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Ikea cellulose, in this case it may indicate that the GO flakes are
arranged in a direction perpendicular to the cellulose chain.
The HBI parameter is unchanged for all samples, which
indicates that no hydrogen bonds have been formed after

the GO layer has been applied.
The surface modification was carried out at 22/28 deg C,
so these were mild conditions for the pine substrate (control
sample). Such deposition methods may not affect the surface
significantly. The TCI parameter increased after GO deposition,
but since the IR beam penetrates the surface at 5–15 µm in
depth, the change is strictly local.

Conclusions of the Research

This study used the LIBS method to identify mainly carbon
and oxygen in wood impregnated with graphene oxide. The
cm−1 which is associated with the β-glycosidic bond, assigned method used enabled us to characterise differences in the
to the C-O-C stretching vibrations. signal intensity originating from the elements depending on
The 1430 cm−1 band, associated with the symmetric -CH2 the wood impregnation method.
bending vibrations, is associated with the crystalline part of A higher intensity of the signal originating from carbon
cellulose. The decrease in the band intensity is corelated with and oxygen was identified in the near-surface layers in the

the decrease in cellulose crystallinity. early wood cell zone. The low intensity of the signals of the
The spectrum of examined samples shows characteristic tested elements on the surface of wood impregnated using
peaks for cellulose compounds. The range of 3200–3500 cm−1 the pressureless ultrasound method may indicate disintegration
corresponds to -OH stretching vibrations, the bands around processes occurring in the near-surface cell structures of wood.
2930–2840 cm−1 are related to C-H stretching vibrations, and Despite the low signal intensities recorded in the LIBS
the peaks 1732, 1638, 1420, and 1370 cm−1 are related to the study for wood impregnated using the pressureless method,
presence of C = O stretching, -OH bending, C-OH stretching a slight increase in absorbance was noted in the range of
and C-H bending bonds, respectively. 2500–3600 cm−1 in the FTIR studies.
The peaks 1154 and 1055 cm−1 are related to the cellulose It can be assumed that these changes result from the

skeleton in the form of C-O-C and C-O bonds. No new peaks GO layer deposition on the wood surface (the effect of the
are observed after GO is introduced to the surface of the -OH and -CH2 groups). Microscopic examinations indicate
control sample for both variants (GO and GOU). the presence of graphene oxide flakes in the cells of the
A slight increase in absorbance was recorded for the GOU surface layers of wood.
sample in the area of 2500–3600 cm−1. Due to the lack of Based on the studies, the LIBS technique correlated with
changes in other areas, it can be assumed that these changes the FTIR method can be used to identify changes occurring in
are the results of GO layer deposition on the wood surface the surface layers of wood subjected to various impregnation

(influence of -OH and -CH2 groups). methods. FDM
The LOI parameter represents the regions ordered in the ENQUIRY NO. 1101