Related Experiment Video
Updated: Dec 3, 2025
09:05
Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
15.2K
Defect Engineering on Boron Nitride for O2 Activation and Subsequent Oxidative Desulfurization
Summary
Atomically doping hexagonal boron nitride (h-BN) with impurities like oxygen and carbon enhances its catalytic activity for aerobic reactions. Specifically, ON and C-doped h-BN show promise for oxidative desulfurization, particularly for dibenzothiophene.
Area of Science:
- Materials Science
- Catalysis
- Computational Chemistry
Background:
- Hexagonal boron nitride (h-BN) is a promising material for catalysis, but its intrinsic activity for aerobic reactions is limited.
- Atomic-level modification of h-BN is crucial for designing highly active catalysts.
- Doping with impurity atoms offers a strategy to enhance catalytic properties.
Purpose of the Study:
- To investigate the effect of atomic-level doping on the catalytic activity of h-BN for aerobic reactions.
- To explore the potential of doped h-BN in oxidative desulfurization (ODS) processes.
Main Methods:
- Density functional theory (DFT) calculations were employed to construct and study various doping systems in h-BN.
- The activation of molecular oxygen (O2) on different defect sites (O, C impurities, B, N antisites) was analyzed.
- The performance of selected doped h-BN systems in oxidative desulfurization of sulfocompounds was evaluated.
Main Results:
- Oxygen (ON) and Boron antisite (BN) defects significantly enhance O2 activation.
- Carbon impurities (CB, CN) moderately activate O2, while Nitrogen antisite (NB) and Oxygen antisite (OB) defects lead to unstable intermediates.
- ON and C-doped h-BN systems demonstrated excellent performance in the oxidative desulfurization of dibenzothiophene (DBT).
Conclusions:
- Atomic doping, particularly with oxygen and carbon, is an effective strategy to rationally design highly active h-BN catalysts.
- ON and C-doped h-BN are suitable candidates for aerobic oxidative desulfurization reactions.
- The BN antisite is not ideal for aerobic reactions due to the formation of stable B-O-B species.
More Related Videos
Related Concept Videos
03:08Hydroboration-Oxidation of Alkenes
10.4K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
10.4K
02:36Regioselectivity and Stereochemistry of Hydroboration
9.2K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
9.2K
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
20.1K
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
20.1K
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
12.1K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
12.1K