Publications by authors named "Chunbo Ran"

The chemical originals of natural superhydrophobic surfaces are based on botanic or animal wax or fat, which have poor chemical and thermal resistance. Herein, we report a simple chemical modification of stearic acid (STA) with γ-aminopropyl triethoxysilane (APTES), to obtain an organic-inorganic molecular hybrid STA-APTES compound. A flower-like hierarchically structured surface with superhydrophobicity can be obtained simply by casting the STA-APTES solution under ambient circumstance.

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This paper reports a systematic study on the relationship between surface structure and wetting state of ordered nanoporous alumina surface. The wettability of the porous alumina is dramatically changed from hydrophilicity to hydrophobicity by increasing the hole diameter, while maintaining the hole interval and depth. This phenomenon is attributed to the gradual transition between Wenzel and Cassie states which was proved experimentally by comparing the wetting behavior on these porous alumina surfaces.

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Thermochemical hole burning (THB) memory is an ultrahigh density data storage technique based on the scanning tunneling microscope (STM). It utilizes the STM current to induce localized thermochemical decomposition of TCNQ-based charge transfer (CT) complexes and sequentially create nanometer-sized holes as information bits. The writing reliability and hole size depend on many factors, including the properties of the storage materials and the STM tip, and the tip-sample distance and interaction.

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We demonstrate here the thermochemical hole burning (THB) effect on a series of N-substituted morpholinium 7,7,8,8-tetracyanoquinodimethane charge-transfer (C-T) complexes for ultra-high-density data storage. A correlation between the decomposition temperature of the charge-transfer complex and the threshold voltage of hole burning was observed: the higher the decomposition temperature, the larger the writing threshold value, suggesting the possibility of molecular design for optimizing the hole burning performance. The macroscopic decomposition properties of these charge-transfer complexes were studied by thermal gravimetry combined with mass spectrometry.

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The present article describes a thermochemical hole burning (THB) effect on a charge-transfer complex triethylammonium bis-7,7,8,8-tetracyanoquinodimethane (TEA(TCNQ)(2)) using single-walled carbon nanotube (SWNT) scanning tunneling microscopy (STM) tips, which demonstrates the possibility of optimizing the THB storage materials and the writing tips for ultrahigh-density data storage. TEA(TCNQ)(2) is proven to be a high-performance THB storage material, which gives deeper holes and larger hole depth-to-diameter ratio as compared to the previous materials dipropylammonium bis-7,7,8,8-tetracyanoquinodimethane and N-methyl-N-ethylmorpholinium bis-7,7,8,8-tetracyanoquinodimethane. Instead of conventional Pt/Ir STM tips, SWNT tips made by a unique chemical assembly technique we developed have been shown to be excellent writing tips for greatly decreasing the hole sizes and increasing the storage density.

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