Prediction of Enzyme Class by Using Reactive Motifs Generated from Binding and Catalytic Sites

AbstractThe heterogeneous catalyst HTCMgFe was used in the degradation of the IC, through the heterogeneous photo-fenton treatment, this material in combination with H2O2 and UV light degraded the dye in 30 min at pH 3. As the amount of HTCMgFe increases the degradation it was accelerated because there are more active catalytic sites of Fe2+ on the surface of the material, which generates a greater amount of •OH radicals. The HTCMgFe was characterized by infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray energy dispersive elemental analysis (EDS). The UV-vis spectrum shows that the absorption bands belonging to the chromophore group of the IC disappear as the treatment time passes, indicating the degradation of the dye.

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Nanometer Scale Spectroscopic Visualization of Catalytic Sites During a Hydrogenation Reaction on a Pd/Au Bimetallic Catalyst

10.26434/chemrxiv.12346823.v3 ◽

2020 ◽

Author(s):

hao yin ◽

Liqing Zheng ◽

Wei Fang ◽

Yin-Hung Lai ◽

Nikolaus Porenta ◽

...

Keyword(s):

Catalytic Hydrogenation ◽

Density Functional ◽

Hydrogen Transfer ◽

Bimetallic Catalyst ◽

Local Environment ◽

Hydrogenation Reaction ◽

Boundary Density ◽

Catalytic Sites ◽

Powerful Analytical Tool ◽

Tip Enhanced Raman Spectroscopy

Understanding the mechanism of catalytic hydrogenation at the local environment requires chemical and topographic information involving catalytic sites, active hydrogen species and their spatial distribution. Here, tip-enhanced Raman spectroscopy (TERS) was employed to study the catalytic hydrogenation of chloro-nitrobenzenethiol on a well-defined Pd(sub-monolayer)/Au(111) bimetallic catalyst (pH2=1.5 bar, 298 K), where the surface topography and chemical fingerprint information were simultaneously mapped with nanoscale resolution (≈10 nm). TERS imaging of the surface after catalytic hydrogenation confirms that the reaction occurs beyond the location of Pd sites. The results demonstrate that hydrogen spillover accelerates hydrogenation at the Au sites within 20 nm from the bimetallic Pd/Au boundary. Density functional theory was used to elucidate the thermodynamics of interfacial hydrogen transfer. We demonstrate that TERS as a powerful analytical tool provides a unique approach to spatially investigate the local structure-reactivity relationship in catalysis.

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Nanometer Scale Spectroscopic Visualization of Catalytic Sites During a Hydrogenation Reaction on a Pd/Au Bimetallic Catalyst

10.26434/chemrxiv.12346823.v1 ◽

2020 ◽

Author(s):

Hao Yin ◽

Liqing Zheng ◽

Wei Fang ◽

Yin-Hung Lai ◽

Nikolaus Porenta ◽

...

Keyword(s):

Catalytic Hydrogenation ◽

Density Functional ◽

Hydrogen Transfer ◽

Bimetallic Catalyst ◽

Local Environment ◽

Hydrogenation Reaction ◽

Boundary Density ◽

Catalytic Sites ◽

Powerful Analytical Tool ◽

Tip Enhanced Raman Spectroscopy

Understanding the mechanism of catalytic hydrogenation at the local environment requires chemical and topographic information involving catalytic sites, active hydrogen species and their spatial distribution. Here, tip-enhanced Raman spectroscopy (TERS) was employed to study the catalytic hydrogenation of chloro-nitrobenzenethiol on a well-defined Pd(sub-monolayer)/Au(111) bimetallic catalyst (pH2=1.5 bar, 298 K), where the surface topography and chemical fingerprint information were simultaneously mapped with nanoscale resolution (≈10 nm). TERS imaging of the surface after catalytic hydrogenation confirms that the reaction occurs beyond the location of Pd sites. The results demonstrate that hydrogen spillover accelerates hydrogenation at the Au sites within 20 nm from the bimetallic Pd/Au boundary. Density functional theory was used to elucidate the thermodynamics of interfacial hydrogen transfer. We demonstrate that TERS as a powerful analytical tool provides a unique approach to spatially investigate the local structure-reactivity relationship in catalysis.

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Dissolution and Performing Homogeneous Photocatalysis of Polymeric Carbon Nitride

10.26434/chemrxiv.6959627 ◽

2018 ◽

Author(s):

Chaofeng Huang ◽

Jing Wen ◽

Yanfei Shen ◽

Fei He ◽

Li Mi ◽

...

Keyword(s):

Conjugated Polymer ◽

Carbon Nitride ◽

Heterogeneous Catalysts ◽

Methane Sulfonic Acid ◽

Environment Friendly ◽

The Poor ◽

Catalytic Sites ◽

Homogeneous Photocatalysis ◽

Polymeric Carbon ◽

First Time

<a></a><a>As a metal-free conjugated polymer, carbon nitride (CN) has attracted tremendous attention as heterogeneous (photo)catalysts. </a><a></a><a>By following prototype of enzymes, making all catalytic sites of accessible via homogeneous reactions is a promising approach toward maximizing CN activity, but hindered due to </a><a></a><a>the poor insolubility of CN</a>. Herein, we report the dissolution of CN in environment-friendly methane sulfonic acid and the homogeneous photocatalysis driven by CN for the first time with the activity boosted up to 10-times, comparing to the heterogeneous counterparts. Moreover, facile recycling and reusability, the <a>hallmark</a> of heterogeneous catalysts, were kept for the homogeneous CN photocatalyst via reversible precipitation using poor solvents. It opens new vista of CN in homogeneous catalysis and offers a successful example of polymeric catalysts in bridging gaps of homo/heterogeneous catalysis.

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