The Synthesis of Pt-CNTs Nanocatalyst Promoted by Visible Light and Catalytic Reduction of 4-Nitrophenol

Abstract

Photochemistry to prepare platinum nanoparticles (Pt NPs) is an essential way to control Pt NPs catalyst size distribution. This article reports a series of morphologically controlled syntheses of Pt NPs loaded on modified carbon nanotube (Pt-CNTs). In the synthesis, Polyethylene glycol (PEG) participates in reactions both as a reducing agent and a stabilizer. Visible light irradiation was adopted as a kinetic controlling approach. Typical 4-nitrophenol (4-NP) reduction was adopted to probe the catalytic performances. Characterizations prove that visible light irradiation is an effective way to control the reaction process. In the optimized reaction conditions, i.e., when the ratio PEG:H2O is 1:9, and the pH is 10, the as-prepared Pt NPs are consequently in a very narrow sized distribution with an average diameter of 1.29 nm. The Pt-CNTs present a high reaction rate constant of 0.624 min-1 in the catalytic reduction of 4-NP. All the research results are beneficial for exploring more green chemistry and facile photochemical approaches in the controlled preparation of Pt nanocatalysts.