Construction of Nanoreactors Combining Two-Dimensional Hexagonal Boron Nitride (h-BN) Coating with Pt/Al₂O₃ Catalyst toward Efficient Catalysis for CO Oxidation

Abstract

In this work, a nanoreactor combining layers of facile traditional two-dimensional (2D) material, hexagonal boron nitride (h-BN, which often called the white graphene) with Pt/Al 2 O 3 catalyst was designed to exhibit higher stability, activity, and selectivity in automobile exhaust treatment. Characterization revealed that h-BN does coat on the surface of platinum and forms a distinct Pt@h-BN/Al 2 O 3 core−shell nanostructure. This as-prepared catalyst possesses good thermal stability and selectivity, because of the excellent high-temperature tolerance and the multidefected structure of the h-BN shell; that is, small molecules such as CO and O 2 can easily intercalate into the nanoreactor, while large molecules such as propylene are blocked out. Meanwhile, the intercalated reactants can achieve the conversion of CO to CO 2 faster (ΔT 100 = 20 °C) with the confinement effect. The study indicates that constructing a nanoscale confined environment with two-dimensional (2D) coating can enhance the performance of the catalyst in multiple aspects and simultaneously provide a good example for designing nanostructured catalysts with multifaceted improvement.

Revealing the Sudden Alternation in Pt@h‐BN Nanoreactors for Nearly 100% CO2‐to‐CH4 Photoreduction

“…As the temperature rises, the IS-AB will be more around the Pt particles at the second-stage dehydrogenation process. [34][35][36] When the temperature reaches 700 °C, the third-stage dehydrogenation will be completed under NH 4 OH atmosphere, and IS-AB will be completely cross-linked into 2D h-BN coatings. The number of coating layers can be adjusted by changing the molar ratio of Pt to NH 3 BH 3 and this article involves 1-10 layers.…”

Environmental Applications of Engineered Materials with Nanoconfinement

“…Heterogeneous redox reactions for the degradation of organic contaminants have frequently been explored using functional nanoporous materials that accelerate the catalytic process via nanoconfinement effects, either as a host redox mediator − or reaction reservoirs. ,, Some conductive porous catalysts with spatial confinement effects can lower the required energy barriers for oxidation or reduction reactions. , Therein, nanoconfinement modulates the electron properties at the catalyst surface to enhance either the accumulation of polar reactants or the electron transfer during redox processes. This improvement can be epitomized in a first-principle study using a carbon nanotube reactor, where SO 2 -to-SO 3 oxidation was enhanced by an increase in electron density that was modulated by the nanotube curvature .…”

Integration of Polydopamine and Fe3O4 Nanoparticles with Graphene Oxide to Fabricate an Efficient Recoverable Catalyst for the Degradation of Sulfadiazine

“…Figure b shows the FT-IR spectra of M-GO–PDA, in which the peaks at 474 and 555 cm –1 indicated the stretching and bending bands of Fe–O–Fe, respectively . The CO (1645 cm –1 ) and C–N (1126 cm –1 ) vibration peaks also existed. , For all three samples, the peaks located at 3439 and 1651 cm –1 were related to the O–H and H–O–H vibrations . Finally, the peaks observed from 2845 to 2950 cm –1 were caused by the C–H bond vibration …”

“…31 The CO (1645 cm −1 ) and C−N (1126 cm −1 ) vibration peaks also existed. 32,33 For all three samples, the peaks located at 3439 34 Finally, the peaks observed from 2845 to 2950 cm −1 were caused by the C−H bond vibration. 35 N 2 adsorption−desorption isotherms for the prepared samples are shown in Figure 1c.…”