Roles of Graphene Oxide in Heterogeneous Photocatalysis

Abstract

Graphene oxide (GO) has been widely utilized as the precursor of graphene (GR) to fabricate GR-based hybrid photocatalysts for solar-to-chemical energy conversion. However, until now, the properties and roles that GO played in heterogeneous photocatalysis have remained relatively elusive. In this Review, we start with a brief discussion of synthesis and structure of GO. Then, the photocatalysisrelated properties of GO, including electrical conductivity, surface chemistry, dispersibility, and semiconductor properties, are concisely summarized. In particular, we have highlighted the fundamental multifaceted roles of GO in heterogeneous photocatalysis, which contain the precursor of GR, cross-linked framework for constructing aerogel photocatalyst, macromolecular surfactant, two-dimensional growth template, and photocatalyst by itself. Furthermore, the future prospects and remaining challenges on developing effective GO-derived hybrid photocatalysts are presented, which is expected to inspire further research into this promising research domain.

Hierarchical ZnO Nanosheet-Reduced Graphene Oxide Composites for Photocatalytic Ethylene Oxidation

“…Recently, a combination of reduced graphene oxide (RGO) with a semiconductor is considered to be an effective method. − RGO with an excellent electron-transport property could be utilized as an electron reservoir, as well as an electron-transport mediator, which is beneficial to the transport of photoinduced electrons and retard the charge recombination . For the synthesis of RGO–ZnO composites, graphene oxide (GO) is generally utilized as a precursor.…”

Nanostructured Hybrids Based on Tantalum Bromide Octahedral Clusters and Graphene Oxide for Photocatalytic Hydrogen Evolution

“…Graphene-based photocatalysts have gained increasing interest as a viable alternative to increase the yield of photocatalytic H 2 production in solar energy conversion in chemical energy [ 28 , 29 , 30 , 31 ]. The most common photocatalysts, such as TiO 2 , CdS, and BiVO 4 , show low photocatalytic activities due to the low surface area and high recombination rate of photo-induced charge carriers owing to their band energies.…”

“…In this sense, GO is an excellent co-catalyst in photocatalytic applications due to its high surface area, excellent electronic mobility, and high adsorption ability associated with the oxygen functionalities [ 29 ]. Among photocatalytic applications of the GO-derived composites, photocatalytic degradation of pollutants and H 2 evolution from water has become the most relevant, but applications in the photoreduction of CO 2 , atmospheric ammonia synthesis, and photocorrossion suppression applications still need further exploration [ 31 , 32 , 33 , 34 ]. In mimicking the mechanism of Gratzel cells, which includes dyes as light harvesters capable of absorbing visible light and injecting electrons into the conduction band of a semiconductor material (such as TiO 2 ), it is highly desirable to develop hybrid cluster-GO photocatalysts without the need of precious metals.…”

One-Step Interfacial Integration of Graphene Oxide and Organic Chromophores into Multicomponent Nanohybrids with Photoelectric Properties

“…Among continuously expanded classes of ultrathin hybrid nanostructures, those utilizing graphene and its derivatives, graphene oxide (GO) and reduced graphene oxide (rGO), are especially promising for photocatalysis − and photovoltaic applications , because of the planarity of two-dimensional (2D) carbons and their unique electronic characteristics and optical transparency in a visible range. Owing to its chemical structure, graphene oxide is the most convenient matrix for the interfacial assembly of hybrid materials.…”