The development of sustainable nanocatalysts is an important challenge in modern chemistry, with the aim of replacing conventional synthesis routes that employ toxic reagents and harsh conditions. In this work, we report the eco-friendly synthesis of AuPd bimetallic nanoparticles, using Alpinia zerumbet extract as a natural reducing and stabilizing agent. 2-Hydroxypropyl-β-cyclodextrin was also used as an additive for the reduction of Pd(II). A detailed characterization confirmed the successful formation of AuPd NPs with a heterogeneous size distribution and the coexistence of small nanoparticles (2–3 nm) along with larger aggregates. The catalytic activity was evaluated in the reduction of nitroaromatic compounds (nitrobenzene, 3-nitroaniline, and 4-nitrophenol) in water, using NaBH4 under mild heating. A maximum turnover frequency (TOF) of 393 h–1 was observed for the reduction of nitrobenzene. The AuPd NPs exhibited enhanced catalytic activity, suggesting a remarkable synergy between the two metals associated with the presence of alloy effects. Overall, these findings highlight the potential of A. zerumbet-mediated AuPd nanoalloys as sustainable and highly efficient nanocatalysts for the detoxification of nitroaromatic pollutants and the production of value-added amines.
Souza et al. (2026) studied this question.