Facile one-pot synthesis of aliphatic thiol-derived nickel nanoclusters used for luminescent and dye degradation applications

Abstract

Nickel nanoclusters (NiNCs) were successfully synthesized via a one-pot method, with 2,3-dimercaptosuccinic acid (DMSA) effectively stabilizing the surface through interaction with Ni. Computational analysis of DMSA was performed using DFT at the B3LYP/3-21G level, confirming structural optimisation and stable geometry. The sulfur (–SH) and carboxyl groups exhibited strong electron-donating and withdrawing tendencies, with HOMO and LUMO values of 0.24915 and 0.18701 respectively, contributing to reactivity and complexation potential. UV–Vis absorption and fluorescence studies confirmed optical activity, with NiNCs displaying strong photoluminescence and a quantum yield of 48 %, attributed to quantum confinement and surface passivation. Cytotoxicity studies revealed over 85 % cell viability up to 100 nM, confirming excellent biocompatibility, while fluorescence microscopy showed minimal morphological alterations. HRTEM analysis indicated well-dispersed NiNCs under 5 nm. Furthermore, NiNCs demonstrated significant dye degradation efficiency within the visible absorbance range (2.3201 × 10⁻³ to 6.0741 × 10⁻⁶ μM), indicating strong photocatalytic potential. Overall, these findings highlight the dual role of aliphatic thiols in stabilizing NiNCs for sustainable both bioimaging and dye degradation applications.