Hierarchical Porous Graphene–Iron Carbide Hybrid Derived From Functionalized Graphene-Based Metal–Organic Gel as Efficient Electrochemical Dopamine Sensor

Abstract

A metal-organic gel (MOG) similar in constitution to MIL-100 (Fe) but containing a lower connectivity ligand (5-aminoisophthalate) was integrated with an isophthalate functionalized graphene (IG). The IG acted as a structure-directing templating agent, which also induced conductivity of the material. The MOG@IG was pyrolyzed at 600 • C to obtain MGH-600, a hybrid of Fe/Fe 3 C/FeO x enveloped by graphene. MGH-600 shows a hierarchical pore structure, with micropores of 1.1 nm and a mesopore distribution between 2 and 6 nm, and Brunauer-Emmett-Teller surface area amounts to 216 m 2 /g. Furthermore, the MGH-600 composite displays magnetic properties, with bulk saturation magnetization value of 130 emu/g at room temperature. The material coated on glassy carbon electrode can distinguish between molecules with the same oxidation potential, such as dopamine in presence of ascorbic acid and revealed a satisfactory limit of detection and limit of quantification (4.39 × 10 −7 and 1.33 × 10 −6 M, respectively) for the neurotransmitter dopamine.

Hierarchical porous metal–organic gels and derived materials: from fundamentals to potential applications

“…54 Lastly, a gel formed from Fe(NO 3 ) 3 Á6H 2 O and 5amino isophthalic acid in the presence of isophthalic acid functionalized graphene, however it was not possible to activate the pore space of this gel. 55 In another example, a Hybrid MOG was developed by the group of Tapas Maji, where the synthesis of hydrogel was achieved by electrostatic interactions between negatively charged LAPONITE s nanoclay discs and positively charged ZIF-8 nanoparticles. 56 Further, this hydrogel was utilized as a drug delivery system by preparing the hydrogel using 5fluorouracil loaded ZIF-8 particles.…”

“…54 Lastly, a gel formed from Fe(NO 3 ) 3 ·6H 2 O and 5-amino isophthalic acid in the presence of isophthalic acid functionalized graphene, however it was not possible to activate the pore space of this gel. 55…”

“…The sensing ability of MOGs is mostly studied based on the phenomena of luminescence, 423–425 including photoluminescence (fluorescence), 426–428 chemiluminescence 133,429,430 and electrochemiluminescence. 431–433 In addition to it, the signal detection and read out can also be based on electrochemistry, 54,55,434,435 colorimetry, 415 Raman spectroscopy 414 and laser desorption/ionization mass spectrometry. 407 The very first study on the potential of MOGs in sensing was presented in 2012 by Barman et al for the detection of chemical explosives like picric acid.…”

Emerging MXene@Metal–Organic Framework Hybrids: Design Strategies toward Versatile Applications

“…Numerous studies have reported the application of 2D conducting MOF and MOF hybrid-based materials for energy storage applications . There have been reports on MOF derived materials including metal oxides, heteroatom-doped (nitrogen, boron) nanoporous carbon materials, metal sulfides/phosphides, and layered double hydroxides. ,− These MOF derived materials showed potential in electrochemical applications owing to their large surface area, significant pore volume, and controlled morphologies, with a degree of tunability of redox active sites . As discussed earlier, some of the MXene/MOF derived composites were fabricated by three different strategies.…”

In Situ Detection of Released H2O2 from Living Cells by Carbon Cloth-Supported Graphene/Au–Pt Nanoparticles

“…Carbon cloth (CC) has become an attractive conductive substrate in recent years as a result of its outstanding flexibility, ultrahigh conductivity, low cost, and easy cutting, and its interlaced fibers are beneficial to the modification and growth of various functional materials . Among the nanomaterials providing improved sensitivity and operating performance, 3D graphene walls (GWs) fabricated by plasma-enhanced chemical vapor deposition (PECVD) to form a 3D maze structure has attracted increasing attention in the application of electrochemical biosensing and cell adhesion/growth platform, benefiting from its high specific surface area, good mechanical strength, free-standing architecture, and good biocompatible properties. − Compared to 2D graphene sheets (GSs), 3D GWs can immensely reduce the accumulation of GSs via the strong π–π interaction and intersheet contact resistance, which can facilitate the modification of catalytic materials, reduce the repulsive force, and enhance the mass transport between negatively charged graphene and H 2 O 2 . ,,− Unfortunately, electrochemical direct oxidation or reduction of H 2 O 2 frequently requires a relatively high overpotential, resulting in susceptibility to the effects of interfering substances coexisting in biological fluids, which also require high overpotential. To overcome the above problems, the combination of graphene and various metal nanocatalysts was used to improve the performance of biosensing, including Au nanoparticles (Au NPs), NiO nanomaterials, Fe 3 O 4 QDs, Pt nanoparticles (Pt NPs), etc.…”