Construction of unique six-coordinated titanium species with an organic amine ligand in titanosilicate and their unprecedented high efficiency for alkene epoxidation

2015 ◽  
Vol 51 (43) ◽  
pp. 9010-9013 ◽  
Author(s):  
Le Xu ◽  
Da-Ding Huang ◽  
Chen-Geng Li ◽  
Xinyi Ji ◽  
Shaoqing Jin ◽  
...  

An organic–inorganic titanosilicate with an amine ligand shows high catalytic activity, selectivity and recyclability in alkene epoxidation.

2013 ◽  
Vol 91 (4) ◽  
pp. 292-299 ◽  
Author(s):  
Bayardo E. Velasco ◽  
Gustavo López-Téllez ◽  
Nelly González-Rivas ◽  
Iván García-Orozco ◽  
Erick Cuevas-Yañez

Diverse dithioic acid copper complexes exhibit a high catalytic activity in the copper-catalyzed alkyne–azide cycloaddition using several solvents under different temperatures, showing a high efficiency with only 0.005 mmol catalyst/mmol alkyne or less. A dithioic acid copper complex derived from acetophenone was selected and used as the catalyst in the preparation of a library of 1,4-disubstituted-1,2,3-triazoles. This process occurred in high yields and good functional group tolerance.


RSC Advances ◽  
2015 ◽  
Vol 5 (96) ◽  
pp. 78441-78447 ◽  
Author(s):  
Phan Huy Hoang ◽  
Bach Nguyen Xuan

The magnetically recyclable ZSM-5 zeolite (MZZ) with high catalytic activity, high efficiency in separation, recycling and long lifetime for epoxide isomerization reaction was presented.


2021 ◽  
Author(s):  
Jianguo liu ◽  
Jiangmin Sun ◽  
Longlong Ma

The development of high efficiency, excellent selectivity, and super activity metal catalyst for chemical selective hydrogenation of alkynes to olefin is of great significance in the field of the chemical industry. At the same time, the development of a large number of available base metal catalysts for organic conversion remains an important objective of chemical research. Herein, we report a facile preparation of a simple, high catalytic activity, environmentally friendly, and inexpensive biomass carbon material supported nano-nickel catalyst from lignin residue. The entire preparation process of the catalyst is simple, reliable, economical, and environmentally friendly, which provides a potential utilization prospect for large-scale industrial applications of biomass-based carbon material catalysts. Biomass-based lignin residues can not only reduce the high oxidation state of nickel ions into nickel nanoparticles by the in-situ reducing gas generated during the calcination process, but the mesoporous structure of lignin residue also promotes the adsorption of nickel metal, which greatly improved the catalytic activity of biomass-based Ni-based catalysts. The simple synthetic green, cost-effective and sustainable biomass-based Ni-based catalyst shows good performance in the selective hydrogenation of phenylacetylene, reaching 97.2% conversion and 84.3% styrene selectivity, respectively.


2019 ◽  
Vol 55 (29) ◽  
pp. 4218-4221 ◽  
Author(s):  
Lingxi Zhou ◽  
Meichen Guo ◽  
Yao Li ◽  
Qin Gu ◽  
Wenqian Zhang ◽  
...  

A series of wire-in-plate nanostructured electrocatalysts for OER with high catalytic activity were fabricated.


Author(s):  
Libo Deng ◽  
Xiujuan Li ◽  
Yuanyuan Chen ◽  
Weijie Liao ◽  
Lei Qiu ◽  
...  

Single atom catalysts (SACs) stabilized by nitrogen in a carbon support and having maximized atom utilization efficiency and an unsaturated environment exhibit high catalytic activity and selectivity. Incorporating nitrogen into...


2013 ◽  
Vol 453 (3) ◽  
pp. 447-454 ◽  
Author(s):  
Liu Xue ◽  
Shurong Hou ◽  
Min Tong ◽  
Lei Fang ◽  
Xiabin Chen ◽  
...  

Cocaine is a widely abused drug without an FDA (Food and Drug Administration)-approved medication. It has been recognized that an ideal anti-cocaine medication would accelerate cocaine metabolism producing biologically inactive metabolites via a route similar to the primary cocaine-metabolizing pathway, i.e. human BChE (butyrylcholinesterase)-catalysed hydrolysis. However, the native human BChE has a low catalytic activity against cocaine. We recently designed and discovered a BChE mutant (A199S/F227A/S287G/A328W/Y332G) with a high catalytic activity (kcat=5700 min−1, Km=3.1 μM) specifically for cocaine, and the mutant was proven effective in protecting mice from acute cocaine toxicity of a lethal dose of cocaine (180 mg/kg of body weight, LD100). Further characterization in animal models requires establishment of a high-efficiency stable cell line for the BChE mutant production at a relatively larger scale. It has been extremely challenging to develop a high-efficiency stable cell line expressing BChE or its mutant. In the present study, we successfully developed a stable cell line efficiently expressing the BChE mutant by using a lentivirus-based repeated-transduction method. The scaled-up protein production enabled us to determine for the first time the in vivo catalytic activity and the biological half-life of this high-activity mutant of human BChE in accelerating cocaine clearance. In particular, it has been demonstrated that the BChE mutant (administered to mice 1 min prior to cocaine) can quickly metabolize cocaine and completely eliminate cocaine-induced hyperactivity in rodents, implying that the BChE mutant may be developed as a promising therapeutic agent for cocaine abuse treatment.


2019 ◽  
Vol 7 (38) ◽  
pp. 22084-22091 ◽  
Author(s):  
Deng-Yue Zheng ◽  
En-Xuan Chen ◽  
Chun-Rong Ye ◽  
Xiao-Chun Huang

For the first time, fullerene (C60) was used to enhance the photogenerated electron–hole separation of MOFs as a catalyst and showed high catalytic activity in the photocatalytic oxidation of thioether in air.


Author(s):  
Haona Zhang ◽  
Wei Wei ◽  
Shuhua Wang ◽  
Hao Wang ◽  
Baibiao Huang ◽  
...  

In the light of the ultrahigh atom utilization, high catalytic activity and low cost, single-atom catalysts (SACs) have been garnering extensive attention in the field of electrochemistry. In recent studies,...


MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2961-2972
Author(s):  
P.C. Meléndez-González ◽  
E. Garza-Duran ◽  
J.C. Martínez-Loyola ◽  
P. Quintana-Owen ◽  
I.L. Alonso-Lemus ◽  
...  

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).


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