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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 7 1 5 GRAPHENE GOES ZERO GRAVITY This November, graphene’s suit- ability for space applications will be assessed when it is subjected to ze- ro-gravity conditions in two exper- iments supported by the Graphene Flagship—a pan-European research initiative dedicated to developing new technologies based on graphene—in conjunction with the European Space Agency (ESA). In a fully student-led ex- periment, graduate students from Delft Technical University, the Netherlands, will use the vacuum and microgravi- ty environment in the ZARM Drop Tow- er, Germany, to test graphene’s perfor- mance in light sails. A capsule contain- ing the experiment will be catapulted up and down the 146-m tower, provid- ing a total of 9.3 s of weightlessness. By shining laser light on suspended graphene membranes, the experiment will test how much thrust can be gener- ated in space-like conditions, a step to- ward developing a satellite propulsion system powered by lasers or the sun. The other ex- periment will inves- tigate how graphene can improve heat transfer efficiency in loop heat pipes— cooling systems used extensively in sat- ellites and aero- space instruments— by coating the pipes’ porous metal wicks with different graphene-related materials. The aim is to use graphene to improve thermal conductivity and capillary pressure by growing a sponge in the pores of the wicks. The coated wicks will be tested in a series of low-gravity, 3-hour flights operated by ESA in partnership with Novespace, France. During flight, a spe- cially modified plane will make 30 par- abolic ascents and descents providing around 25 s of weightlessness in each parabola. graphene-flagship.eu . ONE LAYER, TWO FUNCTIONS Scientists at Vanderbilt University, Nashville, Tenn., and the Chinese Acad- emy of Sciences developed a meth- od to produce patterned, 2D materi- als that possess dual optical, magnet- ic, catalytic, or sensing capabilities. To make their multitasking materials, the team turned to the chalcogenides, up- and-coming 2D substances containing sulfur, selenium, or tellurium. Chalco- genides naturally formmonolayers that act as blank slates and can be adapted to specific applications. The research team discovered that the monolay- ers formed by platinum-selenium and copper-selenium naturally combine with nanoscale precision into alter- nating triangles with different phases: metallic and semiconductor. Because each phase has different electrical and chemical properties, two different types of molecules can bond to the ma- terial’s surface. “In general, 2D materials are ‘func- tionalized’ for specific applications by adsorbing different species of atoms or molecules on them, or by embed- ding impurities in their otherwise per- fect crystalline structure,” explains Van- derbilt professor, Sokrates Pantelides. The new method, however, allows two simultaneous functionalities in a sin- gle material—such as catalyzing a chemical reaction while serving as a sensor for a second set of molecules— opening up a new world of possibilities for device designers. vanderbilt.edu , english.cas.cn . NANOTECHNOLOGY BRIEF Nanomechanical testing equipment provider Nanomechanics Inc., Oak Ridge, Tenn., and the International Ad- vanced Research Centre for Powder Metallurgy and New Materials, India, are joining forces to establish the Ad- vanced Nanomechanical Characterization Centre in India. Marrying advanced instrumentation with fundamental and applied research expertise in small-scale and surface mechanical characterization, the venture will explore engineer- ing solutions, accelerated technology development, and commercialization. nanomechanicsinc.com , www.arci.res.in . Illustration of triangular pattern formed by the 2Dmaterial chalcogenide that enables creation of dual-function devices. Courtesy of Yu-Yang Zhang/Chinese Academy of Sciences. Two experiments being prepared by Graphene Flagship will be launched in November to test graphene in zero-gravity conditions.