Self-assembly of cerium oxide nanostructures in ice molds.
The formation of nanorods, driven by the physicochemical phenomena during the freezing and after the aging of frozen ceria nanoparticle suspensions, is reported. During freezing of a dilute aqueous solution of CeO2 nanocrystals, some nuclei remain in solution while others are trapped inside micro- and nanometer voids formed within the growing ice front. Over time (2-3 weeks) the particles trapped within the nanometer-wide voids in the ice combine by an oriented attachment process to form ceria nanorods. The experimental observations are consistent with molecular dynamics simulations of particle aggregation in constrained environments. These observations suggest a possible strategy for the templated formation of nanostructures through self-assembly by exploiting natural phenomena, such as voids formed during freezing of water. This research suggests a very simple, green chemical route to guide the formation of one- and three-dimensional self-assembled nanostructures.
Karakoti
Ajay S
AS
Surface Engineering and Nanotechnology Facility, Advanced Materials Processing and Analysis Center, Department of Mechanical Materials and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA.
Kuchibhatla
Satyanarayana V N T
SV
Baer
Donald R
DR
Thevuthasan
Suntharampillai
S
Sayle
Dean C
DC
Seal
Sudipta
S
D002563:Cerium / Q000737:chemistry*; D003198:Computer Simulation; D007053:Ice; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D043942:Nanotubes / Q000737:chemistry / Q000648:ultrastructure; D014867:Water / Q000737:chemistry
D007053:Ice; D014867:Water; D002563:Cerium; C030583:ceric oxide