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Maximized energy density: Controlled electrochemical charge injection (ECI) can be used for maximizing the energy density of supercapacitors (SCs). The electrode potential is tuned by the surface chemical structure of the electrode material to increase both the working voltage and the specific capacity of the SCs. As a result, the energy density of carbon SCs is significantly improved close to the level of lithium-ion batteries (see picture).

A goal of nanotechnology is to create nanosystems that are intelligent, multifunctional, super-small, extremely sensitive, and low power consuming. The search for sustainable power sources for driving such nanosystems is an emerging field in today s energy research, and harvesting energy from multiple sources available in the environment is highly desirable for creating self-powered nanosystems. For implanted nanodevices, such as a glucose sensor used to monitoring diabetes, it is rather challenging to power them since the solar energy is not available inside the body and thermal energy cannot be used because there is no temperature gradient. The only available energy in vivo is mechanical and biochemical energy. Nanogenerators (NGs) were demonstrated to convert low( Hz) and high-frequency ( 50 kHz) mechanical energy into electricity by means of piezoelectric zinc oxide (ZnO) nanowires (NWs). Following this landmark discovery, direct current (DC) and alternative current (AC) NGs, single-wire and multi-nanowire arrays-based NGs have been developed. On the other hand, biofuel cells have been demonstrated to convert biochemical energy into electricity by using active enzymes as catalyst and glucose as fuel. We have previously demonstrated that biochemical and mechanical generators can work together to harvest multiple kinds of energy in bio-liquid, however, the two units were separately arranged on plastic substrate without integration, and the output was too low and the size was too large to be used for real applications. Here we demonstrate a flexible fiberbased hybrid nanogenerater (hybrid NG) consisting of a fiber nanogenerator (FNG) and a fiber biofuel cell (FBFC), which can be used in bio-liquid (such as blood) for energy harvesting. The FNG and FBFC are totally integrated on a single carbon fiber for the first time for simultaneously or independently harvesting mechanical and biochemical energy. In addition, the hybrid NG can also serve as a self-powered pressure sensor for detecting pressure variation in bio-liquid. Our fiber-based hybrid NG is an outstanding example of selfpowered nanotechnology for applications in biological sciences, environmental monitoring, defense technology, and even personalized electronics. A hybrid nanogenerater made up of a fiber nanogenerater (FNG) and a fiber biofuel cell (FBFC) is designed onto a carbon fiber. The design of the FNG is based on the textured ZnO NW film grown on the surface of the carbon fiber. The carbon fiber serves not only as the substrate on which the ZnONW film is grown, but also as an electrode (noted as core electrode). In previous work we have fabricated a textured ZnO NW film by using physical vapor deposition. The FNG was fabricated by etching the ZnO NW film at one end of the carbon fiber, contacting the top surface using silver paste and tape, and leading out two electrodes from the surface and the core electrodes (left-hand in Figure 1a). An FBFC, which is used for converting chemical energy from bio-fluid such as glucose/blood into electricity, is fabricated at the other end of the carbon fiber (Figure 1a). A layer of soft epoxy polymer is coated on the carbon fiber as an insulator, then two gold electrodes are patterned onto it and coated with carbon nanotubes (CNTs), followed by immobilization of glucose oxidase (GOx) and laccase to form the anode and cathode, respectively. In comparison to conventional biofuel cells and miniature biofuel cells, the FBFCs described here were integrated with the NG (or nanodevices) on an individual carbon fiber, forming a self-powered nanosystem. And the size of the FBFCs shrank a lot due to eliminating the separator membrane and mediator. For easy handling and fabrication, we created our hybrid NG on individual carbon fibers, and our measurements were performed on a bundle of (ca. 1000) carbon fibers. The performance of the hybrid NG is characterized by measuring the short-circuit current Isc and the open-circuit voltage Voc. The FBFC outputs are given as VFBFC and IFBFC, the AC FNG outputs as VFNG and IFNG, and the hybrid NG outputs as VHNG and IHNG. When the hybrid NG is immersed into bio-liquid containing glucose, the FBFC generates a DC output. A typical FBFC output is shown in Figure 2a and b with IFBFC of ca. 100 nA and VFBFC of ca. 100 mV. When a pressure is periodically applied to the bio-liquid, the FNG starts to generate an AC output. The general output of VFNG is 3.0 Vat an output current of IFNG= 200 nA (Figure 2c and d) for an FNG made of ca. 1000 carbon fibers, and the corresponding current density is 0.06 mAcm . By integrating the AC FNG and DC FBFC, a hybrid NG is obtained with the output close to the sum of the FBFC and the FNG (Figure 2e and f). The shape and frequency of the AC FNG output are the same before and after the hybrid[*] Dr. C. Pan, Z. Li, W. Guo, Prof. Z. L. Wang School of Materials Science and Engineering Georgia Institute of Technology, Atlanta, GA 30332-0245 (USA) E-mail: zlwang@gatech.edu Homepage: http://www.nanoscience.gatech.edu/zlwang

Red glow in daylight ... chemist's delight! An efficient transfer of excitation energy from the ligand to the luminescent states of the coordinated Eu III ion in 1 occurs from the singlet excited state of the ligand. The complex shows characteristic bright red Eu-centered emission with a quantum yield of 0.52 when sensitized with visible light. link_to_subscribed_fulltext

The development of artificial photosynthetic systems that utilize solar energy is one of the most challenging goals of chemistry and material sciences. The straightforward way to construct an artificial photosynthetic device for practical solar fuel production for the practical use of solar energy is to mimic the structural and functional organization of the natural photosynthetic machinery. In photosynthetic organisms, light is initially absorbed by antenna protein–pigment complexes in which it induces an excited electronic state (exciton), and then excitons (or electron–hole pairs) are transferred by means of F rster resonance energy transfer (FRET) to specialist chlorophyll cofactors in specialized reaction centers (RCs); here, excitons dissociate into their constituent carriers which are used in chemical transformations for the synthesis of high-energy molecules that fuel the organism. An artificial device that mimics this process for solar energy conversion should include, among other components, an efficient light-harvesting antenna capable of transferring the excitation energy to the RC. Based on the principle of photosynthesis, a variety of artificial antenna systems have been developed using supramolecular chemistry in which dendrimers incorporate porphyrins or other organic fluorophores or organometallic complexes. Although efficient excitation-energy transfer was obtained in such systems, the use of organic fluorophores in light-harvesting systems is rather limited because of their narrow spectral windows for light-collecting and lack of photostability. Recently it was suggested that inorganic nanocrystals, which are able to collect light over a wide spectral window, may achieve significantly greater absorption than natural photosystems, thus enhancing and could thus be used to enhance the light-harvesting process. Simultaneously, these nanocrystals may also be very efficient in excitationenergy transfer. This has led us to contemplate the development of hybrid materials in which light energy harvested by the nanocrystals in the optical region may be transferred to the RC in order to enhance the efficiency of the photosynthetic process. The simplest and best understood photosynthetic RC is that found in purple bacteria (Rhodobacter sphaeroides, for example). Although RCs from different photosynthetic organisms vary in their structure and composition, they are always composed of complexes of pigments and proteins, and RC fromRb. sphaeroides is known to be a good model of all the photosynthetic RCs. Here, we demonstrate that photoluminescent quantum dots (QDs) of these selected photoluminescence (PL) wavelengths may be tagged with the RC of Rh. sphaeroides in such a way that FRET from the QD to the RC is realized (Figure 1). A nearly threefold increase in the rate of generation of excitons in the RC is demonstrated, and theoretical estimates predict even stronger enhancements, thus indicating that further optimization is possible. Advances in inorganic synthesis have resulted in the production of monodispersed QDs such as highly photoluminescent CdSe/ZnS core/shell and CdTe nanocrystals. The light absorption by these QDs appears as a quasicontinuous superposition of peaks with extinction coefficients orders of magnitude higher than those of organic molecules. QDs are ultrastable against photobleaching, and the quantum [*] Prof. I. Nabiev CIC NanoGUNE Consolider, 20018 San Sebastian (Spain) and EA n83798, Universit de Reims Champagne-Ardenne 51100 Reims (France) and Ikerbasque, Basque Foundation for Science 48011 Bilbao (Spain) Fax: (+34)943-574-001 E-mail: i.nabiev@nanogune.eu

however, the design andimplementation of a stable and efficient molecular wateroxidation system that operates at high catalytic turnovernumber (TON) and frequency (TOF) for extended periods ofcontrolled-potential electrolysis (CPE), with moderate over-potential and high current density, are challenging.

ZusammenfassungAuf dem Weg zur Erreichung der gesetzten Klimaziele in Deutschland muss der Anteil erneuerbarer Energien an der Stromerzeugung stetig ausgebaut werden. Die damit einhergehende zunehmende Fluktuation der Erzeugungsleistung stellt die Stromnetze vor große Herausforderungen. Da knapp 44 % des Strom- und rund ein Viertel des Wärmeverbrauchs in Deutschland auf die Industrie entfällt, bietet diese signifikantes Potenzial, Schwankungen im Stromnetz durch die Anpassung des Stromverbrauchs an das Stromangebot im Sinne von Demand Response mittels Energieflexibilität auszugleichen. Bislang erschwert neben regulatorischen Rahmenbedingungen insbesondere eine fehlende einheitliche Modellierung & Kommunikation von Energieflexibilität sowie deren Einbettung in bestehende Unternehmens-IT-Infrastrukturen eine optimale und automatisierte Vermarktung. Im Rahmen des Forschungsprojekts SynErgie wurden hierfür informationstechnische Anforderungen erhoben, Datenmodelle zur Beschreibung von Energieflexibilität und eine übergeordnete IT-Architektur entwickelt. Mit Hilfe einer unternehmensspezifischen Plattform und einer zentralen Marktplattform kann der Informations- und Kommunikationsfluss von der Maschine/Anlage bis zur Flexibilitätsvermarktung und wieder zurück abgebildet werden. Eine Vielzahl verschiedener Services unterstützt hierbei ein Unternehmen von der Identifikation bis hin zur automatisierten und standardisierten Vermarktung von Energieflexibilität. Durch die Einsatzmöglichkeiten und Wirkansätze von IT wurden Grundsteine für nachhaltigkeitsbezogene Effekte des industriellen Energieverbrauchs gelegt, welche in den kommenden Monaten in einer Modellregion in und um Augsburg mit Industrieunternehmen, Netzbetreibern und weiteren Serviceanbietern getestet werden.

Glycan moiety of glycoproteins plays an essential role in its biological activity in vivo, and the analysis of glycosylation is of great importance in the development of protein therapeutics. In this study, we report a rapid and simple detection of protein glycosylation based on the fluorescence resonance energy transfer (FRET) between concanavalin A-conjugated gold nanoparticles (ConA-AuNPs) and dextran-conjugated quantum dots (Dex-QDs). The increased photoluminescence (PL) signals of Dex-QDs due to the competitive inhibition of glycoproteins were well correlated with the glycosylation chain length of glucose oxidases as well as the mannosylation degree of bovine serum albumin (BSA). The parallel analysis of the diversely mannosylated BSAs using an image analyzer further demonstrated the potential of this new technique in high-throughput screening of glycoprotein and carbohydrate therapeutics.