微波促进无溶剂无催化条件下2,4,5-三芳基取代咪唑衍生物的合成

咪唑及其衍生物具有广泛的生理活性,作为许多天然酶的活性中心功能基,它们参与了一系列重要的生物化学反应[1,2],被誉为“生物配体”或“生物催化剂”。近年来,人们发现咪唑及其衍生物也是一类重要的有机功能材料,它在制药、化学发光、有机光电等领域有着广泛的应用[3,4]。利用     

No-catalyst growth of vertically-aligned A1N nanocone field electron emitter arrays with high emission performance at low temperature

The A1N nanostructures with a wide band-gap of 6.28 eV are considered as ideal cold cathode materials because of their low electron-affinity. Many methods have been devoted to fabricating A1N nanostructures, but high growth temperature over 800℃ and the use of the catalysts in most methods limit their practical application and result in their poor field-emission behaviours in uniformity. This paper reports that without any catalysts, a simple chemical vapour deposition method is used to synthesize aligned A1N nanocone arrays at 550℃ on silicon substrate or indium tin oxide glass. Field emission measurements show that these nanocones prepared at low temperature have an average turn-on field of 6 V/μm and a threshold field of 11.7 V/μm as well as stable emission behaviours at high field, which suggests that they have promising applications in field emission area.     

No-catalyst growth of vertically-aligned AlN nanocone field electron emitter arrays with high emission performance at low temperature

The AlN nanostructures with a wide band-gap of 6.28 eV are considered as ideal cold cathode materials because of their low electron-affinity. Many methods have been devoted to fabricating AlN nanostructures, but high growth temperature over 800°C and the use of the catalysts in most methods limit their practical application and result in their poor field-emission behaviours in uniformity. This paper reports that without any catalysts, a simple chemical vapour deposition method is used to synthesize aligned AlN nanocone arrays at 550°C on silicon substrate or indium tin oxide glass. Field emission measurements show that these nanocones prepared at low temperature have an average turn-on field of 6 V/μm and a threshold field of 11.7 V/μm as well as stable emission behaviours at high field, which suggests that they have promising applications in field emission area.