Preparation of size-controlled Pt supported on Al2O3 nanocatalysts for deep catalytic oxidation of benzene at lower temperature

A series of Pt/Al2O3 catalysts possessing controlled Pt particle sizes (1.2–2.2 nm) could be single-step synthesized by means of modified ethylene glycol (EG) reduction approach. Their catalytic activities were evaluated for the catalytic complete oxidation of benzene, as typical volatile organic compounds (VOCs). The results showed that Pt/Al2O3 catalyst with 1.2 nm Pt size exhibited optimum catalytic oxidation activity of benzene at 145 °C. It has been confirmed that the content of Pt0 species, which is regarded as active center for complete oxidation of benzene, is not the decisive factor in the process of benzene oxidation. The structure sensitivity was explained by the surface adsorbed oxygen. The electron transportation from Pt to O is in favour of the activation of adsorbed oxygen, which is beneficial to enhance catalytic activity. Moreover, the catalysts showed excellent adaptability for different VOCs and durability for benzene oxidation during the long-term continuous test, whether in dry air or in the coexistence of CO2, cyclohexane or H2O.