Title:Modified Layered Nanohybrid Structures for the Slow Release of Urea
VOLUME: 4 ISSUE: 2
Author(s):Nilwala Kottegoda, Chanaka Sandaruwan, Piyumi Perera, Nadeesh Madusanka and Veranja Karunaratne
Affiliation:Sri Lanka Institute of Nanotechnology (SLINTEC), Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Center for Excellence in Nanotechnology, Mahenwatta, Pitipana, Homagama, Sri Lanka.
Keywords:Layered double hydoxide, montmorillonite, nanoclays, nanohybrid, slow release, urea.
Abstract:Urea intercalated layered material nanohybrid formulations based on two types of layered
clays, layered double hydroxides and montmorillonite were developed for agricultural applications
as slow release nitrogen plant nutrient formulations. The resulting nanohybrids were prepared by the
intercalation of urea between the nanolayers of clay matrixes. The successful intercalation of the
guest urea molecule was confirmed using the number of solid state characterization techniques and
the possible structure of urea between the layers was deduced. Urea molecules are expected to be bound through their
carbonyl and amine modes to the nanolayers of the clay with several interaction modes of different bond strengths. Thus,
electrostatic interactions between urea and the nanoclay layers would reduce the rate of hydrolysis of urea and
decomposition into gaseous products. Release behavior of urea of nanohybrids was studied in water and compared with
that of pure urea. Both nanohybrid formulations displayed significant degree of slow release behavior.
