The Preparation and Catalytic Properties of Nanoporous Pt/CeO2 Composites with Nanorod Framework Structures

Abstract

Pt/CeO2 catalysts with nanoporous structures were prepared by the facile dealloying of melt-spun Al92−XCe8PtX (X = 0.1; 0.3 and 0.5) ribbons followed by calcination. The phase compositions and structural parameters of the catalysts were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). The specific surface area and pore size distribution were characterized by N2 adsorption–desorption tests. The catalytic properties were evaluated by a three-way catalyst (TWC) measurement system. The results revealed that the dealloyed samples exhibited a nanorod framework structure. The Pt nanoparticles that formed in situ were supported and highly dispersed on the CeO2 nanorod surface and had sizes in the range of 2–5 nm. For the catalyst prepared from the melt-spun Al91.7Ce8Pt0.3 ribbons, the 50% CO conversion temperature (T50) was 91 °C, and total CO could be converted when the temperature was increased to 113 °C. An X-ray photoelectron spectroscopy (XPS) test showed that the Pt0.3/CeO2 sample had a slightly richer oxygen vacancy; and a H2 temperature-programmed reduction (H2-TPR) test demonstrated its superior adsorption ability for reduction gas and high content of active oxygen species. The experiments indicated that the catalytic performance could be retained without any attenuation after 130 h when water and CO2 were present in the reaction gas. The favorable catalytic activities were attributed to the high specific areas and small pore and Pt particle sizes as well as the strong interactions between the CeO2 and Pt nanoparticles. The Pt nanoparticles were embedded in the surface of the CeO2 nanorods, inhibiting growth. Therefore, the catalytic stability and water resistance were excellent.

Dealloying Synthesis of Bimetallic (Au–Pd)/CeO2 Catalysts for CO Oxidation

“…Dealloying is a simple, efficient, and environmentally friendly technique to fabricate nanoporous materials on a large scale. − The pore size and surface structure of materials can be controlled by regulating the corrosion temperature, reaction rate, and composition of alloys. , Transition metal oxides (NiO, CuO, Co 3 O 4 ) and noble metals (Ag, Rh, , Pt) have been reported to support the CeO 2 nanorod successfully . The obtained CeO 2 -based catalysts display outstanding catalytic activity.…”

Reverse Microemulsion Synthesis of Mesopore Phloroglucinol‐Resorcinol‐Formaldehyde Carbon Aerogel Microsphere as Nano‐Platinum Catalyst Support for ORR

“…However, the slow kinetics of the oxygen reduction reaction (ORR) at the cathode greatly limits the advancement and widespread adoption of metal‐air battery . Pt‐based catalysts have been regarded as the essential materials in electrocatalyst for ORR, and currently the most research concentration is focusing on introducing secondary transition metals through the formation of Pt alloy (PtNi, PtCo, PtCu or PtPb) catalysts to improve the electrocatalytic activity of Pt‐based catalysts . However, choosing suitable material as Pt‐based catalyst support is an effective method for enhancing the electrocatalytic activity of Pt‐based catalysts, such as carbon nanotube, graphene, carbon aerogel.…”