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Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Guided assembly of nanoparticles on electrostatically charged nanocrystalline diamond thin films | Verveniotis et al. Nanoscale Research Letters 2011 6 144 http www.nanoscalereslett.eom content 6 1 144 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Guided assembly of nanoparticles on electrostatically charged nanocrystalline diamond thin films Elisseos Verveniotis Alexander Kromka Martin Ledinský Jan Cermák Bohuslav Rezek Abstract We apply atomic force microscope for local electrostatic charging of oxygen-terminated nanocrystalline diamond NCD thin films deposited on silicon to induce electrostatically driven self-assembly of colloidal alumina nanoparticles into micro-patterns. Considering possible capacitive sp2 phase and spatial uniformity factors to charging we employ films with sub-100 nm thickness and about 60 relative sp2 phase content probe the spatial material uniformity by Raman and electron microscopy and repeat experiments at various positions. We demonstrate that electrostatic potential contrast on the NCD films varies between 0.1 and 1.2 V and that the contrast of more than 1 V as detected by Kelvin force microscopy is able to induce self-assembly of the nanoparticles via coulombic and polarization forces. This opens prospects for applications of diamond and its unique set of properties in self-assembly of nano-devices and nano-systems. Introduction Electrostatic charging of surfaces is widely used in a variety of technological processes. It improves wetting of plastics for painting it is employed in electronics e.g. in detectors or memory devices and it is used in printers and copiers for toner positioning on paper. In this context electrostatic charging has been also explored as an effective method for guiding self-assembly of micro-and nanosized elements on insulating materials 1-3 . Electrostatic charging can be generated by various methods laser ion or electron beam illumination diverse electrodes etc. . Charged patterns of sub-micrometer dimensions can be created using nanometer-sized probes such as those employed