Plasma-Assisted Fabrication of Molecularly Imprinted NiAl-LDH Layer on Ni Nanorod Arrays for Glyphosate Detection

Abstract

An inorganic-framework molecularly imprinted NiAl layered double hydroxide (MI-NiAl-LDH) with specific template molecule (glyphosate pesticide, Glyp) recognition ability was prepared on Ni nanorod arrays (Ni NRAs) through electrodeposition followed by a low-temperature O2 plasma treatment. The freestanding Ni/MI-NiAl-LDH NRA electrode had highly enhanced sensitivity and selectivity. The electrocatalytic oxidation of Glyp was proposed to occur at Ni3+ centers in MI-NiAl-LDH, and the current response depended linearly on the Glyp concentration from 10.0 nmol/L to 1.0 μmol/L (R 2 = 0.9906), with the limit of detection (LOD) being 3.1 nmol/L (S/N = 3). An exceptional discriminating capability with tolerance for other similar organophosphorus compounds was achieved. Molecular imprinting (N and P residues) affected the electronic structure of NiAl-LDH, triggering the formation of highly active NiOOH sites at relatively lower anodic potentials and substantially enhancing the electrocatalytic oxidation ability of the NiAl-LDH interface toward the C–N bonds in Glyp. In combination with the surface enrichment effect of MI-NiAl-LDH toward template molecules, the electrochemical oxidation signal intensity of Glyp increased significantly, with a greater peak separation from interfering molecules. These results challenge the common belief that the excellent performance of inorganic-framework molecularly imprinted interfaces arises from their specific adsorption of template molecules, providing new insight into the development of high-performance organic-pollutant-sensing electrodes.

Portable Integrated Sensor Based on C60 Encapsulated into Cu-Based Porphyrin-Derived MOFs for the Photoelectrochemical Detection of Glyphosate

“…Figure g shows the schematic diagram of the integrated device, which includes a power supply module, microcontroller, and current measurement circuit for PEC sensing (GLY). The photograph of the electrochemical sensing device is shown in Figure h. − All portable devices were placed in a camera obscura and used button batteries as mobile power. The current signal was displayed when the device was connected via a USB port.…”

Recent advances in layered double hydroxides‐based electrochemical sensors: Insight in transition metal contribution

“…The electrochemical responses of the optimized NiAl-NO 3 /Pt modified electrode were obtained by chronoamperometry at 0.49 V/ SCE with a sensitivity of 287 mA M À 1 cm 2 and a LoD of 1 μM for Glyp, the sensitivity found for Gluf was lower (178 mA M À 1 cm À 2 ). Very recently, Zhao et al [51] reported a new method to prepare NiAl-LDH electrode for glyphosate detection. A NiAl-LDH coating was prepared on Ni nanorods arrays (Ni-NRAs) by electrodeposition in the presence of Glyp in the electrolytic metal salts solution.…”

“…Very recently, Zhao et al. [51] reported a new method to prepare NiAl‐LDH electrode for glyphosate detection. A NiAl‐LDH coating was prepared on Ni nanorods arrays (Ni‐NRAs) by electrodeposition in the presence of Glyp in the electrolytic metal salts solution.…”

An “on-off-on” fluorescence probe for glyphosate detection based on Cu2+ modulated g-C3N4 nanosheets

“…However, these methods tend to require sophisticated instrumentation, tedious pretreatments, long testing times or tedious operation. To overcome such limitations, several techniques have been proposed (Xu et al, 2018;Qin et al, 2020;Ding et al, 2021;Wu et al, 2022;Zhao et al, 2022). Among them, fluorescence methods have been receiving great attention owing to their superior analytical performances such as simplistic, rapid, and sensitive.…”