tailieunhanh - Báo cáo hóa học: " Carbon-assisted growth and high visible-light optical reflectivity of amorphous silicon oxynitride nanowires"

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: Carbon-assisted growth and high visible-light optical reflectivity of amorphous silicon oxynitride nanowires | Zhang et al. Nanoscale Research Letters 2011 6 469 http content 6 1 469 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Carbon-assisted growth and high visible-light optical reflectivity of amorphous silicon oxynitride nanowires 1 1 f -1-2 1 2 w I -2 1 Lei Zhang Tielin Shi Zirong Tang Dan Liu Shuang Xi Xiaoping Li and Wuxing Lai Abstract Large amounts of amorphous silicon oxynitride nanowires have been synthesized on silicon wafer through carbon-assisted vapor-solid growth avoiding the contamination from metallic catalysts. These nanowires have the length of up to 100 gm with a diameter ranging from 50 to 150 nm. Around 3-nm-sized nanostructures are observed to be homogeneously distributed within a nanowire cross-section matrix. The unique configuration might determine the growth of ternary amorphous structure and its special splitting behavior. Optical properties of the nanowires have also been investigated. The obtained nanowires were attractive for their exceptional whiteness perceived brightness and optical brilliance. These nanowires display greatly enhanced reflection over the whole visible wavelength with more than 80 of light reflected on most of the wavelength ranging from 400 to 700 nm and the lowest reflectivity exceeding 70 exhibiting performance superior to that of the reported white beetle. Intense visible photoluminescence is also observed over a broad spectrum ranging from 320 to 500 nm with two shoulders centered at around 444 and 468 nm respectively. Introduction Silicon oxynitride Si-O-N materials have received considerable attention due to their special physical chemical and electrical properties 1-4 . Compositionally and structurally silicon oxynitride can be regarded as the transition from silicon oxide to silicon nitride. Many of its physical properties also display a high extent of flexibility between the two extremes changing continuously with N O ratio 5 . For example the Si-O-N film .