-ray diffraction, Fourier transform infrared spectroscopy, N₂ adsorption-desorption isotherm, field emission-scanning electron microscopy, and transmission electron microscopy. The elemental composition was observed by energy dispersive X-ray analysis. The electrochemical studies were investigated with the help of cyclic voltammetry and differential pulse voltammetry techniques. The Mg-Al LDHs-based electrocatalyst was used to detect catechol by electrochemical measurements with different parameters. The proposed catechol sensor shows a wide dynamic range (0.007-200 μM) with a lower level of detection (2.3 nm) and sensitivity (3.57 μA μM^-1 cm^-2). The excellent sensor performance is attributed to the high surface area, fast electron transfer, more active sites, and excellent flexibility. This study depicts the proposed sensor as probable to practical in a scientific investigation. In addition, the modified electrode showed greater selectivity and was used in the detection of fatal contaminants in instant treatment strategies. Moreover, the Mg-Al LDHs confirmed auspicious real sample scrutiny with noteworthy retrieval outcomes in lake water samples which exposed improved consequences.