کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5376327 | 1504319 | 2007 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Hydrogen activation at TiO2 anatase nanocrystals
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Hydrogen activation at TiO2 anatase nanocrystals Hydrogen activation at TiO2 anatase nanocrystals](/preview/png/5376327.png)
چکیده انگلیسی
The chemical activation of small molecules like hydrogen or oxygen at the surface of UV excited nanocrystals can provide valuable insights into the solid's photoactivity. We investigated the interaction of dehydroxylated TiO2 anatase nanocrystals with atomic as well as molecular hydrogen using electron paramagnetic resonance spectroscopy. Electron transfer from atomic hydrogen occurs spontaneously at T = 77 K and produces a charge separation state which is characterized by surface adsorbed protons and trapped electrons forming paramagnetic Ti3+ (d1) states. While there is no significant activation of molecular H2 at the surface of dehydroxylated particles in the absence of UV light, H2 acts as an efficient scavenger of photogenerated hole centers. These reactions are compared with charge carrier trapping at p < 10â5 mbar and discussed in the light of experiments which were carried out on frozen colloidal nanoparticle suspensions as described in the literature.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Physics - Volume 339, Issues 1â3, 15 October 2007, Pages 138-145
Journal: Chemical Physics - Volume 339, Issues 1â3, 15 October 2007, Pages 138-145
نویسندگان
Thomas Berger, Oliver Diwald, Erich Knözinger, Francesco Napoli, Mario Chiesa, Elio Giamello,