An effective formaldehyde gas sensor based on oxygen-rich three-dimensional graphene

Abstract

Three-dimensional (3D) graphene with a high specific surface area and excellent electrical conductivity holds extraordinary potential for molecular gas sensing. Gas molecules adsorbed onto graphene serve as electron donors, leading to an increase in conductivity. However, several challenges remain for 3D graphene-based gas sensors, such as slow response and long recovery time. Therefore, research interest remains in the promotion of the sensitivity of molecular gas detection. In this study, we fabricate oxygen plasma-treated 3D graphene for the high-performance gas sensing of formaldehyde. We synthesize large-area, high-quality, 3D graphene over Ni foam by chemical vapor deposition (CVD) and obtain freestanding 3D graphene foam after Ni etching. We compare three types of strategies—non-treatment, oxygen plasma, and etching in HNO3 solution—for the posttreatment of 3D graphene. Eventually, the strategy for oxygen plasma-treated 3D graphene exceeds expectations, which may highlight the general gas sensing based on chemiresistors.

Applications of Graphene in Five Senses, Nervous System, and Artificial Muscles

“…Second, synthesis methods have been developed and evolved for producing graphene of different morphologies, e.g., 0D quantum dots, , 1D nanoribbons, 2D planar films, , 3D porous graphene, , or foams , and macroscale films, by several approaches including flash joule heating, , laser processing, exfoliation, , reduced graphene oxides, and chemical vapor deposition. ,− The low-cost carbon sources such as plastics and biomass waste provide more choices of carbon feedstock for conversion into graphene . The growth of graphene on metals requires the transfer to arbitrary substrates. , Quasistatic equilibrium was found as a core concern for achieving controlled chemical vapor deposition of graphene.…”

“…99 Often the graphene based gas sensors do not require heating for gas detection, which reduces the complex of the miniaturized apparatus. 11,100 The chemical vapor deposition derived graphene films are compatible with wafer-scale fabrication of transistor arrays, which can be easily tailored with surface immobilization of antibodies for biosensing. 101,102 The limitations remain in controlled synthesis of graphene with homogeneity in each form.…”

“…Indeed, graphene based transistors − and chemiresistors , have been proof of the concept for achieving the five senses (Scheme ) that lead to the perception of the physical world by animals and people.…”

Applications of MXenes in human-like sensors and actuators

“…Besides, the active composite layer consists of conductive polymers [244] and additive materials such as MXene [245,246], graphene [247][248][249][250], and other low-dimensional carbon nanostructures [251][252][253]. One can investigate the potential of biodegradation in additives and dielectrics [254,255].…”

Research progress in the synthesis and biological application of quantum dots

“…The unique physical and chemical properties of graphene materials have led to many different synthesis methods 235–238 since their emergence, and the application range is also expanding, including biomedicine, 239,240 sensing, 241,242 catalysis 243 and so on. Graphene quantum dots (GQDs) are also a member of the carbon-based nanomaterial family.…”