Similar to its popular older cousins the fullerene, the carbon nanotube, and graphene, the latest form of nanocarbon, the carbon nanodot, is inspiring intensive research efforts in its own right. These surface-passivated carbonaceous quantum dots, so-called C-dots, combine several favorable attributes of traditional semiconductor-based quantum dots (namely, size- and wavelength-dependent luminescence emission, resistance to photobleaching, ease of bioconjugation) without incurring the burden of intrinsic toxicity or elemental scarcity and without the need for stringent, intricate, tedious, costly, or inefficient preparation steps. C-dots can be produced inexpensively and on a large scale (frequently using a one-step pathway and potentially from biomass waste-derived sources) by many approaches, ranging from simple candle burning to in situ dehydration reactions to laser ablation methods. In this Review, we summarize recent advances in the synthesis and characterization of C-dots. We also speculate on their future and discuss potential developments for their use in energy conversion/storage, bioimaging, drug delivery, sensors, diagnostics, and composites.

Ionic liquids are being employed in almost all areas of chemistry and materials, yet there are inherent issues which arise if the utmost care is not taken in the preparation and purification of these materials. They are not easily synthesized and purified using the existing methods. We describe a reliable method for producing large quantities of high quality ionic liquids. Additionally, we show that imidazoliums are not 'special' due to their 'inherently fluorescent' nature, that spectroscopically clean imidazoliums are attainable, and most classes of ionic liquids do exhibit fluorescent backgrounds when extreme care is not taken during their synthesis and purification.

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Within the last decade, ionic liquids have come to the fore as environmentally-responsible designer solvents. But what are ionic liquids and what can they offer the analytical scientist? This article addresses these questions and chronicles recent progress made in the application of ionic liquids toward analytical problem-solving. While further progress is required before ionic liquids become mainstream analytical solvents, results to date commend their use in various modes of chemical analysis. It is our aim that the findings reported herein draw other researchers into this area and encourage the increased application of ionic liquids in this manner.

We report on the local microenvironment that surrounds three fluorescent solutes (i.e., the cybotactic region) when they are dissolved in a 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF 6 ]) roomtemperature ionic liquid as a function of temperature and added CO 2 (T ) 308 K; P ) 0-150 bar). In dry [bmim][PF 6 ] at 293 K, the cybotactic region exhibits a dielectric constant and refractive index of 11.4 ( 1.0 and 1.523 ( 0.025, respectively. The activation energy that describes the [bmim][PF 6 ] viscous flow is 38.4 ( 0.9 kJ mol -1 . The activation energy for solute rotational reorientation in [bmim][PF 6 ] is equivalent to the activation energy for [bmim][PF 6 ] viscous flow, indicating that solute rotational dynamics are correlated entirely with the [bmim][PF 6 ] dynamics. There is nanosecond dipolar relaxation surrounding a solute dissolved in dry [bmim][PF 6 ] at 293 K. Even though CO 2 is highly soluble in [bmim][PF 6 ] (CO 2 mole fraction ) 0.6 at 313 K and 68 bar), addition of up to 150 bar CO 2 to [bmim][PF 6 ] at 308 K causes the solute's cybotactic region dipolarity to decrease by less than 15%. At a fixed temperature (308 K), we observe a 5-fold decrease in the apparent [bmim][PF 6 ] bulk viscosity between 0 and 150 bar CO 2 .