Abstract:
With the use of the Langmuir–Blodgett (LB) method on the KSV NIMA 2002 plant, ferro-electric films of the stabilized barium titanate (ST BTO) from colloidal system of sodium oleate aqueous solution have been produced, which were studied with small angle X-ray scattering and dynamic light scattering techniques. Coagulants with the most characteristic hydrodynamic diameter $\sim$200 nm are found and the physical model of their formation from barium titanate nanoparticles ($\sim$20 nm) in this colloidal system is proposed. By means of compression-expansion isotherms with the use of a MicroBAM micro-scope and the device for measurement of surface potential SPOT, optimum parameters of sedimentation are determined, which made it possible to produce uniform ferroelectric films with ST BTO particles of $\sim$20 nm in size and a forbidden band width of 3.6 eV. With scanning probe and electron microscopy, vibrational and X-ray photoelectron spectroscopy, and also X-ray diffractometry, topological and structural features and distri-bution of chemical elements in the produced films on different substrates have been stud-ied.
Keywords:barium titanate, langmuir films, coagulation mechanism, crystal structure, band gap.