کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5362607 1503686 2013 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Photoactive layer-by-layer films of cellulose phosphate and titanium dioxide containing phosphotungstic acid
ترجمه فارسی عنوان
فیلم های لایه ای با لایه ای از سلولز فسفات و دی اکسید تیتانیوم حاوی اسید فسفات ورشو
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
چکیده انگلیسی


- Cellulose phosphate (CP) is a new, greener polyelectrolyte to form LbL films of TiO2.
- Cellulose phosphate has high affinity for TiO2 due to formation of Ti-O-P linkages.
- Photocatalytic activity and photochromism of CP-TiO2-HPW LbL films is discussed.
- Interaction between CP, TiO2 and HPW is studied using XPS and FTIR spectroscopy.
- A detailed analysis by HRTEM of the TiO2/HPW interface is presented.

A versatile layer-by-layer (LbL) procedure for the preparation of highly dispersed, adherent and porous multilayer films of TiO2 nanoparticles (NPs) and phosphotungstic acid (HPW) on a variety of substrates at room temperature was developed based on the use of cellulose phosphate (CP) as an efficient and non-conventional polyelectrolyte. UV/vis absorption spectroscopy confirmed the linear and regular growth of the films with the number of immersion cycles and a strong adsorption ability of CP towards TiO2 NPs. FTIR spectroscopy showed that HPW binds to the surface of TiO2 through the oxygen atom at the corner of the Keggin structure. XPS results showed that the interaction between TiO2 and CP is through Ti-O-P linkage. A model is proposed for the TiO2-HPW interaction based on XPS and FTIR results. FEG/SEM study of the surface morphology revealed a porous film structure with a homogenous distribution of the TiO2 NPs induced by CP. HRTEM studies showed that the resulting composite films consist of crystalline anatase and rutile phases and poly-nano-crystalline HPW with a semi-crystalline TiO2-HPW interface. These CP/TiO2 and CP/TiO2/HPW LbL films showed good photoactivity against both saturated and unsaturated species, for instance, stearic acid (SA), crystal violet (CV) and methylene blue (MB) under UV irradiation. The CP/HPW films formed on bacterial cellulose (BC) showed good photochromic response which is enhanced in presence of TiO2 due to an interfacial electron transfer from TiO2 to HPW. This simple and environmentally safe method can be used to form coatings on a variety of surfaces with photoactive TiO2 and TiO2/HPW films.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 277, 15 July 2013, Pages 111-120
نویسندگان
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