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- ItemSelf-Assembled Flexible and Integratable 3D Microtubular Asymmetric Supercapacitors(Chichester : John Wiley and Sons Ltd, 2019) Li, F.; Wang, J.; Liu, L.; Qu, J.; Li, Y.; Bandari, V.K.; Karnaushenko, D.; Becker, C.; Faghih, M.; Kang, T.; Baunack, S.; Zhu, M.; Zhu, F.; Schmidt, O.G.The rapid development of microelectronics has equally rapidly increased the demand for miniaturized energy storage devices. On-chip microsupercapacitors (MSCs), as promising power candidates, possess great potential to complement or replace electrolytic capacitors and microbatteries in various applications. However, the areal capacities and energy densities of the planar MSCs are commonly limited by the low voltage window, the thin layer of the electrode materials and complex fabrication processes. Here, a new-type three-dimensional (3D) tubular asymmetric MSC with small footprint area, high potential window, ultrahigh areal energy density, and long-term cycling stability is fabricated with shapeable materials and photolithographic technologies, which are compatible with modern microelectronic fabrication procedures widely used in industry. Benefiting from the novel architecture, the 3D asymmetric MSC displays an ultrahigh areal capacitance of 88.6 mF cm−2 and areal energy density of 28.69 mW h cm−2, superior to most reported interdigitated MSCs. Furthermore, the 3D tubular MSCs demonstrate remarkable cycling stability and the capacitance retention is up to 91.8% over 12 000 cycles. It is believed that the efficient fabrication methodology can be used to construct various integratable microscale tubular energy storage devices with small footprint area and high performance for miniaturized electronics.
- ItemApplications of 2D-Layered Palladium Diselenide and Its van der Waals Heterostructures in Electronics and Optoelectronics(Berlin ; Heidelberg [u.a.] : Springer, 2021) Wang, Y.; Pang, J.; Cheng, Q.; Han, L.; Li, Y.; Meng, X.; Ibarlucea, B.; Zhao, H.; Yang, F.; Liu, H.; Liu, H.; Zhou, W.; Wang, X.; Rümmeli, M.; Zhang, Y.; Cuniberti, G.The rapid development of two-dimensional (2D) transition-metal dichalcogenides has been possible owing to their special structures and remarkable properties. In particular, palladium diselenide (PdSe2) with a novel pentagonal structure and unique physical characteristics have recently attracted extensive research interest. Consequently, tremendous research progress has been achieved regarding the physics, chemistry, and electronics of PdSe2. Accordingly, in this review, we recapitulate and summarize the most recent research on PdSe2, including its structure, properties, synthesis, and applications. First, a mechanical exfoliation method to obtain PdSe2 nanosheets is introduced, and large-area synthesis strategies are explained with respect to chemical vapor deposition and metal selenization. Next, the electronic and optoelectronic properties of PdSe2 and related heterostructures, such as field-effect transistors, photodetectors, sensors, and thermoelectric devices, are discussed. Subsequently, the integration of systems into infrared image sensors on the basis of PdSe2 van der Waals heterostructures is explored. Finally, future opportunities are highlighted to serve as a general guide for physicists, chemists, materials scientists, and engineers. Therefore, this comprehensive review may shed light on the research conducted by the 2D material community.
- ItemPotential and Actual impacts of deforestation and afforestation on land surface temperature(Hoboken, NJ : Blackwell Publishing Ltd, 2016) Li, Y.; Zhao, M.; Mildrexler, D.J.; Motesharrei, S.; Mu, Q.; Kalnay, E.; Zhao, F.; Li, S.; Wang, K.
- ItemEuPRAXIA Conceptual Design Report(Berlin ; Heidelberg : Springer, 2020) Assmann, R. W.; Weikum, M. K.; Akhter, T.; Alesini, D.; Alexandrova, A. S.; Anania, M. P.; Andreev, N. E.; Andriyash, I.; Artioli, M.; Aschikhin, A.; Audet, T.; Jafarinia, F. J.; Jakobsson, O.; Jaroszynski, D. A.; Jaster-Merz, S.; Joshi, C.; Kaluza, M.; Kando, M.; Karger, O. S.; Karsch, S.; Khazanov, E.; Bacci, A.; Khikhlukha, D.; Kirchen, M.; Kirwan, G.; Kitégi, C.; Knetsch, A.; Kocon, D.; Koester, P.; Kononenko, O. S.; Korn, G.; Kostyukov, I.; Barna, I. F.; Kruchinin, K. O.; Labate, L.; Le Blanc, C.; Lechner, C.; Lee, P.; Leemans, W.; Lehrach, A.; Li, X.; Li, Y.; Libov, V.; Bartocci, S.; Lifschitz, A.; Lindstrøm, C. A.; Litvinenko, V.; Lu, W.; Lundh, O.; Maier, A. R.; Malka, V.; Manahan, G. G.; Mangles, S. P. D.; Marcelli, A.; Bayramian, A.; Marchetti, B.; Marcouillé, O.; Marocchino, A.; Marteau, F.; Martinez de la Ossa, A.; Martins, J. L.; Mason, P. D.; Massimo, F.; Mathieu, F.; Maynard, G.; Beaton, A.; Mazzotta, Z.; Mironov, S.; Molodozhentsev, A. Y.; Morante, S.; Mosnier, A.; Mostacci, A.; Müller, A. -S.; Murphy, C. D.; Najmudin, Z.; Nghiem, P. A. P.; Beck, A.; Nguyen, F.; Niknejadi, P.; Nutter, A.; Osterhoff, J.; Oumbarek Espinos, D.; Paillard, J. -L.; Papadopoulos, D. N.; Patrizi, B.; Pattathil, R.; Pellegrino, L.; Bellaveglia, M.; Petralia, A.; Petrillo, V.; Piersanti, L.; Pocsai, M. A.; Poder, K.; Pompili, R.; Pribyl, L.; Pugacheva, D.; Reagan, B. A.; Resta-Lopez, J.; Beluze, A.; Ricci, R.; Romeo, S.; Rossetti Conti, M.; Rossi, A. R.; Rossmanith, R.; Rotundo, U.; Roussel, E.; Sabbatini, L.; Santangelo, P.; Sarri, G.; Bernhard, A.; Schaper, L.; Scherkl, P.; Schramm, U.; Schroeder, C. B.; Scifo, J.; Serafini, L.; Sharma, G.; Sheng, Z. M.; Shpakov, V.; Siders, C. W.; Biagioni, A.; Silva, L. O.; Silva, T.; Simon, C.; Simon-Boisson, C.; Sinha, U.; Sistrunk, E.; Specka, A.; Spinka, T. M.; Stecchi, A.; Stella, A.; Bielawski, S.; Stellato, F.; Streeter, M. J. V.; Sutherland, A.; Svystun, E. N.; Symes, D.; Szwaj, C.; Tauscher, G. E.; Terzani, D.; Toci, G.; Tomassini, P.; Bisesto, F. G.; Torres, R.; Ullmann, D.; Vaccarezza, C.; Valléau, M.; Vannini, M.; Vannozzi, A.; Vescovi, S.; Vieira, J. M.; Villa, F.; Wahlström, C. -G.; Bonatto, A.; Walczak, R.; Walker, P. A.; Wang, K.; Welsch, A.; Welsch, C. P.; Weng, S. M.; Wiggins, S. M.; Wolfenden, J.; Xia, G.; Yabashi, M.; Boulton, L.; Zhang, H.; Zhao, Y.; Zhu, J.; Zigler, A.; Brandi, F.; Brinkmann, R.; Briquez, F.; Brottier, F.; Bründermann, E.; Büscher, M.; Buonomo, B.; Bussmann, M. H.; Bussolino, G.; Campana, P.; Cantarella, S.; Cassou, K.; Chancé, A.; Chen, M.; Chiadroni, E.; Cianchi, A.; Cioeta, F.; Clarke, J. A.; Cole, J. M.; Costa, G.; Couprie, M. -E.; Cowley, J.; Croia, M.; Cros, B.; Crump, P. A.; D’Arcy, R.; Dattoli, G.; Del Dotto, A.; Delerue, N.; Del Franco, M.; Delinikolas, P.; De Nicola, S.; Dias, J. M.; Di Giovenale, D.; Diomede, M.; Di Pasquale, E.; Di Pirro, G.; Di Raddo, G.; Dorda, U.; Erlandson, A. C.; Ertel, K.; Esposito, A.; Falcoz, F.; Falone, A.; Fedele, R.; Ferran Pousa, A.; Ferrario, M.; Filippi, F.; Fils, J.; Fiore, G.; Fiorito, R.; Fonseca, R. A.; Franzini, G.; Galimberti, M.; Gallo, A.; Galvin, T. C.; Ghaith, A.; Ghigo, A.; Giove, D.; Giribono, A.; Gizzi, L. A.; Grüner, F. J.; Habib, A. F.; Haefner, C.; Heinemann, T.; Helm, A.; Hidding, B.; Holzer, B. J.; Hooker, S. M.; Hosokai, T.; Hübner, M.; Ibison, M.; Incremona, S.; Irman, A.; Iungo, F.This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over the last four years in a unique collaboration of 41 laboratories within a Horizon 2020 design study funded by the European Union. EuPRAXIA is the first European project that develops a dedicated particle accelerator research infrastructure based on novel plasma acceleration concepts and laser technology. It focuses on the development of electron accelerators and underlying technologies, their user communities, and the exploitation of existing accelerator infrastructures in Europe. EuPRAXIA has involved, amongst others, the international laser community and industry to build links and bridges with accelerator science — through realising synergies, identifying disruptive ideas, innovating, and fostering knowledge exchange. The Eu-PRAXIA project aims at the construction of an innovative electron accelerator using laser- and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators. The foreseen electron energy range of one to five gigaelectronvolts (GeV) and its performance goals will enable versatile applications in various domains, e.g. as a compact free-electron laser (FEL), compact sources for medical imaging and positron generation, table-top test beams for particle detectors, as well as deeply penetrating X-ray and gamma-ray sources for material testing. EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities, such as linear colliders at the high-energy physics (HEP) energy frontier. Consistent with a high-confidence approach, the project includes measures to retire risk by establishing scaled technology demonstrators. This report includes preliminary models for project implementation, cost and schedule that would allow operation of the full Eu-PRAXIA facility within 8—10 years.
- ItemDiscovery of TaFeSb-based half-Heuslers with high thermoelectric performance(London : Nature Publishing Group, 2019) Zhu, H.; Mao, J.; Li, Y.; Sun, J.; Wang, Y.; Zhu, Q.; Li, G.; Song, Q.; Zhou, J.; Fu, Y.; He, R.; Tong, T.; Liu, Z.; Ren, W.; You, L.; Wang, Z.; Luo, J.; Sotnikov, A.; Bao, J.; Nielsch, K.; Chen, G.; Singh, D.J.; Ren, Z.Discovery of thermoelectric materials has long been realized by the Edisonian trial and error approach. However, recent progress in theoretical calculations, including the ability to predict structures of unknown phases along with their thermodynamic stability and functional properties, has enabled the so-called inverse design approach. Compared to the traditional materials discovery, the inverse design approach has the potential to substantially reduce the experimental efforts needed to identify promising compounds with target functionalities. By adopting this approach, here we have discovered several unreported half-Heusler compounds. Among them, the p-type TaFeSb-based half-Heusler demonstrates a record high ZT of ~1.52 at 973 K. Additionally, an ultrahigh average ZT of ~0.93 between 300 and 973 K is achieved. Such an extraordinary thermoelectric performance is further verified by the heat-to-electricity conversion efficiency measurement and a high efficiency of ~11.4% is obtained. Our work demonstrates that the TaFeSb-based half-Heuslers are highly promising for thermoelectric power generation.
- ItemTailor-made nanostructures bridging chaos and order for highly efficient white organic light-emitting diodes(London : Nature Publishing Group, 2019) Li, Y.; Kovačič, M.; Westphalen, J.; Oswald, S.; Ma, Z.; Hänisch, C.; Will, P.-A.; Jiang, L.; Junghaehnel, M.; Scholz, R.; Lenk, S.; Reineke, S.Organic light-emitting diodes (OLEDs) suffer from notorious light trapping, resulting in only moderate external quantum efficiencies. Here, we report a facile, scalable, lithography-free method to generate controllable nanostructures with directional randomness and dimensional order, significantly boosting the efficiency of white OLEDs. Mechanical deformations form on the surface of poly(dimethylsiloxane) in response to compressive stress release, initialized by reactive ions etching with periodicity and depth distribution ranging from dozens of nanometers to micrometers. We demonstrate the possibility of independently tuning the average depth and the dominant periodicity. Integrating these nanostructures into a two-unit tandem white organic light-emitting diode, a maximum external quantum efficiency of 76.3% and a luminous efficacy of 95.7 lm W−1 are achieved with extracted substrate modes. The enhancement factor of 1.53 ± 0.12 at 10,000 cd m−2 is obtained. An optical model is built by considering the dipole orientation, emitting wavelength, and the dipole position on the sinusoidal nanotexture.
- ItemCopper/iron co-catalyzed alkoxycarbonylation of unactivated alkyl bromides(London : Springer Nature, 2018) Li, Y.; Wu, X.-F.Carbonylative transformations of alkyl bromides have been explored less than those of aryl halides, in part because of the high barrier to activation of aryl bromides. Additionally, alkyl-metal reagents formed in situ can tend to undergo β-hydride elimination. Here we describe a copper/iron co-catalyzed alkoxycarbonylation of unactivated alkyl bromides. In the presence of catalytic quantities of iron and copper catalysts, primary, secondary, and tertiary alkyl bromides are carbonylatively transformed into the corresponding aliphatic esters in good yields. A potential reaction mechanism is proposed based on control experiments.
- ItemA new color image encryption scheme using CML and a fractional-order chaotic system(San Francisco, CA : Public Library of Science (PLoS), 2015) Wu, X.; Li, Y.; Kurths, J.
- ItemCity-level climate change mitigation in China(Washington : American Association for the Advancement of Science (A A A S), 2018) Shan, Y.; Guan, D.; Hubacek, K.; Zheng, B.; Davis, S.J.; Jia, L.; Liu, J.; Liu, Z.; Fromer, N.; Mi, Z.; Meng, J.; Deng, X.; Li, Y.; Lin, J.; Schroeder, H.; Weisz, H.; Schellnhuber, H.J.As national efforts to reduce CO2 emissions intensify, policy-makers need increasingly specific, subnational information about the sources of CO2 and the potential reductions and economic implications of different possible policies. This is particularly true in China, a large and economically diverse country that has rapidly industrialized and urbanized and that has pledged under the Paris Agreement that its emissions will peak by 2030. We present new, city-level estimates of CO2 emissions for 182 Chinese cities, decomposed into 17 different fossil fuels, 46 socioeconomic sectors, and 7 industrial processes. We find that more affluent cities have systematically lower emissions per unit of gross domestic product (GDP), supported by imports from less affluent, industrial cities located nearby. In turn, clusters of industrial cities are supported by nearby centers of coal or oil extraction. Whereas policies directly targeting manufacturing and electric power infrastructure would drastically undermine the GDP of industrial cities, consumption-based policies might allow emission reductions to be subsidized by those with greater ability to pay. In particular, sector-based analysis of each city suggests that technological improvements could be a practical and effective means of reducing emissions while maintaining growth and the current economic structure and energy system. We explore city-level emission reductions under three scenarios of technological progress to show that substantial reductions (up to 31%) are possible by updating a disproportionately small fraction of existing infrastructure.
- ItemThe Switch in a Genetic Toggle System with Lévy Noise(London : Nature Publishing Group, 2016) Xu, Y.; Li, Y.; Zhang, H.; Li, X.; Kurths, J.