A facile one-pot synthesis of blue and red luminescent thiol stabilized gold nanoclusters: a thorough optical and microscopy study

Abstract

Here in this contribution, blue and red luminescent 1-dodecanethiol (DT) terminated gold nanoclusters (AuNC) were prepared by a simple two-step synthesis route where the first step involved the surfactant-free synthesis of bare AuNC in N,N′-dimethylformamide (DMF) and the second step is the termination of the as-prepared bare AuNC by 1-dodecanethiol. The blue and red luminescent DT-terminated AuNC were isolated by a solvent-induced precipitation followed by an ultra-centrifugation technique. Both the bare AuNC and the blue and red luminescent DT-terminated AuNC exhibit stable photoluminescence and good solubility in various solvents. The photo-physical, electronic, structural, and morphological properties of the bare AuNC and the blue and red luminescent DT-terminated AuNC were examined by performing UV-Vis absorption spectroscopy, stationary and time-resolved PL spectroscopy, X-ray photoelectron spectroscopy (XPS), femtosecond transient absorption spectroscopy, Fourier-transform infrared spectroscopy (FTIR-ATR), and high-resolution transmission electron microscopy (HRTEM) experiments.