Abstract
Gold nanoparticles with different shapes were prepared and used as catalysts in the reduction of p-nitrophenol (PNP) in the aqueous phase and in the presence of sodium borohydride (NaBH4). Parameters such as the reaction temperature, substrate/NaBH4 molar ratio, and substrate/gold molar ratio were tested and evaluated. In this paper, we compare the catalytic reactivities of gold nanorods (AuNRs) and gold nanospheres (AuNSs), both synthesized by the seed-mediated method in the presence of cetyltrimethyl ammonium bromide (CTAB). Physical-chemical parameters such as the apparent rate constant (kapp) and activation energy (Ea) of the reactions were obtained for both systems. We observed that the catalytic system based on AuNRs is the most active. These colloidal dispersions were investigated and fully characterized by ultraviolet-visible absorption spectroscopy (UV–Vis) and transmission electron microscopy (TEM).
Highlights
The study and development of new soluble nanocatalysts in water has attracted the attention of several research groups in recent years
As we adopted seed‐mediated method to prepare the AuNPs for both colloidal systems, it is expected that the the seed-mediated method to prepare the AuNPs for both colloidal systems, it is expected that the number of AuNPs in both catalytic systems is the same, as well as the total number of gold atoms
We have demonstrated that aqueous colloidal solutions based on soluble AuNPs with different morphologies—gold nanorodsnanorods (AuNRs) or
Summary
The study and development of new soluble nanocatalysts in water has attracted the attention of several research groups in recent years. Due to their large surface/volume ratio, nanoparticulated catalytic materials can be considered as better catalysts than their bulky form counterparts [1,2]. Economic and ecological priorities have pressed the scientific community to develop highly active catalytic systems in water for different reactions [3]. In its bulky forms, metallic gold presents low reactivity and has been overlooked for many years as a potential catalyst. It was more recently verified that gold nanoparticles are quite active catalysts for many reactions, such as chemical reductions and oxidations [5]. Hydrogenation reactions are the most common reactions that have been conducted using colloidal or supported transition metal nanoparticles
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
