Ultrasensitive and stable all graphene field‐effect transistor‐based Hg²⁺ sensor constructed by using different covalently bonded RGO films assembled by different conjugate linking molecules

Abstract

As "molecular bridge," coupling agents can not only realize the covalent connection of composites, but also affect their properties, thus affecting the properties of devices based on them. Herein, leveraging differences in charge conduction properties of the (3‐aminopropyl)trimethoxysilane and 5,10,15,20‐tetrakis(4‐aminophenyl)‐21H,23H‐porphine caused by conjugacy structural differences, two kinds of layer‐by‐layer assembled smart carbon materials with different electrical properties are obtained at the same reduction temperature. The two graphene ultrathin films are then “planted” on Si/SiO2 substrates, respectively, as semiconductor layer and source/drain electrodes to fabricate an ultra‐stable all‐graphene field effect transistor (AG‐FET). Enabled by the covalent functionalized configuration and the functionally diverse of coupling agents, the AG‐FET obtained by this simple method won the high electrical characteristics, the hole, electron mobility, and the shelflife could reach 3.79 cm2/(V·s), 3.78 cm2/(V·s), and 18 months, respectively. In addition, good material stability and excellent device structure endow the device exceptional stability, electrical stability, and solvent resistance, improving its application prospect in solution phase sensing/detection. Such characteristics could be used to sense, transduce, and respond to external stimuli, especially in solution phase to monitor the important analytes, such as Hg2+ in a flowing sewage environment. We believe that such easy‐to‐manufacture AG‐FETs with ultrahigh performance and ultrahigh stability could also show great application prospects in other significant fields.

2D Covalent Organic Frameworks: From Synthetic Strategies to Advanced Optical‐Electrical‐Magnetic Functionalities

“…Graphene, which is generally regarded as one of the first 2D materials, has shown remarkable physical and optoelectronic properties. [ 110,179,180 ] Since its experimental discovery and characterization, the study and exploration of 2D materials have attracted increasing interests. [ 181 ] Hitherto, a great variety of 2D materials have been discovered and enriched the families of 2D materials, including porous layered materials of MOFs and COFs, boron nitride, transition metal dichalcogenide, MXenes, and so on.…”

Organic Semiconductor Crystal Engineering for High‐Resolution Layer‐Controlled 2D Crystal Arrays

“…[ 7,9,12,13,16,18–26 ] Therefore, the 2DOSCs can open a new window for high‐performance organic field‐effect transistor (OFETs), [ 7,11,13,18,19,21–24,27,28 ] organic phototransistors, [ 14,15,29,30 ] organic light‐emitting diodes, [ 8,31,32 ] photodetectors, [ 33–35 ] and sensors. [ 7,36,37 ] To realize the application of 2DOSCs, the fabrication of high‐resolution 2DOSC arrays is necessary because the well‐separated 2DOSCs remove the cross‐talk between surrounding devices, decrease leakage current, and reduce power consumption. [ 8,18,38–41 ] Furthermore, the cost of production needs to be addressed as well.…”

MnO2 Nanowires Anchored with Graphene Quantum Dots for Stable Aqueous Zinc-Ion Batteries

“…The GQDs were further characterized by Raman spectroscopy (Figure b). The peaks centered at 1384 and 1583 cm –1 are attributed to the D band and G band, relating to the destruction of the sp 2 network by the sp 3 -bonded C atoms and the vibration of sp 2 -bonded C atoms, respectively. − Also, the relative intensity of the D band to G band ( I D / I G ) is evaluated to be 0.95, indicating a high degree of graphitization. Moreover, XPS is carried out to determine the composition of GQDs.…”