When dielectric materials are brought into contact and then separated, they develop static electricity. For centuries, it has been assumed that such contact charging derives from the spatially homogeneous material properties (along the material's surface) and that within a given pair of materials, one charges uniformly positively and the other negatively. We demonstrate that this picture of contact charging is incorrect. Whereas each contact-electrified piece develops a net charge of either positive or negative polarity, each surface supports a random "mosaic" of oppositely charged regions of nanoscopic dimensions. These mosaics of surface charge have the same topological characteristics for different types of electrified dielectrics and accommodate significantly more charge per unit area than previously thought.

Even minute quantities of electric charge accumulating on polymer surfaces can cause shocks, explosions, and multibillion-dollar losses to electronic circuitry. This paper demonstrates that to remove static electricity, it is not at all necessary to "target" the charges themselves. Instead, the way to discharge a polymer is to remove radicals from its surface. These radicals colocalize with and stabilize the charges; when they are scavenged, the surfaces discharge rapidly. This radical-charge interplay allows for controlling static electricity by doping common polymers with small amounts of radical-scavenging molecules, including the familiar vitamin E. The effectiveness of this approach is demonstrated by rendering common polymers dust-mitigating and also by using them as coatings that prevent the failure of electronic circuitry.

In touch: the outcome of contact electrification between dielectrics depends not only on the transfer of charge but also on the transfer of material. Although only minute quantities of materials are being exchanged during contact, they can reverse the polarity of dielectrics. The reported results corroborate the mosaic model and suggest that the observations are because of the mechanical softness/hardness of the materials.

Although it is known that contact-electrified polymers can drive chemical reactions, the origin of this phenomenon remains poorly understood. To date, it has been accepted that this effect is due to excess electrons developed on negatively charged surfaces and to the subsequent transfer of these electrons to the reactants in solution. The present study demonstrates that this view is incorrect and, in reality, the reactions are driven by mechanoradicals created during polymer-polymer contact.

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Was Thales right about water? Contrary to previous reports, contact charging can occur in the absence of water. At the same time, water helps stabilize the developed charges. Water‐free conditions are realized by performing all experiments and charge measurements under oil‐immersion.

Supramolecular chemistry has progressed quite a long way in recent decades. The examination of non-covalent bonds became the focus of research once the paradigm that the observed properties of a molecule are due to the molecule itself was revised, and researchers became aware of the often quite significant influence of the environment. Mass spectrometry and gas-phase chemistry are ideally suited to study the intrinsic properties of a molecule or a complex without interfering effects from the environment, such as solvation and the effects of counterions present in solution. A comparison of data from the gas phase, i.e. the intrinsic properties, with results from condensed phase, i.e. the properties influenced by the surroundings of the molecule, can consequently contribute significantly to the understanding of non-covalent bonds. This review provides insight into the often-underestimated power of mass spectrometry for the investigation of supramolecules. Through example studies, several aspects are discussed, including determination of structure in solution and the gas phase, ion mobility studies to reveal the formation of zwitterionic structures, stereochemical issues, analysis of reactivity of supramolecular compounds in the condensed and in the gas phase, and the determination of thermochemical data.

Every year, several tens of million tonnes of polymers end up as waste. Contrary to popular belief and optimistic media stories of ever-improving recycling efforts, only a small fractionindeed, a few percent of this polymeric litter is actually being recycled and reused. In the U.S., some 3 million tonnes of plastics are recycled annually, yet over 28 million tonnes age unproductivelyif the energy of this waste could be harnessed at a moderate 50% efficiency, the greater Chicago area would glow and spark almost all year round! Fortunately, significant progress is being made in technologies that aim at retrieving energy from waste polymers. On the large, often industrial, scales, polymers are being incinerated, pyrolized, and chemically degraded. Some of these technologies can produce viable fuels at costs as low as $0.75 per gallon, some five times smaller than what Mr Smith nowadays pays at the gas pump. There is also plenty of interesting, exploratory science done at smaller scales, where polymers are used in electrostatic or piezoelectric generators, or as materials converting mechanical to chemical energy. Several proof-of-concept devices have been shown to produce enough energy to power personal electronic devices or drive laboratory-scale chemical reactions. Together, the large-and smallscale technologies constitute a realistic strategy to retrieve a sizeable fraction of energy stored in polymers that would otherwise be only presenting a serious environmental concern. Broader contextOwing to their high caloric content, the millions of tons of polymers we produceand oen discardcould constitute a viable source of energy that can be retrieved by either breaking or rearranging the orientations of constituent chemical bonds. Despite optimistic media reports, we are still harnessing only a small fraction of this energy; in the U.S. alone, some 28 million tons of polymers are simply wasted each year, translating into the loss of almost a trillion MJ of energy that could be put to productive use. This article reviews a wide range of approaches by which energy "hidden" in polymers can be retrieved or transducedexamples range from traditional polymer incineration and chemolysis to the cutting-edge research on triboelectric, piezoelectric or thermoelectric generators with applications in personal electronics, MEMS, and small-scale synthesis. While none of these approaches offers a net-positive energy balance, their synergistic deployment on scales from industrial to personal could amount to societally appreciable energy savings.