Optimizing Bismuth-Modified Graphene-Carbon Nanotube Composite-Coated Screen Printed Electrode for Lead-Ion Sensing through the Experimental Design Strategy

Abstract

A three-dimensional graphene-carbon nanotube (G-CNT) composite-coated screen printed electrode (SPE) is developed as the substrate for bismuth-modified electrodes to measure trace lead ions in this work. This G-CNT/SPE is modified with Nafion and then deposited with Bi nanoparticles, denoted as Bi/Nafion/G-CNT/SPE. Due to smooth electron pathways and effective exposure of Bi nanoparticles on G-CNT and the negative charge of Nafion, the Pb2+-sensing ability of Bi/Nafion/G-CNT/SPE is over 50 times of that of a Bi-deposited SPE electrode, which can be further optimized by the experimental design strategy combining the fractional factorial design (FFD) and the steepest ascent path (SAP) studies. In the FFD study, the concentration of Nafion and pH of the stripping buffer solution are identified to be the key factors affecting the stripping current of lead pre-deposited onto Bi/Nafion/G-CNT/SPE. From the SAP study, a simple but reliable model for increasing the lead-ion sensitivity of Bi/Nafion/G-CNT/SPE has been constructed. The highest stripping current response of lead-ion sensing on Bi/Nafion/G-CNT/SPE can be obtained when 0.3% Nafion and the stripping buffer solution with pH = 4.75 are employed.

Nanoparticles-Modified Chemical Sensor Fabricated on a Flexible Polymer Substrate for Cadmium(II) Detection

“…Such enhancement was likely attributable to both the increment of surface area (associated with Bi nanoparticles) and the improvement of ion exchange (associated with Nafion). A similar observation has also been reported by other researchers [19,20,21].…”

Nanostructured Bi Grown on Epitaxial Graphene/SiC

“…The strong spin–orbit coupling (SOC) on the surface of Bi results in significant splitting of surface-state bands, exhibiting possible applications in thermoelectric devices and spintronics. − The ultrathin Bi film (bismuthene) was identified as a candidate for a new high-temperature quantum spin Hall (QSH) paradigm . It is also worth mentioning that Bi is an environmentally friendly element and has been proposed to be used as an electrode for sensing noxious metals . Thus Bi is an ideal material for the prospective exploitation in nanoelectronics. − In fact, the electronic states and physical properties of Bi nanostructures are closely related to the surface orientation, and the controllable fabrication is essential to the applications.…”

“…12 It is also worth mentioning that Bi is an environmentally friendly element and has been proposed to be used as an electrode for sensing noxious metals. 13 Thus Bi is an ideal material for the prospective exploitation in nanoelectronics. 14−17 In fact, the electronic states and physical properties of Bi nanostructures are closely related to the surface orientation, and the controllable fabrication is essential to the applications.…”

Rare Elements Electrochemistry: The Development of a Novel Electrochemical Sensor for the Rapid Detection of Europium in Environmental Samples Using Gold Electrode Modified with 2-pyridinol-1-oxide

“…It has been widely employed in biological matrixes, [15][16] pharmaceutical 17 and some drugs containing tertiary amine functional group 15,[18][19][20] due to its continuance, sensitivity, reproducibility and selectivity towards many target analytes. 15,19,[21][22] Electrochemical determination has been carried out at gold electrodes owing to its wide potential window, strong adsorption tendency, low background current and easy maintenance.…”