Paper strips loaded with ultrathin gold nanowires: catalytic activity and stability in the p -nitrophenol reduction

Abstract

Oleylamine-coatedultrathin gold nanowires (AuNWs) were utilized to create catalytic platforms bysimply dropping the colloidal synthesis product onto filter paper strips withoutadditional treatment. These platforms were tested for their ability to catalyzethe reduction of p-nitrophenol (p-NP) to p-aminophenol (p-AP) using sodium borohydride as thereducing agent. Reactions were monitored in a stirred batch recycle reactorwith in situ spectrophotometricmeasurements, and kinetic parameters were analyzed using the Langmuir–Hinshelwood model,taking into account the residence time distribution in the experimental setup.The catalytic activity halted when the catalyst was removed, indicating aheterogeneous process with no leaching. The AuNW platforms showed reusability,successfully operating in over 20 cycles with stable activity after the initial12 cycles. Even after harsh pretreatments, catalytic performance remained acceptable,demonstrating system robustness. The study also examined how operationalconditions like p-NP and NaBH4 concentrations, as well as the number of paper strips,affected performance. The increased exposed area from using multiple stripsenhanced catalytic activity. These results highlight the potential for scalableand robust industrial use of paper-supported ultrathin AuNWs without extensivewashing or pretreatment.