Au–Pt bimetallic nanoparticles supported on nest-like MnO2: synthesis and application in HCHO decomposition

Abstract

Facile synthesis of Au–Pt bimetallic nanoparticles (Au1−x Pt x NPs) and mixtures of Au NPs and Pt NPs ((100 % − y)Au/yPt NPs) and their subsequent deposition on nest-like MnO2 nanostructures were presented. The as-prepared products were characterized by means of UV–visible spectroscopy, X-ray diffraction, scanning and transmission electron microscopy, and energy dispersive spectroscopy. TEM analyses showed that noble metal NPs were evenly dispersed on the surface of nest-like MnO2 nanostructures and no agglomeration was observed. The as-prepared metal NPs supported catalysts showed higher catalytic activities than MnO2 nanostructures for oxidative decomposition of formaldehyde (HCHO). The forms of noble metal NPs and Au/Pt molar ratio have significant effects on the catalytic performance, and Au0.5Pt0.5/MnO2 has the highest catalytic activity among all the as-prepared metal NPs supported MnO2 catalysts, and the temperature for complete decomposition of HCHO reached as low as 313 K. The high catalytic activities of Au1−x Pt x /MnO2 catalysts resulted from the synergistic effect between Au1−x Pt x NPs and MnO2 nanostructure, as well as the synergistic effect between Au and Pt. The current Au1−x Pt x /MnO2 catalysts are among the first trials to apply bimetallic NP-supported catalysts to the decomposition of HCHO, and proved that the Au1−x Pt x /MnO2 catalysts are promising for indoor decomposition of formaldehyde due to their easy synthesis, low cost, and excellent catalytic performance.