Exploring defect induced fluorescence in borophene dots

Abstract

Borophene dots are emerging as promising zero-dimensional nanomaterials due to their unique structural, electronic, and photophysical properties, particularly their defect-induced fluorescence. This study introduces a novel, scalable synthesis for obtaining fluorescent borophene dots by thermal degradation of sodium borohydride in air. The borophene processing involves controlled heating and intermediate cooling cycles. This route enables incorporating oxygen-related defects as active sites for fluorescence under ambient conditions. Comprehensive characterization techniques, including TEM, AFM, XPS, FTIR, and photoluminescence spectroscopy, reveal that the interplay between boron-hydride and oxygen functional groups modulates the photophysical properties of borophene dots. The findings demonstrate that oxygen-related defects enhance light absorption and emission, with photoluminescence arising from defect-mediated radiative transitions. Defect engineering plays a primary role in tailoring the optical properties of borophene dots, which can be used in optoelectronics, sensing, and bioimaging.