Nanocage‐Shaped Co_3−xZr_xO₄ Solid‐Solution Supports Loaded with Pt Nanoparticles as Effective Catalysts for the Enhancement of Toluene Oxidation

Abstract

Nanocage‐shaped Co3−xZrxO4 solid‐solution supports and the corresponding platinum loaded nanocomposites, yPt/Co3−xZrxO4 (x =0.27, 0.50, 0.69; y = 0.5, 1.0, 2.0 wt.%), are successfully fabricated via a Cu2O nanocube hard template method and a glycol reduction method, respectively. The hollow nanocage structures obviously improve surface areas; moreover, the Zr doping forms the Co3−xZrxO4 solid‐solution supports, and the corresponding yPt/Co3−xZrxO4 catalysts promote the enhancement of catalytic performance. Catalytic activity toward toluene combustion is enhanced for the 2.0 wt% Pt/Co2.73Zr0.27O4 catalyst. The catalysts are characterized using multiple techniques. Pt nanoparticles are uniformly dispersed across the Co2.73Zr0.27O4 nanocage surface. The 2.0 wt% Pt/Co2.73Zr0.27O4 catalyst exhibits the highest catalytic activity among all the samples and demonstrates good stability, with 90% toluene conversion obtained at a temperature of 165 °C. The same catalyst accomplishes full toluene oxidation at 180 °C, at a weight hourly space velocity of 36 000 mL h−1 g−1. The apparent activation energy (Ea) over the yPt/Co2.73Zr0.27O4 samples are significantly lower than those over the Co3−xZrxO4 supports, with the 2.0 wt% Pt/Co2.73Zr0.27O4 catalyst exhibiting the lowest Ea value. These findings demonstrate the potential of the 2.0 wt% Pt/Co2.73Zr0.27O4 catalyst as a promising catalyst toward atmospheric toluene removal.

A Novel Green Process for Recovery of Transition Metal Ions from Used Lithium-ion Batteries by Selective Coordination of Ethanol

“…X-ray photoelectron spectroscopy was employed to detect valence changes of metal ions (Thermo Scientific, USA). All binding energies were calibrated using the C 1s peak at 284.8 eV …”

“…All binding energies were calibrated using the C 1s peak at 284.8 eV. 40 ■ RESULTS AND DISCUSSION Characterization of DES. Structures of lactic acid, betaine hydrochloride, and prepared DES as well as the preparation process are shown in Figures 2a, b.…”

Molecular synergistic synthesis of AIPO‐18 zeolite‐stabilized Pt nanocatalysts with high dispersion for the hydrogenation of levulinic acid to γ‐valerolactone

“…However, the high intrinsic surface energy of metallic platinum puts pressure on maintaining its original structure and properties, and agglomeration of platinum during the reaction favors directing rapid deactivation of functional catalysts. [1][2][3][4][5] Stemming from this, various approaches have been tried to improve the dispersion and resistance to sintering of metallic platinum substances.…”

Modulating Adsorption–Redox Sites and Charge Separation of Cs3Bi2Br9–x@AgBr Core–Shell Heterostructure for Selective Toluene Photooxidation

“…Especially, in photocatalytic toluene oxidation using O 2 as an oxidant, the introduction of vacancies can strengthen the adsorption of inert toluene . But, on the other hand, it may bring about competitive adsorption of O 2 at the defect site because the O 2 molecule has smaller steric hindrance and stronger electron affinity. , Moreover, the defect sites usually serve as the trapping centers of photogenerated electrons (e – ) or holes (h + ) for redox reactions. , The competitive adsorption at the vacancy sites will naturally lead to confusion between the adsorption site and reactive center of reactants (e.g., electron-driven reduction of O 2 and hole-driven oxidation of toluene) in heterojunction systems, thereby resulting in mismatched redox kinetics and undesirable photocatalytic activity.…”