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Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy

หน่วยงาน Edinburgh Research Archive, United Kingdom

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ชื่อเรื่อง : Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy
นักวิจัย : Walker, Richard John
คำค้น : electrostatically stabilised silica , sterically stabilised polystyrene colloidal systems , silica nanoparticles , colloidal suspension , rotational speed
หน่วยงาน : Edinburgh Research Archive, United Kingdom
ผู้ร่วมงาน : Koutsos, Vasileios , Blackford, Jane , Hall, Chris
ปีพิมพ์ : 2553
อ้างอิง : http://hdl.handle.net/1842/4633
ที่มา : -
ความเชี่ยวชาญ : -
ความสัมพันธ์ : -
ขอบเขตของเนื้อหา : -
บทคัดย่อ/คำอธิบาย :

In this thesis we used atomic force microscopy (AFM) to investigate systematically the behaviour of both electrostatically stabilised silica and sterically stabilised polystyrene (PS) colloidal systems on freshly cleaved mica substrates. For the silica colloidal nanoparticles we explored the effect of colloidal suspension concentration, particle size, and different application techniques on both the adsorption behaviour and subsequent structuring of the particles. For the PS colloidal nanoparticles we explored concentration effects and experimented with both dip-coating and droplet application techniques. We showed that silica nanoparticles adsorbed onto mica via irreversible adsorption that possessed lateral mobility due to the weak attraction between the nanoparticles and the substrate, facilitating subsequent capillary structuring of the nanoparticles during drying. We associated the effects of volume fraction with Debye screening, and kinetics effects with particle size and volume fraction. We also successfully imaged a partially dried film and showed the role of convective/capillary forces in the structuring of the nanoparticles. Studies with variations in particle size generated a number of different topography structures; with dewetting phenomena observed for 10 nm nanoparticles and the formation of crystalline structures for 100 nm nanoparticles. Spin coating techniques were used to produce even larger crystalline structures of nanoparticles. Size dependent ordering occurred for low concentration samples due to the polydispersity of the colloidal suspension. We showed that acceleration can affect interparticle spacing. We also studied the role of rotational speed on the crystallinity of the particle configurations and showed how fine tuning of rotational speed can generate large scale monolayer crystalline formations of nanoparticles.

บรรณานุกรม :
Walker, Richard John . (2553). Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy.
    กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom .
Walker, Richard John . 2553. "Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy".
    กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom .
Walker, Richard John . "Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy."
    กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom , 2553. Print.
Walker, Richard John . Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy. กรุงเทพมหานคร : Edinburgh Research Archive, United Kingdom ; 2553.