Dioxygen splitting at room temperature over distant binuclear transition metal centers in zeolites for direct oxidation of methane to methanol

2021 ◽  
Author(s):  
Kinga Mlekodaj ◽  
Mariia Lemishka ◽  
Stepan Sklenak ◽  
Jiri Dedecek ◽  
Edyta Tabor
Keyword(s):  
Transition Metal ◽  
Room Temperature ◽  
Direct Oxidation ◽  
Metal Centers ◽  
Oxidation Of Methane ◽  
First Time

Here we demonstrate for the first time the splitting of dioxygen at RT over distant binuclear transition metal (M = Ni, Mn, and Co) centers stabilized in ferrierite zeolite. Cleaved...

Room-temperature conversion of the photoelectrochemical oxidation of methane into electricity at nanostructured TiO2

2021 ◽  
Vol 5 (1) ◽  
pp. 127-134
Author(s):  
Yanir Kadosh ◽  
Eli Korin ◽  
Armand Bettelheim
Keyword(s):  
Fuel Cell ◽  
Room Temperature ◽  
Nanotube Arrays ◽  
Nanostructured Tio2 ◽  
Oxidation Of Methane ◽  
Photoelectrochemical Oxidation ◽  
First Time ◽  
Room Temperature Operation

The room-temperature operation of a methane-based photo-fuel cell is demonstrated for the first time. This is achieved using a TiO2 nanotube arrays photoanode which shows effective oxidation of methane.

scholarly journals Transition Metal-Free Intramolecular Friedel-Crafts Reaction by Alkene Activation: A Method for the Synthesis of Some Novel Xanthene Derivatives

2021 ◽  
Author(s):  
Tülay Yıldız ◽  
İrem Baştaş ◽  
Hatice Başpınar Küçük
Keyword(s):  
Transition Metal ◽  
Trifluoroacetic Acid ◽  
Room Temperature ◽  
Synthesis Method ◽  
Biological Significance ◽  
Metal Free ◽  
New Synthesis ◽  
Starting Point ◽  
Xanthene Derivatives ◽  
First Time

In this work, new derivatives (substituted 9-methyl-9-arylxanthenes) of xanthene compounds (5a-5l) of possible biological significance were synthesized by developing a new synthesis method. In order to obtain xanthene derivatives, the original alkene compounds to be used as the starting point were synthesized in four steps using appropriate reactions. Cyclization reaction by intramolecular Friedel-Crafts alkylation was carried out in order to synthesize the desired xanthene derivatives using the alkenes as starting compounds. Intramolecular Friedel-Crafts reaction was catalyzed by trifluoroacetic acid (TFA) and provided some novel substituted 9-methyl-9-arylxanthenes with good yields at room temperature within 6–24 hours. As a result, an alkene compound was used for activation with TFA in the synthesis of xanthene through intramolecular Friedel-Crafts alkylation for the first time.

scholarly journals Transition-metal-free intramolecular Friedel–Crafts reaction by alkene activation: A method for the synthesis of some novel xanthene derivatives

2021 ◽  
Vol 17 ◽  
pp. 2203-2208
Author(s):  
Tülay Yıldız ◽  
İrem Baştaş ◽  
Hatice Başpınar Küçük
Keyword(s):  
Transition Metal ◽  
Trifluoroacetic Acid ◽  
Room Temperature ◽  
Synthesis Method ◽  
Biological Significance ◽  
Cyclization Reaction ◽  
Metal Free ◽  
New Synthesis ◽  
Xanthene Derivatives ◽  
First Time

In this work, new derivatives (substituted 9-methyl-9-arylxanthenes) of xanthene compounds (5a–l) of possible biological significance were synthesized by developing a new synthesis method. In order to obtain xanthene derivatives, the original alkene compounds to be used as the starting materials were synthesized in four steps using appropriate reactions. A cyclization reaction by intramolecular Friedel–Crafts alkylation was carried out in order to synthesize the desired xanthene derivatives using the alkenes as starting compounds. The intramolecular Friedel–Crafts reaction was catalyzed by trifluoroacetic acid (TFA) and provided some novel substituted 9-methyl-9-arylxanthenes with good yields at room temperature within 6–24 hours. As a result, an alkene compound was used for activation with TFA in the synthesis of xanthene through intramolecular Friedel–Crafts alkylation for the first time.

Methane activation by ZSM-5-supported transition metal centers

2021 ◽  
Author(s):  
Daniyal Kiani ◽  
Sagar Sourav ◽  
Yadan Tang ◽  
Jonas Baltrusaitis ◽  
Israel E. Wachs
Keyword(s):  
Transition Metal ◽  
Methane Activation ◽  
Group V ◽  
Metal Centers ◽  
Methane Dehydroaromatization

The literature on methane dehydroaromatization (MDA) to benzene using ZSM-5 supported, group V–VIII transition metal-based catalysts (MOx/ZSM-5) is critically reviewed with a focus on in situ and operando molecular insights.

Room-temperature white and color-tunable afterglow by manipulating multi-mode triplet emissions

2021 ◽  
Vol 9 (9) ◽  
pp. 3257-3263
Author(s):  
Jianwei Liu ◽  
Zhimin Ma ◽  
Zewei Li ◽  
Yan Liu ◽  
Xiaohua Fu ◽  
...  
Keyword(s):  
Room Temperature ◽  
Single Component ◽  
Color Tunable ◽  
First Time ◽  
Multi Mode

Two isomers pDCzPyCN and oDCzPyCN are designed and synthesized. Amazingly, oDCzPyCN manifest white afterglow at room temperature. This is the first time that single-component white afterglow has finally been realized.

scholarly journals Single-crystalline epitaxial TiO film: A metal and superconductor, similar to Ti metal

2021 ◽  
Vol 7 (2) ◽  
pp. eabd4248
Author(s):  
Fengmiao Li ◽  
Yuting Zou ◽  
Myung-Geun Han ◽  
Kateryna Foyevtsova ◽  
Hyungki Shin ◽  
...  
Keyword(s):  
Transition Metal ◽  
Density Functional ◽  
Tight Binding ◽  
Crystal Form ◽  
Titanium Monoxide ◽  
Binding Model ◽  
Functional Theory ◽  
Single Crystalline ◽  
First Time ◽  
Lattice Matched

Titanium monoxide (TiO), an important member of the rock salt 3d transition-metal monoxides, has not been studied in the stoichiometric single-crystal form. It has been challenging to prepare stoichiometric TiO due to the highly reactive Ti2+. We adapt a closely lattice-matched MgO(001) substrate and report the successful growth of single-crystalline TiO(001) film using molecular beam epitaxy. This enables a first-time study of stoichiometric TiO thin films, showing that TiO is metal but in proximity to Mott insulating state. We observe a transition to the superconducting phase below 0.5 K close to that of Ti metal. Density functional theory (DFT) and a DFT-based tight-binding model demonstrate the extreme importance of direct Ti–Ti bonding in TiO, suggesting that similar superconductivity exists in TiO and Ti metal. Our work introduces the new concept that TiO behaves more similar to its metal counterpart, distinguishing it from other 3d transition-metal monoxides.

scholarly journals Facile Green, Room-Temperature Synthesis of Gold Nanoparticles Using Combretum erythrophyllum Leaf Extract: Antibacterial and Cell Viability Studies against Normal and Cancerous Cells

Antibiotics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 893
Author(s):  
Olufunto T. Fanoro ◽  
Sundararajan Parani ◽  
Rodney Maluleke ◽  
Thabang C. Lebepe ◽  
Jose R. Varghese ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Cell Viability ◽  
Leaf Extract ◽  
Room Temperature ◽  
Klebsiella Oxytoca ◽  
Cost Effective ◽  
Average Diameter ◽  
Antibacterial Activities ◽  
Inhibition Concentration ◽  
First Time

We herein report a facile, green, cost-effective, plant-mediated synthesis of gold nanoparticles (AuNPs) for the first time using Combretum erythrophyllum (CE) plant leaves. The synthesis was conducted at room temperature using CE leaf extract serving as a reducing and capping agent. The as-synthesized AuNPs were found to be crystalline, well dispersed, and spherical in shape with an average diameter of 13.20 nm and an excellent stability of over 60 days. The AuNPs showed broad-spectrum antibacterial activities against both pathogenic Gram-positive (Staphylococcus epidermidis (ATCC14990), Staphylococcus aureus (ATCC 25923), Mycobacterium smegmatis (MC 215)) and Gram-negative bacteria (Proteus mirabilis (ATCC 7002), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 13822), Klebsiella oxytoca (ATCC 8724)), with a minimum inhibition concentration of 62.5 µg/mL. In addition, the as-synthesized AuNPs were highly stable with exceptional cell viability towards normal cells (BHK- 21) and cancerous cancer cell lines (cervical and lung cancer).

Free-standing electrochemically coated MoSx based 3D-printed nanocarbon electrode for solid-state supercapacitor application

Nanoscale ◽  
2021 ◽  
Author(s):  
Kalyan Ghosh ◽  
Martin Pumera
Keyword(s):  
Solid State ◽  
Transition Metal ◽  
Electrochemical Deposition ◽  
Room Temperature ◽  
Free Standing ◽  
Metal Chalcogenide ◽  
Supercapacitor Application ◽  
3D Printed

Room temperature electrochemical deposition of transition metal chalcogenide (MoSx) on 3D-printed nanocarbon fibers based electrodes for custom shaped solid-state supercapacitor.

Weak ferromagnetic response in PbZr1−xTixO3 single crystals

2019 ◽  
Vol 7 (36) ◽  
pp. 11085-11089
Author(s):  
Iwona Lazar ◽  
Monika Oboz ◽  
Jerzy Kubacki ◽  
Andrzej Majchrowski ◽  
Julita Piecha ◽  
...  
Keyword(s):  
Hysteresis Loop ◽  
Single Crystals ◽  
Room Temperature ◽  
Ferromagnetic Hysteresis ◽  
First Time ◽  
Ferromagnetic Hysteresis Loop ◽  
Weak Ferromagnetic

For the first time, a weak ferromagnetic hysteresis loop at room temperature has been observed in PbZr1−xTixO3 (PZT) single crystals.

Sign in / Sign up

Export Citation Format

Share Document