Strain effect on the catalytic activities of B- and B/N-doped black phosphorene for electrochemical conversion of CO to valuable chemicals

2020 ◽  
Vol 8 (24) ◽  
pp. 11986-11995
Author(s):  
Zhe Chen ◽  
Xin Liu ◽  
Jingxiang Zhao ◽  
Yan Jiao ◽  
Lichang Yin
Keyword(s):  
Compressive Strain ◽  
Strain Effect ◽  
Metal Free ◽  
Catalytic Activities ◽  
Electrochemical Conversion ◽  
Black Phosphorene

Designed metal-free electrocatalysts combined with compressive strain can efficiently convert CO to valuable chemicals and fuels.

Effects of substituted metal-free porphyrins in apo-horseradish peroxidase

2007 ◽  
Vol 11 (12) ◽  
pp. 836-845
Author(s):  
A. Molaei Rad ◽  
A. Akbar Moosavi-Movahedi ◽  
Hedayatollah Ghourchian ◽  
Nasser Safari ◽  
Jun Hong ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Horseradish Peroxidase ◽  
Fluorescence Emission ◽  
Potassium Phosphate ◽  
Phosphate Solution ◽  
Metal Free ◽  
Catalytic Activities ◽  
Polar Environment ◽  
Free Metal ◽  
Steric Hindrances

The peroxidase-like catalytic activities of some synthetic porphyrins following substitution in apo-horseradish peroxidase (apo-HRP) were studied by UV-vis and fluorescence spectrophotometries in buffer potassium phosphate solution at pH 7. The insertion of these synthetic porphyrins in apo-HRP is very difficult, due to steric hindrances between coordinated metals in porphyrins and the side-chains of amino acids in native protein. However, because of planar coordination following insertion in an active site of apo-HRP tetrapyridylporphyrin(TPyP), a metal-free porphyrin, adsorbs free metal ions from the environment and shows higher peroxidase-like catalytic activity than other new synthetic porphyrins. The results indicate that the metal-free porphyrins with optimum Reinheitzahl (RZ) show higher catalytic activity relative to others. The fluorescence emission of TPyP only, and of apo-HRP-TPyP, displayed significantly different wavelengths for the maximum aromatic fluorescence intensity. The λmax for apo-HRP-TPyP was around 447 nm, while for TPyP, alone, it increased to 463 nm, which showed that the aromatic groups' surroundings changed upon substitution of porphyrins in a low polar environment.

Composition-Dependent Catalytic Activities of Noble-Metal-Free NiS/Ni3S4 for Hydrogen Evolution Reaction

2016 ◽  
Vol 120 (27) ◽  
pp. 14581-14589 ◽  
Author(s):  
Zhixiao Qin ◽  
Yubin Chen ◽  
Zhenxiong Huang ◽  
Jinzhan Su ◽  
Zhidan Diao ◽  
...  
Keyword(s):  
Hydrogen Evolution ◽  
Noble Metal ◽  
Hydrogen Evolution Reaction ◽  
Metal Free ◽  
Catalytic Activities

Nitrogen-enriched polydopamine analogue-derived defect-rich porous carbon as a bifunctional metal-free electrocatalyst for highly efficient overall water splitting

2017 ◽  
Vol 5 (32) ◽  
pp. 17064-17072 ◽  
Author(s):  
Zheye Zhang ◽  
Zhengran Yi ◽  
Juan Wang ◽  
Xin Tian ◽  
Pei Xu ◽  
...  
Keyword(s):  
Water Splitting ◽  
Porous Carbon ◽  
Free Water ◽  
Metal Free ◽  
Catalytic Activities ◽  
Highly Efficient ◽  
Overall Water Splitting ◽  
Carbon Based

A carbon-based, bifunctional metal-free water splitting electrocatalyst is prepared using a nitrogen-enriched polydopamine analogue to produce defect-rich porous carbon, which exhibits superb catalytic activities for both the HER and the OER.

Metal-free and metal porphyrins: A highly efficient catalysts to Li/SOCl2 battery

2015 ◽  
Vol 19 (12) ◽  
pp. 1219-1224 ◽  
Author(s):  
Na Li ◽  
Chong Dang ◽  
Wanjun Sun ◽  
Jinning Dang ◽  
Xinsheng Lu ◽  
...  
Keyword(s):  
Thionyl Chloride ◽  
Discharge Time ◽  
Metal Free ◽  
Catalytic Activities ◽  
Metal Porphyrins ◽  
Highly Efficient ◽  
High Efficient ◽  
Battery Discharge ◽  
First Time

Two metal-free porphyrins H[Formula: see text]Pp (a, b) and four metalloporphyrins CuPp (a, b) and ZnPp (a, b) have been applied to lithium/thionyl chloride (Li/SOCl[Formula: see text] battery as the high efficient catalysts for the first time. Notably, the battery discharge time in blank is only 1080 s while that of Li/SOCl2 battery after adding porphyrin/metalloporphyrins is 1980 s for H[Formula: see text]Pp (a), 2160 s for H[Formula: see text]Pp (b), 1560 s for CuPp (a), 1320 s for CuPp (b), 1620 s for ZnPp (a), and 1680 s for ZnPp (b), respectively. Furthermore, the energy of the battery whose electrolyte contains the H[Formula: see text]Pp (a, b), CuPp (a, b) and ZnPp (a, b) increases by approximately 11.88–77.14% than that of the battery without them. And the metal-free porphyrins H[Formula: see text]Pp (a) or H[Formula: see text]Pp (b) exhibit higher catalytic activities than that of metalloporphyrins CuPp (a, b) and ZnPp (a, b). In addition, the possible reasons to explain the excellent results were also analyzed.

Superlattice Interface and Lattice Strain Study by Ion Channeling

1983 ◽  
Vol 25 ◽  
Author(s):  
C. K. Pan ◽  
D. C. Zheng ◽  
W. K. Chu ◽  
C.-A. Chang
Keyword(s):  
Lattice Strain ◽  
Ion Beam ◽  
Compressive Strain ◽  
Angular Position ◽  
Angle Measurement ◽  
Strain Effect ◽  
Individual Layer ◽  
Ion Channeling ◽  
Kink Angle ◽  
Good Agreement

EXTENDED ABSTRACTWe have studied the interface and the lattice strain of superlattices by ion channeling technique. The objective in this work is to verify the existence of alternating tensile and compressive strain in the superlattice and to develop a method for measuring the lattice strain directly. Alternating layers of GaSb/Al Sb were grown epitaxially by MBE with 10 periods. The thickness of each individual layer is 30 nm. Channeling measurements and analysis were made using a 1.76 MeV 4He ion beam. The measurements reveal higher dechanneling along the [110] axis than along the [100] axis. This is consistent with the dechanneling results published earlier. The high dechanneling along the [110] axis has been considered due to the lattice strain that occurs in the layers caused by the slight mismatch between the lattice constants of the two materials. The strain effect make [110] axis slightly bent from layer to layer (“zigzag”), but it does not occur in [100] axis. The axial angular scan analyses were made around the [110] direction at the different depths using a movable energy window setting. We have found that the angular position of the best alignment shifts from layer to layer. The oscillation of those angular positions with depth is of a direct evidence of the existence of alternating tension and compression strain layers in the superlattice. The “kink” angle at the interface is given by the difference of the angular position between the first and second layer. This is found to be 0.17° ± 0.03 %. This is in a good agreement with the result calculated from elasticity. Preliminary result of this experiment is recently published.3We are also investigating the interface and lattice strain by planar angular scan across the (110) plane at a position three degrees from [110] axis.The similar oscillatory results have been found for {110} planar channeling and the “kink” angle measurement is in a good agreement with the results from axial angular scan.We believe that the method of ion beam channeling and angular scan is very effective in strain measurements in multi-layered heteroexpitaxy system.3. W. K. Chu, C. K. Pan and C.-A. Chang, Phys. Rev. Rapid Communication B28, 4033 (1983).

Characterization of InN-In0.25Ga0.75N Quantum Well Laser with In0.4Al0.6N Layers for 1300 nm Band

MRS Advances ◽  
2016 ◽  
Vol 1 (28) ◽  
pp. 2051-2057 ◽  
Author(s):  
Md. Mobarak Hossain Polash ◽  
Kamruzzaman Khan
Keyword(s):  
Optical Properties ◽  
Numerical Model ◽  
Quantum Well ◽  
Electronic Band Structure ◽  
Compressive Strain ◽  
Strain Effect ◽  
Transition Elements ◽  
Electronic Band ◽  
Layer Width ◽  
Quantum Well Laser

ABSTRACTA wurtzite-strained nitride Quantum Well Laser has been characterized for short distance communication wavelength. InN and In0.25Ga0.75N have been chosen as well material and barrier material respectively with In0.4Al0.6N SCH layers at the end of barrier layers to improve the carrier and photon confinement within the active region. This structure shows less compressive strain (7.33%) with respect to previously proposed structure which makes the structure more suitable for fabrication. To obtain the electronic band structure, self-consistent method with k.p formalism has been performed where valence band mixing effect, strain effect and spontaneous and piezoelectric polarization effect has been included. From the electronic characteristics, the optical properties have been performed with numerical model. From the optical properties, the structure has been found as TE polarized with C1-HH1, C1-LH1, C2-HH1 and C2-LH1 dominating transition elements. From the performance of the numerical model, 4731.98 cm−1 optical gain for TE polarization at 1315.5 nm emission wavelength and 8.017×1027 cm−3s−1eV−1 spontaneous emission rate at 1301.7nm wavelength have been found for 12Å well width, 17Å barrier width and 52Å SCH layer width at 5×1019 cm−3 carrier density. The obtained properties have been shown a good agreement with previously published works.

Anisotropic Strain Effect on Electron Transport in C60 Organic Field Effect transistors

2013 ◽  
Vol 1501 ◽  
Author(s):  
Akash Nigam ◽  
Günther Schwabegger ◽  
Mujeeb Ullah ◽  
Rizwan Ahmed ◽  
Ivan I. Fishchuk ◽  
...  
Keyword(s):  
Electron Transport ◽  
Charge Transport ◽  
Field Effect ◽  
High Performance ◽  
Tensile Strain ◽  
Field Effect Transistors ◽  
Compressive Strain ◽  
Strain Effect ◽  
Wearable Electronics ◽  
Organic Field Effect Transistors

ABSTRACTMechanical flexibility is one of the key advantages of organic semiconducting films in applications such as wearable-electronics or flexible displays. The present study is aimed at gaining deeper insight into the effect of strain on charge transport properties of the organic semiconductor films. We have fabricated high performance C60 top gate organic field effect transistors (OFET) on flexible substrates and characterized the devices by curling the substrates in concave and convex manner, to apply varying values of compressive and tensile strain, respectively. Electron mobility is found to increase with compressive strain and decrease with tensile strain. The observed strain effect is found to be strongly anisotropic with respect to the direction of flow of current. This observation on mobility is quantified using an Extended Gaussian Disorder Model (EGDM) for the hopping charge transport. We suggest that the observed strain dependence of the electron transport is dominated by a change in the effective charge hopping distance over the grain boundaries in polycrystalline C60 films.

scholarly journals Carbon Supported Alkaline Catalysts for Guerbet Coupling of Bioethanol

2017 ◽  
Author(s):  
György Onyestyák
Keyword(s):  
Activated Carbon ◽  
Chain Length ◽  
Reaction Temperature ◽  
Total Pressure ◽  
Aldol Reaction ◽  
Metal Free ◽  
Catalytic Activities ◽  
Heterogeneous Catalytic ◽  
Flow Through ◽  
Fuel Industry

Bioethanol valorization to butanol by continuous heterogeneous catalytic self-alkylation provides an option for the fuel industry. Dimerization of ethanol (E) was studied over activated carbon supported metal loaded and metal-free alkaline catalysts using a flow-through tube microreactor, applying WHSVE of 0.20-2.0 gE/h gcat. , 21 bar total pressure and 275-400°C reaction temperature. Activated carbon (AC) was impregnated with various alkaline salts as the catalysts of the aldol reaction. Different basicity of the investigated catalysts resulted in differing catalytic activities. Butanol was the product of highest yield. Longer chain primary aliphatic alcohols, having even number of carbon atoms were also obtained with yield decreasing significantly with increasing chain length.

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