It is a great advantage to design advanced materials with outstanding porosity and controllable band gab. In this study, (Fe, Ti)-containing mesoporous silica (x Fe/Ti-HMS) nanoparticles were prepared by a photo-a...It is a great advantage to design advanced materials with outstanding porosity and controllable band gab. In this study, (Fe, Ti)-containing mesoporous silica (x Fe/Ti-HMS) nanoparticles were prepared by a photo-assisted deposition PAD technique, where x is a nominal composition ofFe (l to 4 wt%)). The prepared samples were characterized by DR-UV, XRD, and TEM techniques. The results showed the insertion of Fe into intra-framework of Ti-HMS resulted in a gradual narrowing of the band gap of Ti-HMS samples with increment of Fe wt%. TEM observations reveal that Fe nanoparticles are evenly distributed within Ti-HSM matrix at different Fe wt%. Such results indicate the possibility to control the band gap of a single-site photocatalyst (Ti-HMS) by coupling it with the conventional nano-sized Fe catalysts.展开更多
Various methods for production of polysilicon have been proposed for lowering the production cost andenergy consumption, and enhancing productivity, which are critical for industrial applications. The fluidized bed ch...Various methods for production of polysilicon have been proposed for lowering the production cost andenergy consumption, and enhancing productivity, which are critical for industrial applications. The fluidized bed chemical vapor deposition (FBCVD) method is a most promising alternative to conventional ones, but the homogeneous reaction of silane in FBCVD results in unwanted formation of fines, which will affect the product qualityand output. There are some other problems, such as heating degeneration due to undesired polysilicon deposition on the walls of the reactor and the heater. This article mainly reviews the technological development on FBCVD of polycrystalline silicon and the research status for solving the above problems. It also identifies a number of challenges to tackle and principles should be followed in the design ofa FBCVD reactor.展开更多
文摘It is a great advantage to design advanced materials with outstanding porosity and controllable band gab. In this study, (Fe, Ti)-containing mesoporous silica (x Fe/Ti-HMS) nanoparticles were prepared by a photo-assisted deposition PAD technique, where x is a nominal composition ofFe (l to 4 wt%)). The prepared samples were characterized by DR-UV, XRD, and TEM techniques. The results showed the insertion of Fe into intra-framework of Ti-HMS resulted in a gradual narrowing of the band gap of Ti-HMS samples with increment of Fe wt%. TEM observations reveal that Fe nanoparticles are evenly distributed within Ti-HSM matrix at different Fe wt%. Such results indicate the possibility to control the band gap of a single-site photocatalyst (Ti-HMS) by coupling it with the conventional nano-sized Fe catalysts.
基金Supported by the Natural Science Foundation of Shandong Province of China (ZR2009BM011) and the Doctor Foundation of Shandong Province of China (BS2010NJ005).
文摘Various methods for production of polysilicon have been proposed for lowering the production cost andenergy consumption, and enhancing productivity, which are critical for industrial applications. The fluidized bed chemical vapor deposition (FBCVD) method is a most promising alternative to conventional ones, but the homogeneous reaction of silane in FBCVD results in unwanted formation of fines, which will affect the product qualityand output. There are some other problems, such as heating degeneration due to undesired polysilicon deposition on the walls of the reactor and the heater. This article mainly reviews the technological development on FBCVD of polycrystalline silicon and the research status for solving the above problems. It also identifies a number of challenges to tackle and principles should be followed in the design ofa FBCVD reactor.