The electrochemical behaviors of single-, few- and multi-layer graphene, graphene oxides, reduced graphene oxides, CVD graphene and three-dimensional graphene are discussed and critically evaluated, ...providing an up-to-date summary on the progress of the field.
•The electrochemistry of single-, few- and multi-layer graphene•The electrochemistry of graphene oxides, reduced graphene oxides•The electrochemistry of CVD graphene and three-dimensional graphene
Two dimensional (2D) materials exhibit highly useful materials properties. Graphene, single sheet transition metals dichalcogenides found plethora applications in various fields, including analytical ...chemistry. Layered black phosphorus and its single sheet variation (phosphorene) became popular material very recently due to its monoelemental composition, biocompatibility, electrochemical properties, tunable bandgap and resulting optical properties. Here we describe progress which was made towards analytical applications of black phosphorus and its single sheet counterpart, phosphorene.
•Layered black phosphorus and phosphorene show biocompatibility.•Phosphorene has interesting electrochemical properties, optical properties and tunable bandgap.•The analytical applications of black phosphorus are overviewed.
Electrocatalytic or not? Carbon nanotubes (CNTs; see figure) are at the forefront of electrochemical research, but care should be taken when describing the electrochemistry, which is often caused by ...defects or impurities. A discussion on this aspect of their chemistry as well as important applications of CNTs for sensing and energy storage are presented.
Carbon nanotubes (CNTs) are in the forefront of electrochemical research. It has become clear that an understanding of the fundamental reasons for the electrochemical activity of CNTs is essential for further progress in the field. This review provides a critical discussion of the fundamental reasons behind the electrochemical and “electrocatalytic” activity of CNTs as well as on important applications of CNTs for sensing, biosensing, and energy storage systems.
Electrocatalytic or not? Carbon nanotubes (CNTs; see figure) are at the forefront of electrochemical research, but care should be taken when describing the electrochemistry, which is often caused by defects or impurities. A discussion on this aspect of their chemistry as well as important applications of CNTs for sensing and energy storage are presented.
In the past few years, we have witnessed rapid developments in the realization of the old nanotechnology dream, autonomous nanosubmarines. These nanomachines are self-powered, taking energy from ...their environment by electrocatalytic conversion of chemicals present in the solution, self-propelled by flux of the electrons within the submarine and the hydronium ions on the surface of the nanosub, powering it in the direction opposite to that of the flux of the hydronium. These nanosubmarines are responsive to external fields, able to follow complex magnetic patterns, navigate themselves in complex microfluidic channels, follow chemical gradients, carry cargo, and communicate with each other. This minireview focuses on a discussion of the fundamentals of the electrophoretic mechanism underlying the propulsion of this sort of nanosub, as well as a demonstration of the proof-of-concept capabilities of nanosubmarines.
Top‐down methods are of key importance for large‐scale graphene and graphene oxide preparation. Electrochemical exfoliation of graphite has lately gained much interest because of the simplicity of ...execution, the short process time, and the good quality of graphene that can be obtained. Here, we test three different electrolytes, that is, H2SO4, Na2SO4, and LiClO4, with a common exfoliation procedure to evaluate the difference in structural and chemical properties that result for the graphene. The properties are analyzed by means of scanning transmission electron microscopy (STEM), Raman spectroscopy, and X‐ray photoelectron spectroscopy. We then tested the graphene materials for electrochemical applications, measuring the heterogeneous electron transfer (HET) rates with a Fe(CN)63−/4− redox probe, and their capacitive behavior in alkaline solutions. We correlate the electrochemical features with the presence of structural defects and oxygen functionalities on the graphene materials. In particular, the use of LiClO4 during the electrochemical exfoliation of graphite allowed the formation of highly oxidized graphene with a C/O ratio close to 4.0 and represents a possible avenue for the mass production of graphene oxide as valid alternative to the current laborious and dangerous chemical procedures, which also have limited scalability.
Which electrolyte? Three different electrolytes, H2SO4, Na2SO4, and LiClO4, are tested with a common exfoliation procedure to evaluate the difference in structural and chemical properties that result for graphene and graphene oxide. Use of LiClO4 during the electrochemical exfoliation of graphite allowed the formation of highly oxidized graphene with a C/O ratio close to 4.0 and represents a possible avenue for the mass production of graphene oxide as valid alternative to the current laborious and dangerous chemical procedures with limited scalability.
Two‐dimensional materials are responsible for changing research in materials science. After graphene and its counterparts, graphane, fluorographene, and others were introduced, waves of renewed ...interest in 2D binary compounds occurred, such as in metal oxides, transition‐metal dichalcogenides (most often represented by MoS2), metal oxy/hydroxide borides, and MXenes, to name the most prominent. Recently, interest has turned to two‐dimensional monoelemental structures, such as monolayer black phosphorus and, very recently, to monolayer arsenic, antimony, and bismuth. Here, a short overview is provided of the area of exponentially increasing research in arsenene, antimonene, and bismuthene, which belong to the fifth main group of elements, the so‐called pnictogens. A short review of historical work is provided, the properties of bulk allotropes of As, Sb, and Bi discussed, and then theoretical and experimental research on mono‐ and few‐layered arsenene, antimonene, and bismuthene addressed, discussing their structures and properties.
2D As, Bs, and Bi – arsenene, antimonene, and bismuthene – are monoelemental nanomaterials. Their properties depend significantly on crystal structure, on the number of layers or on the doping. They are easily obtained from their bulk counterparts or as deposited on surfaces. An overview of their properties is provided and their applications predicted.
Voltammetry of carbon nanotubes and graphene underwent significant development in the first decade of the 21st century. The initial excitement concerning the performance of the new materials was ...replaced with increasing crises in the field caused by the use of impure materials. Here, I provide a personal view of these developments and some “reality checks” for the electrochemistry of these nanomaterials. DOI 10.1002/tcr.201100027
Voltammetry of carbon nanotubes and graphene underwent significant development in the first decade of the 21st century. The initial excitement concerning the performance of the new materials was replaced with increasing crises in the field caused by the use of impure materials. Here, I provide a personal view of these developments and some “reality checks” for the electrochemistry of these nanomaterials.
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