Metal-organic layers as reusable solid fluorination reagents and heterogeneous catalysts for aromatic fluorination

Abstract Metal-organic layers (MOLs) with ordered structure and molecular tunability are of great potential as heterogeneous catalysts due to their readily accessible active sites. Herein, we demonstrate a facile template strategy to prepare MOLs with a uniform thickness of three metal coordination layers (ca. 1.5 nm) with graphene oxide (GO) as both template and electron mediator. The resulting MOL@GO exhibits an outstanding performance for CO2 photoreduction with a record-high total CO yield of 3133 mmol/gMOL among all the metal-organic framework and MOL catalysts (CO selectivity of 95%). This performance is ca. 34 times higher than that of bulky Co-MOF, [CoL(H2O)2]•0.5H2O (H2L = 5-(1H-1,2,4-triazol-1-yl)isophthalic acid). Systematic studies reveal that well exposed active sites in MOLs, and facile electron transfer between heterogeneous and homogeneous components mediated by GO, greatly contribute to its high activity. This work highlights a facile way for constructing ultrathin MOLs and demonstrate charge transfer pathway between conductive template and catalyst for boosting photocatalysis.

Download Full-text

Facile electron delivery from graphene template to ultrathin metal-organic layers for boosting CO2 photoreduction

Nature Communications ◽

10.1038/s41467-021-21084-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jia-Wei Wang ◽

Li-Zhen Qiao ◽

Hao-Dong Nie ◽

Hai-Hua Huang ◽

Yi Li ◽

...

Keyword(s):

Graphene Oxide ◽

Active Sites ◽

Heterogeneous Catalysts ◽

Metal Organic Framework ◽

Ordered Structure ◽

Uniform Thickness ◽

Excellent Performance ◽

Electron Mediator ◽

Organic Layers ◽

Metal Organic

AbstractMetal-organic layers with ordered structure and molecular tunability are of great potential as heterogeneous catalysts due to their readily accessible active sites. Herein, we demonstrate a facile template strategy to prepare metal-organic layers with a uniform thickness of three metal coordination layers (ca. 1.5 nm) with graphene oxide as both template and electron mediator. The resulting hybrid catalyst exhibits an excellent performance for CO2 photoreduction with a total CO yield of 3133 mmol g–1MOL (CO selectivity of 95%), ca. 34 times higher than that of bulky Co-based metal-organic framework. Systematic studies reveal that well-exposed active sites in metal-organic layers, and facile electron transfer between heterogeneous and homogeneous components mediated by graphene oxide, greatly contribute to its high activity. This work highlights a facile way for constructing ultrathin metal-organic layers and demonstrates charge transfer pathway between conductive template and catalyst for boosting photocatalysis.

Download Full-text

An Overview of Metal-organic Frameworks-based Acid/Base Catalysts for Biofuel Synthesis

Current Organic Chemistry ◽

10.2174/1385272824999200726230556 ◽

2020 ◽

Vol 24 (16) ◽

pp. 1876-1891

Author(s):

Qiuyun Zhang ◽

Yutao Zhang ◽

Jingsong Cheng ◽

Hu Li ◽

Peihua Ma

Keyword(s):

Alternative Fuels ◽

Heterogeneous Catalysts ◽

Supported Catalysts ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Flexible Structures ◽

Biodiesel Production ◽

Biodiesel Synthesis ◽

Metal Organic ◽

Organic Framework

Biofuel synthesis is of great significance for producing alternative fuels. Among the developed catalytic materials, the metal-organic framework-based hybrids used as acidic, basic, or supported catalysts play major roles in the biodiesel production. This paper presents a timely and comprehensive review of recent developments on the design and preparation of metal-organic frameworks-based catalysts used for biodiesel synthesis from various oil feedstocks, including MILs-based catalysts, ZIFs-based catalysts, UiO-based catalysts, Cu-BTC-based catalysts, and MOFs-derived porous catalysts. Due to their unique and flexible structures, excellent thermal and hydrothermal stability, and tunable host-guest interactions, as compared with other heterogeneous catalysts, metal-organic framework-based catalysts have good opportunities for application in the production of biodiesel at industrial scale.

Download Full-text

Selective Styrene Oxidation to Benzaldehyde over Recently Developed Heterogeneous Catalysts

Molecules ◽

10.3390/molecules26061680 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1680

Author(s):

Marta A. Andrade ◽

Luísa M. D. R. S. Martins

Keyword(s):

Heterogeneous Catalysts ◽

Carbon Materials ◽

Oxygen Species ◽

Styrene Oxidation ◽

Reaction Conditions ◽

Reactive Metal ◽

Catalytic Systems ◽

Tert Butyl Hydroperoxide ◽

Metal Organic ◽

Important Intermediate

The selective oxidation of styrene under heterogeneous catalyzed conditions delivers environmentally friendly paths for the production of benzaldehyde, an important intermediate for the synthesis of several products. The present review explores heterogeneous catalysts for styrene oxidation using a variety of metal catalysts over the last decade. The use of several classes of supports is discussed, including metal–organic frameworks, zeolites, carbon materials and silicas, among others. The studied catalytic systems propose as most used oxidants tert-butyl hydroperoxide, and hydrogen peroxide and mild reaction conditions. The reaction mechanism proceeds through the generation of an intermediate reactive metal–oxygen species by catalyst-oxidant interactions. Overall, most of the studies highlight the synergetic effects among the metal and support for the activity and selectivity enhancement.

Download Full-text

Robust photocatalytic hydrogen production on metal-organic layers of Al-TCPP with ultrahigh turnover numbers

Chinese Chemical Letters ◽

10.1016/j.cclet.2021.05.035 ◽

2021 ◽

Author(s):

Hui Yu ◽

Xiang Wu ◽

Qiaoqiao Mu ◽

Zhihe Wei ◽

Yindong Gu ◽

...

Keyword(s):

Hydrogen Production ◽

Photocatalytic Hydrogen Production ◽

Organic Layers ◽

Metal Organic

Download Full-text

Replacement of Chromium by Non-Toxic Metals in Lewis-Acid MOFs: Assessment of Stability as Glucose Conversion Catalysts

Catalysts ◽

10.3390/catal9050437 ◽

2019 ◽

Vol 9 (5) ◽

pp. 437 ◽

Cited By ~ 8

Author(s):

Ralentri Pertiwi ◽

Ryan Oozeerally ◽

David L. Burnett ◽

Thomas W. Chamberlain ◽

Nikolay Cherkasov ◽

...

Keyword(s):

Heterogeneous Catalysts ◽

Metal Organic Framework ◽

Solid Acid Catalyst ◽

Acid Catalyst ◽

Major Product ◽

Hydrothermal Conditions ◽

Hydroxymethyl Furfural ◽

Extended Synthesis ◽

Metal Organic ◽

Optimum Material

The metal–organic framework MIL-101(Cr) is known as a solid–acid catalyst for the solution conversion of biomass-derived glucose to 5-hydroxymethyl furfural (5-HMF). We study the substitution of Cr3+ by Fe3+ and Sc3+ in the MIL-101 structure in order to prepare more environmentally benign catalysts. MIL-101(Fe) can be prepared, and the inclusion of Sc is possible at low levels (10% of Fe replaced). On extended synthesis times the polymorphic MIL-88B structure instead forms.Increasing the amount of Sc also only yields MIL-88B, even at short crystallisation times. The MIL-88B structure is unstable under hydrothermal conditions, but in dimethylsulfoxide solvent, it provides 5-HMF from glucose as the major product. The optimum material is a bimetallic (Fe,Sc) form of MIL-88B, which provides ~70% conversion of glucose with 35% selectivity towards 5-HMF after 3 hours at 140 °C: this offers high conversion compared to other heterogeneous catalysts reported in the same solvent.

Download Full-text

Metal–organic frameworks as catalytic selectivity regulators for organic transformations

Chemical Society Reviews ◽

10.1039/d0cs01538e ◽

2021 ◽

Author(s):

Jun Guo ◽

Yutian Qin ◽

Yanfei Zhu ◽

Xiaofei Zhang ◽

Chang Long ◽

...

Keyword(s):

Heterogeneous Catalysts ◽

Metal Organic Frameworks ◽

Research Topic ◽

Organic Transformations ◽

Catalytic Selectivity ◽

Challenging Research ◽

Metal Organic

Selective organic transformations using metal–organic frameworks (MOFs) and MOF-based heterogeneous catalysts have been an intriguing but challenging research topic in both the chemistry and materials communities.

Download Full-text

Selective Cyclohexene Oxidation to Allylic Compounds over Cu-triazole Framework via Homolytic Activation of Hydrogen Peroxide

Dalton Transactions ◽

10.1039/d1dt00227a ◽

2021 ◽

Author(s):

Panyapat Ponchai ◽

Kanyaporn Adpakpang ◽

Sareeya Bureekaew

Keyword(s):

Hydrogen Peroxide ◽

Heterogeneous Catalysts ◽

Metal Organic Frameworks ◽

Porous Structures ◽

Cyclohexene Oxidation ◽

Catalytic Sites ◽

P Utilization ◽

Metal Organic ◽

Activation Of Hydrogen Peroxide

Utilization of metal-organic frameworks as heterogeneous catalysts is crucial owing to their abundant catalytic sites and well-defined porous structures. Highly robust [Cu3(trz)3(μ3-OH)(OH)2(H2O)4]∙2H2O (trz = 1,2,4-triazole) was employed as a catalyst...

Download Full-text