Coaxially Electrospun 1D TiO2/Au x ( X = 2.5, 5.0, 7.5) Heterojunction Nanofibers: Unveiling the Role of TiO2–Au x

Abstract

A “silent killer” that threatens aerobic life, carbon monoxide (CO) pollution has increased due to the Earth’s ecological equilibrium being upset by rapid industrialization and excessive resource extraction. In this study, titanium dioxide nanofibers (TiO2) decorated with gold nanoparticles (AuNPs@TiO2) were synthesized using a direct coaxial electrospinning technique, which eliminates the need for presynthesized AuNPs. The resulting AuNPs@TiO2 were evaluated for their catalytic performance in rapid CO oxidation. Catalytic activity was investigated for varying Au concentrations (2.5, 5.0, and 7.5 mM) incorporated into the TiO2 framework. The catalytic performance of TiO2–Aux nanofibers varied with Au loading, with conversion efficiencies following the trend: TiO2/Au0 (673 K)<TiO2/Au5.0 (673 K)<TiO2/Au7.5 (623 K)<TiO2/Au2.5 (673 K). With its enhanced activity, Au2.5@TiO2 proves that the TiO2–Au interfacial contact is optimized at an ideal Au concentration, allowing for efficient charge transfer and oxygen activation. This study demonstrates a heterojunction-engineering strategy for developing a highly efficient catalytic CO oxidation, achieved through precise modulation of the TiO2–Au interfacial synergy to enhance electron transport and oxygen activation. This proposed approach aims to produce TiO2/Au for catalytic CO oxidation via coaxial electrospinning. It will provide insight into how designing the metal-oxide interface increases the kinetics of oxidation.