  Single photon emitters (SPEs) are a key component for their use as pure
photon source in quantum technologies. In this study, we investigate the
generation of SPEs from drop-casted hexagonal boron nitride (hBN) nanoflakes,
examining the influence of the immersion solution and the source of hBN. We
show that, depending on the utilized supplier and solution the number and
quality of the emitters changes. We perform a comprehensive optical
characterization of the deposited nanoflakes to assess the quality of the
generated SPEs. We show quantitative data on SPE yields, highlighting
significant variations among solvents and different sources of hBN. This holds
particular significance for employing drop-casted nanoflakes as SPE sources in
quantum communication, sensing, and imaging. Our method is easily expandable to
all kinds of surfaces and can be done without requiring complex fabrication
steps and equipment, thus providing the necessary scalability required for
industrial quantum applications.
