Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO₂, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

The general mechanism of chemical sensing is based on molecular recognition linked to different transduction strategies based on electrochemical, optical, gravimetric or thermal effects that can convert the signal to digital information. Electrochemical sensors support accurate, fast, and inexpensive analytical methods with the advantages of being easily embedded and integrated into electronics, and having the greatest potential impact in the areas of healthcare, environmental monitoring (e.g. electronic noses), food packaging and many other applications (E. Bakker and Y. Qin, Anal. Chem., 2006, 78, 3965).¹ Nanoscale electrochemical biosensors offer a new scope and opportunity in analytical chemistry. The reduction in the size of electrochemical biosensors to nanoscale dimensions expands their analytical capability, allowing the exploration of nanoscopic domains, measurements of local concentration profiles, detection in microfluidic systems and in vivo monitoring of neurochemical events by detection of stimulated dopamine release (R. Kennedy, L. Huang, M. Atkinson and P. Dush, Anal. Chem., 1993, 65, 1882).² This article reviews both state of art developments in electrochemical nanosensing, and the industrial outlook.

Graphene and its derivatives combine a numerous range of supreme properties that can be useful in many applications. The purpose of this review is to analyse the photoelectrochemical properties of pristine graphene, graphene oxide (GO) and reduced graphene oxide (rGO) and their impact on semiconductor catalysts/quantum dots. The mechanism that this group of materials follows to improve their performance will be cleared by explaining how those properties can be exploited in several applications such as photo-catalysts (degradation of pollutants) and photovoltaics (solar cells).

Graphene attracts intensive interest globally across academia and industry since the award of the Nobel Prize in Physics 2010. Within the last half decade, there has been an explosion in the number of scientific publications, patents and industry projects involved in this topic. On the other hand, energy is one of the biggest challenges of this century and related to the global sustainable economy. There are many reviews on graphene and its applications in various devices, however, few of the review articles connect the intrinsic properties of graphene with its energy. The IUPAC definition of graphene refers to a single carbon layer of graphite structure and its related superlative properties. A lot of scientific results on graphene published to date are actually dealing with multi-layer graphenes or reduced graphenes from insulating graphene oxides (GO) which contain defects and contaminants from the reactions and do not possess some of the intrinsic physical properties of pristine graphene. In this review, the focus is on the most recent advances in the study of pure graphene properties and novel energy solutions based on these properties. It also includes graphene metrology and analysis of both intellectual property and the value chain for the existing and forthcoming graphene industry that may cause a new ‘industry revolution’ with the strong and determined support of governments and industries across the European Union, U. S., Asia and many other countries in the world.

The energy and power requirements of portable electronic devices and electric vehicles are ever increasing, driving research into novel battery structures with increased volumetric energy and power densities. Existing energy storage technologies cannot satisfy both of these requirements. There are many reports on the application of graphene in batteries and supercapacitors with enhanced power and energy densities; however, few results were shown on the performance of an electrochemical energy storage device made of monolayer graphene. The energy storage capability of monolayer graphene is investigated in this paper and it can contribute an understanding of the application of graphene materials in high energy and power density batteries. In parallel, flexible solid-state batteries will relax design constraints, giving the freedom to create new device form factors. A mechanically flexible all-solid state battery can be made of monolayer graphene grown by chemical vapour deposition (CVD) directly onto copper (Cu) foil. The total thickness of the resulting battery was ∼50 μm. Such an ultrathin battery showed the highest energy density of 10 W h L⁻¹ and the highest power density of 300 W L⁻¹. It also shows excellent cyclic stability and sustains a discharge current density of 100 μA cm⁻² over 100 cycles, maintaining energy capacity over 0.02 mA h cm⁻².