Nanocomposites and nanomaterials

Preparation and studying of Langmuir films based on N-doped graphene oxide
Ibrayev N., Seliverstova E., Dzhanabekova R., Zhumabekov A.
Institute of Molecular Nanophotonics, Buketov KarSU, Universitetskaya str. 28, Karaganda 100028, Kazakhstan.
E-mail: niazibrayev@mail.ru, evgnseliverstova@gmail.com

Conditions for the preparation of stable graphene films based on N-doped graphene oxide (NGO) were studied. NGO dispersions (N-doped graphene oxide, SigmaAldrich) in water-DMF were used.
The physico-chemical properties of NGO monolayers, formed from dispersions in water-DMF, at the surface of water-air interface were studied. The transfer of monolayers to a solid substrate was carried out by a vertical method using the KSV NIMA Langmuir-Blodgett system at different surface pressures of: 5, 8, 10, 35 mN/m. SEM measurements showed that the NGO forms island films with an area of several mm. In the structure of films that were transferred at low surface pressures it is possible to distinguish multilayer structures formed by the overlapping of individual sheets of NGO. The total area of the substrate coated with a film was varied from 70 to 93% for films obtained at different values of π.

a	b	c	
SEM-images of NGO LB films, transferred at various surface pressures, mN/m: a – 5; b – 10; c – 20 

When studying the optical properties of NGO LB films, the absorption spectrum with a maximum of about 250 nm and the shoulder at 300 nm, characteristic for graphene oxide, was recorded. The synthesized NGO films have a high transparency in the visible range of the spectrum – from 80 to 90%, which makes them attractive for various technological applications.