Morphology dependence of Nb2O5-supported cobalt oxide in catalytic toluene oxidation†
Abstract
This research describes the preparation of cobalt-based catalysts supported on Nb2O5 substrates of various forms: rods (Nb2O5-R), grids (Nb2O5-G), and spherical structures (Nb2O5-S). These catalysts demonstrated diverse reactivity in toluene oxidation, which correlated with their individual physical and chemical traits and the interfacial interaction between cobalt oxide and the Nb2O5 support. Notably, the catalyst with a spherical Nb2O5 support (CoOx/Nb2O5-S) outperformed the catalysts with other supports and showed the best activity in oxidizing toluene. The investigation underscored the role of the unique features of the Nb2O5 substrate in augmenting the catalyst's efficacy in toluene adsorption and activation. Density functional theory (DFT) revealed more facile toluene adsorption on CoOx/Nb2O5-S (−0.65 eV) and reduced energy requirements for oxygen vacancy creation and adsorption. This suggested that the CoOx/Nb2O5-S catalyst enhanced surface oxygen mobility and boosted catalytic efficiency.
- This article is part of the themed collection: Emerging Investigator Series