  The compressive strain induced work function modulation in boron nitride
nanosheets (BNNS) has been studied. The compressive strain arose due to the
irradiation of 30 keV Au beam on thin films of BNNS. Before irradiation BNNS
was characterized by Raman spectroscopy, UV-Vis spectroscopy, where using Tauc
plot the bandgap of chemically synthesized BNNS from commercial hBN powder has
been calculated as well as the layer numbers on thin films also quantified
using an empirical relation exploiting the full width at half maxima (FWHM) of
Raman peak of BNNS. The Scanning Electron Microscopy (SEM) images were also
taken where layer like structure in pristine BNNS sample is visible and
irradiation-induced changes in terms of irregular dots on BNNS samples is
witnessed. The X-Ray Diffraction (XRD) was used to characterize the BNNS
samples where peak corresponding to (002) plane is depicted as well as the peak
shifting to higher angle which indicates the compressive strain in BNNS is also
visible. Finally, the possible explanation of compressive strain formation by
Au irradiation on BNNS was discussed using SRIM-2013 MC simulations. We've
explained that vacancy induces strain in materials that lower the work function
(WF). Scanning Kelvin Probe Microscopy (SKPM) was used to map the work function
of the surface of BNNS, and it turned out that WF lowers with increasing dose
of ions. The value of strain also calculated using the work function values and
the results are qualitatively agreeing with the XRD results.
