Pt–Pd bimetallic nanoparticles anchored on uniform mesoporous MnO2 sphere as an advanced nanocatalyst for highly efficient toluene oxidation

Abstract

Improving catalytic performance is a yet still challenge in thermal catalytic oxidation. Herein, uniform mesoporous MnO2 nanosphere-supported bimetallic Pt–Pd nanoparticles were successfully fabricated via a SiO2 template strategy for the total catalytic degradation of volatile organic compounds at low temperature. The introduction of mesopores into the MnO2 support induces a large specific surface area and pore size, thus providing numerous accessible active sites and enhanced diffusion properties. Moreover, the addition of a secondary noble metal can adjust the Oads/Olatt molar ratios, resulting in high catalytic activity. Among them, the catalyst having a Pt/Pd molar ratio of 7:3 exhibits optimized catalytic activity at a weight hourly space velocity of 36,000 mL g−1 h−1, reaching 100% toluene oxidation at 175 °C with a lower activation energy (57.0 kJ mol−1) than the corresponding monometallic Pt or non-Pt-based catalysts (93.8 kJ mol−1 and 214.2 kJ mol−1). Our findings demonstrate that the uniform mesoporous MnO2 nanosphere-supported bimetallic Pt–Pd nanoparticles catalyst is an effective candidate for application in elimination of toluene.

Keywords

• MnO2 nanospheres
• Mesoporous structure
• Pt–Pd bimetal
• VOCs oxidation