Hydroxyl-Decorated Pt as a Robust Water-Resistant Catalyst for Catalytic Benzene Oxidation

Abstract

In catalytic oxidation reactions, the presence of environmental water poses challenges to the performance of Pt catalysts. This study aims to overcome this challenge by introducing hydroxyl groups onto the surface of Pt catalysts using the pyrolysis reduction method. Two silica supports were employed to investigate the impact of hydroxyl groups: SiO2–OH with hydroxyl groups and SiO2–C without hydroxyl groups. Structural characterization confirmed the presence of Pt–O x , Pt–OH x , and Pt0 species in the Pt/SiO2–OH catalysts, while only Pt–O x and Pt0 species were observed in the Pt/SiO2–C catalysts. Catalytic performance tests demonstrated the remarkable capacity of the 0.5 wt % Pt/SiO2–OH catalyst, achieving complete conversion of benzene at 160 °C under a high space velocity of 60,000 h–1. Notably, the catalytic oxidation capacity of the Pt/SiO2–OH catalyst remained largely unaffected even in the presence of 10 vol % water vapor. Moreover, the catalyst exhibited exceptional recyclability and stability, maintaining its performance over 16 repeated cycles and a continuous operation time of 70 h. Theoretical calculations revealed that the construction of Pt–OH x sites on the catalyst surface was beneficial for modulating the d-band structure, which in turn enhanced the adsorption and activation of reactants. This finding highlights the efficacy of decorating the Pt surface with hydroxyl groups as an effective strategy for improving the water resistance, catalytic activity, and long-term stability of Pt catalysts.

Weakening Mn–O Bond Strength in Mn-Based Perovskite Catalysts to Enhance Propane Catalytic Combustion

“…Catalytic combustion (oxidation) has been widely regarded as one of the most promising ways to eliminate VOC emissions due to its low cost and high efficiency. , The core of this technology lies in the development of catalysts that convert harmful VOCs into harmless CO 2 and H 2 O, which can exhibit remarkable activity at low temperatures and exceptional thermal stability at high temperatures. , Although noble metal-based ( e.g. , Pt and Pd) catalysts have high catalytic activity for VOC oxidation, − the high cost poses a significant barrier to widespread implementation, which has prompted researchers to focus on developing low-cost transition metal oxide catalysts. − …”