Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

Abstract

Single layer graphite, known as graphene, is an important material because of its unique two-dimensional structure, high conductivity, excellent electron mobility and high surface area. To explore the more prospective properties of graphene, graphene hybrids have been synthesised, where graphene has been integrated with other important nanoparticles (NPs). These graphene–NP hybrid structures are particularly interesting because after hybridisation they not only display the individual properties of graphene and the NPs, but also they exhibit further synergistic properties. Reduced graphene oxide (rGO), a graphene-like material, can be easily prepared by reduction of graphene oxide (GO) and therefore offers the possibility to fabricate a large variety of graphene–transition metal oxide (TMO) NP hybrids. These hybrid materials are promising alternatives to reduce the drawbacks of using only TMO NPs in various applications, such as anode materials in lithium ion batteries (LIBs), sensors, photocatalysts, removal of organic pollutants, etc. Recent studies have shown that a single graphene sheet (GS) has extraordinary electronic transport properties. One possible route to connecting those properties for application in electronics would be to prepare graphene-wrapped TMO NPs. In this critical review, we discuss the development of graphene–TMO hybrids with the detailed account of their synthesis. In addition, attention is given to the wide range of applications. This review covers the details of graphene–TMO hybrid materials and ends with a summary where an outlook on future perspectives to improve the properties of the hybrid materials in view of applications are outlined.

Combating Hydrogen Embrittlement With Graphene Based Coatings

“…In last 10 years, a number of methods are developed for graphene synthesis by researchers. Most common techniques are Mechanical exfoliation [38], chemical synthesis [46], chemical exfoliation [47] [48], epitaxial growth [49], and thermal chemical vapor deposition (CVD) [50]. The bottom-up approach is more accurate and practical than the top-down approach as this is capable of producing nanostructures with less imperfections and better chemical composition along with its ability for mass production in large quantities [54] [55] [56].…”

Recent Progress and Future Prospects of 2D‐Based Photodetectors

“…Large‐bandgap quantum dots like CdS and ZnO were also integrated with graphene to form hybrid phototransistors, showcasing promising applications in UV detectors and image sensors with high sensitivity and gain of 10 7 –10 9 . In a recent review, various transition metal oxide (TMO) nanoparticles were also used in conjunction with graphene for different applications. Lee et al reported graphene–perovskite (CH 3 NH 3 PbI 3 ) hybrid phototransistors, which exhibited a responsivity of 180 A W −1 in the UV‐vis range, limited by the absorption range of the perovskite layer .…”

Synthesis of a zinc oxide/graphene hybrid material by the direct thermal decomposition of oxalate

“…Hybrid-or composite-materials of zinc (II) oxide (ZnO) and graphene (or, often, reduced graphene oxide) are currently of great interest in the materials science community because they are inexpensive, non-toxic, and boast a spectrum of useful applications [1][2][3]. Creating strong electronic interaction between nanoscale graphene and ZnO in a composite can significantly modify the ZnO band structure, leading to an array of exciting new properties for the bulk material.…”

“…The clean decomposition pathways of various metal oxalates have been documented for decades [37,38]. Utilizing any of these should allow for syntheses of composites with nearly any metal oxide in any stoichiometry [2], allowing for tuning of the band structures of these materials. This is, however, the subject of ongoing research.…”