Synthesis, Characterization and Properties of Conjugated Poly(1-Alkyl-2,5-Pyrrylene Vinylene)

1997 ◽  
Vol 488 ◽  
Author(s):  
In Tae Kim ◽  
Ronald L. Elsenbaumer
Keyword(s):  
Molecular Weight ◽  
Conjugated Polymers ◽  
Band Gap ◽  
Organic Solvents ◽  
Optical Band Gap ◽  
Vis Spectroscopy ◽  
Electrical Conductivities ◽  
C Nmr

AbstractA series of poly(N-alkylpyrrylene vinylenes)( alkyl = methyl(l), hexyl(2), dodecyl(3)) have been synthesized from the monomer, N-alkyl-2,5-bis(thiophenylmethylene)pyrrole, by base induced elimination and polymerization. The resulting deep purple conjugated polymers (2, 3) were soluble in a variety organic solvents. The electrical conductivities of the polymers lie in the range, 10−2 to 2.5 S/cm. The highest yield was obtained when the polymers were synthesized in refluxing THF with a monomer/ base mole ratio of 1/4. The optical band gap of the undoped polymers were 1.89 eV(1), 1.69 eV(2) and 1.65 eV(3). Characterization of the polymers includes IR, CV, 1H and 13C NMR, UV-vis spectroscopy, TGA and molecular weight studies.

Synthesis and spectral characterization of bis(β-diketonato)zirconium(IV) and -hafnium(IV) phthalocyaninates

2002 ◽  
Vol 06 (02) ◽  
pp. 114-121 ◽  
Author(s):  
L. A. Tomachynski ◽  
V. Ya. Chernii ◽  
S. V. Volkov
Keyword(s):  
Organic Solvents ◽  
Elemental Analysis ◽  
Central Atom ◽  
Spectral Characterization ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Cl Atoms

The reaction of PcMCl 2 ( M = Zr , Hf ) with β-diketones is reported. 1 H NMR and elemental analysis suggest the substitution of two Cl atoms for two β-diketone fragments takes place as a result of this reaction and the complexes PcM(β-dik)2 are formed. All obtained complexes are stable and highly soluble in most organic solvents. The data from 1 H and 19 F NMR, and UV-vis spectroscopy suggest the coordination of two β-diketone ligands in a cis geometry about the central atom of the macrocycle. It was shown bis(β-diketonato)zirconium(IV) and hafnium(IV) phthalocyanines containing β-diketones with donor or acceptor groups or with bulky substituents can be obtained.

scholarly journals Synthesis of Fluorene Based Alternating Copolymers using Direct Arylation Polymerization

2021 ◽  
Vol 33 (2) ◽  
pp. 393-398
Author(s):  
Mohd Sani Sarjadi ◽  
Yap Leong Khen ◽  
Xin Lin Wong ◽  
Zuhair Jamain ◽  
Md Lutfor Rahman
Keyword(s):  
Solar Cell ◽  
Band Gap ◽  
Active Layer ◽  
Optical Band Gap ◽  
Direct Arylation ◽  
Low Band Gap ◽  
Alternating Copolymers ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Direct Arylation Polymerization

Many researches have been done to obtain a low band gap and high Polymeric solar cell (PSCs) polymer either by creating new polymer or revising reported polymers from previous studies. In present work, two new copolymers were synthesized through direct arylation polymerization to produce poly(9,9-didodecylfluorene-alt-benzo[c][1,2,5]thiadiazole (P1) and poly(9,9-didodecylfluorene-altthieno[ 3,2-b]thiophene) (P2). The P1 and P2 are donor-accepter copolymers. P1 and P2 were compared to investigate its suitability to be applied in PSCs. The polymers obtained were characterized using FT-IR, NMR and UV-Vis spectroscopy. P1 shows two adsorption bands at λmax1 = 243 nm and λmax2 = 320 nm, whereas P2 also shows two adsorption bands at λmax1 = 243 nm and λmax2 = 427 nm. The optical band gap was calculated, P1 enabled band gap of 3.88 eV while P2 showed band gap of 2.91 eV. This work could be provided an insight to design and synthesize more efficient fluorene-based copolymers as active layer of PSCs in due course.

scholarly journals Controlled and cellulose eco-friendly synthesis and characterization of Bi2O2CO3 quantum dot nanostructures (QDNSs) and drug delivery study

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hojat Samarehfekri ◽  
Hamid Reza Rahimi ◽  
Mehdi Ranjbar
Keyword(s):  
Quantum Dot ◽  
Optical Band Gap ◽  
Biological Therapy ◽  
Skin Extract ◽  
Force Microscopy ◽  
Atomic Force ◽  
Vis Spectroscopy ◽  
Different Temperatures ◽  
Green Capping Agent

AbstractThis work aimed to prepare solvent-free or green Bi2O2CO3 for quantum dot nanostructures (QDNSs) based on cellulose as a stabilizer and green capping agent to sorafenib delivery for liver targeting. Because the walnut tree is one of the most abundant trees in Iran, it was tried to synthesize Bi2O2CO3 QDNSs using a walnut skin extract. The saturation magnetization for Bi2O2CO3 QDNSs was calculated to be 68.1. Also, the size of products was measured at around 60–80 nm with the Debye–Scherrer equation. Moreover, the morphology, functional groups, and crystallography of the Bi2O2CO3 nanoparticles were investigated using atomic force microscopy, scanning electron microscopy, vibrating-sample magnetometer, and Uv–vis spectroscopy. The results demonstrated that Bi2O2CO3 QDNSs have opto-magnetic properties and they can be suggested as the candidate materials for the sorafenib delivery on the liver tissue. The optical band gap estimated for Bi2O2CO3 QDNSs was found to be red-shift from 3.22 eV. This study suggests the preparation of the Bi2O2CO3 QDNSs based on cellulose as new opto-magnetic materials at different temperatures of 180 °C, 200 °C, 220 °C, and 240 °C for sorafenib delivery as a type of biological therapy drug.

scholarly journals Green Synthesis and Characterization of Gallium(III) Sulphide (α-Ga2S3) Nanoparicles at Room Temperature

Nano Hybrids ◽  
2014 ◽  
Vol 6 ◽  
pp. 37-46 ◽  
Author(s):  
Tansir Ahamad ◽  
Saad M. Alshehri
Keyword(s):  
Green Synthesis ◽  
Band Gap ◽  
Raman Spectra ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Blue Shift ◽  
Synthesis And Characterization ◽  
Spectroscopic Techniques ◽  
Sodium Thiosulphate

Two different batches of Gallium (III) sulphide nanocrystals, (α-Ga2S3)1 and (α-Ga2S3)2 were synthesized at room temperature by the reaction of Gallium (III) chloride with sodium thiosulphate in water for 10 and 20 min respectively. The resultant nanoparticles were characterized by different spectroscopic techniques. TEM micrographs showed well-defined, close to hexagonal particles, and the lattice fringes in the HRTEM images confirmed their nanocrystalline nature. The sizes of (α-Ga2S3)1 and (α-Ga2S3)2 were 12 and 35 nm respectively with similar morphologies. Optical band gap energies (3.43 eV/3.41 eV) and photoluminescence peaks 635/641 nm (red shift) and 414/420 nm (blue shift) of the synthesized α-Ga2S3 nanocrystals suggest that they may be promising photocatalysts. Raman spectra for the α-Ga2S3, shows very sharp bands at 119, 135 and 148 cm-1 due to Ga-S2 scissoring.

Synthesis and Optical properties of Perylene Bisimide Incorporated Low Bandgap Polymers for Photovoltaics

2009 ◽  
Vol 1154 ◽  
Author(s):  
Sivamurugan Vajiravelu ◽  
suresh valiyaveettil
Keyword(s):  
Optical Properties ◽  
Solid State ◽  
Conjugated Polymers ◽  
Chemical Structure ◽  
Optical Band Gap ◽  
Visible Region ◽  
Perylene Diimide ◽  
Low Bandgap ◽  
Perylene Bisimide ◽  
C Nmr

AbstractHerein we report on the synthesis of perylene diimide (PDI) based P1 and P2 conjugated polymers via Suzuki polymerization. The chemical structure of the polymers was elucidated using GPC, 1H, 13C NMR and elemental analysis. The absorption spectra of polymers were in the visible region from 250 – 800 nm in solution and in solid state. The optical band gap was (Egopt) found to be between 1.60 – 1.83 eV in solid state.

Spectroscopic and sub optical band gap properties of e-beam irradiated ultra-high molecular weight polyethylene

2015 ◽  
Vol 117 ◽  
pp. 172-177 ◽  
Author(s):  
Hamna Khan ◽  
Bilal Gahfoor ◽  
Malik Sajjad Mehmood ◽  
Manzoor Ahmad ◽  
Tariq Yasin ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Band Gap ◽  
High Molecular Weight ◽  
Optical Band Gap ◽  
Ultra High Molecular Weight

Organic–inorganic hybrid thin films based in HfO2 nanoparticles as dielectric for flexible electronics

2014 ◽  
Vol 92 (7/8) ◽  
pp. 806-812 ◽  
Author(s):  
R. Ambrosio ◽  
O. Arciniega ◽  
A. Carrillo ◽  
M. Moreno ◽  
A. Heredia ◽  
...  
Keyword(s):  
Band Gap ◽  
Hybrid Material ◽  
Flexible Electronics ◽  
Photoelectron Spectroscopy ◽  
Hafnium Oxide ◽  
Optical Band Gap ◽  
Low Cost ◽  
Sol Gel ◽  
Inorganic Hybrid

In this work the synthesis and characterization of an organic–inorganic hybrid composite film based on hafnium oxide (HfO2) and polyvinylpyrrolidone (PVP) with dielectric properties is presented. These films were prepared using the sol-gel process adjusting the chemical composition to tailor the material properties, such as the dielectric and the optical band gap. The HfO2 was obtained by the hydrolysis of hafnium chloride (HfCl4) under catalysis of ethanol and deionized water, later the PVP was subsequently added to complete the hydrolysis. Finally the films were dried at 150 °C. The structural characterization of the hybrid material showed a hafnium nanoparticle size around 100 nm into the polymer matrix. The chemical structure and the high purity of the hybrid material were corroborated by X-ray photoelectron spectroscopy measurements, which showed the bounding of HfO2–PVP. The electrical characterization demonstrated that the nanostructured materials with hafnium nanoparticles improve the dielectric constant in the films with values around k = 18.5. The optical band gap, Eo, was obtained from 4 to 5.7 eV. These characteristics in our hybrid material are very promising for flexible electronics applications with the advantage of its low temperature, thermal stability, and low cost process of deposition.

scholarly journals Nanoparticles of Low Optical Band Gap Conjugated Polymers

2012 ◽  
Vol 45 (19) ◽  
pp. 7799-7805 ◽  
Author(s):  
Johannes Huber ◽  
Christoph Jung ◽  
Stefan Mecking
Keyword(s):  
Conjugated Polymers ◽  
Band Gap ◽  
Optical Band Gap

scholarly journals Studies on the growth and characterization of L-cysteine hydrogen fluoride single crystal

2019 ◽  
Vol 37 (3) ◽  
pp. 304-309
Author(s):  
Azeezaa Varsha Mohammed ◽  
Suresh Sagadevan
Keyword(s):  
Single Crystal ◽  
Hydrogen Fluoride ◽  
Grown Crystal ◽  
Optical Band Gap ◽  
Second Harmonic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ft Ir

AbstractL-cysteine hydrogen fluoride (LCHF) single crystals were grown from aqueous solution. Single crystal X-ray diffraction, FT-IR, UV-Vis-NIR, and TG-DTA were used to test the grown crystals. The specimen dielectric and mechanical behaviors were also studied. Powder X-ray diffraction of the grown crystal was recorded and indexed. The optical properties of the LCHF crystal were determined using UV-Vis spectroscopy. It was found that the optical band gap of LCHF was 4.8 eV. The crystal functional groups were identified using FT-IR. Second harmonic generation (SHG) efficiency of the LCHF was three times higher than that of KDP. The dielectric constant, dielectric loss and AC conductivity were measured at different frequencies and temperatures.

Bioconjugation of papain with poly(N-vinylpyrrolidone): NMR characterization and study of its enzymatic activity

2021 ◽  
Vol 99 (1) ◽  
pp. 10-17
Author(s):  
L.E. Verduzco ◽  
Ana L. García-Pérez ◽  
Ramiro Guerrero-Santos ◽  
Antonio Ledezma-Pérez ◽  
Jorge Romero-García ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Catalytic Activity ◽  
Chain Transfer ◽  
Gel Permeation Chromatography ◽  
Acid Group ◽  
H Nmr ◽  
Reversible Addition ◽  
Nmr Characterization ◽  
Vis Spectroscopy ◽  
C Nmr

A poly(vinylpyrrolidone) end-functionalized with a carboxylic acid group (PVP–CO2H) was synthesized by reversible addition-fragmentation chain transfer (RAFT)/macromolecular design via the interchange of xanthates (MADIX) polymerization mediated by 4-(O-ethylxanthyl)methyl benzoic acid. The molecular weight of the as-synthesized PVP–CO2H was estimated through UV–vis spectroscopy (Mn(UV–vis) = 7322 g/mol), gel permeation chromatography (GPC) (Mn(GPC) = 8670 g/mol), and 1H NMR, (Mn(NMR) = 8207 g/mol). The values obtained were close with the theoretical molecular weight (Mn(th) = 7925 g/mol). Subsequently, the preformed PVP–CO2H was activated to produce N-succinimidyl poly(vinylpyrrolidone) (PVP–NHS). This precursor was covalently coupled to papain to produce bioconjugate PVP–papain. The functional group modifications in the PVP chain-end were observed by the variations in the chemical shift values by 1H and 13C NMR and FTIR analysis at each step of the synthesis. The molecular weight of the PVP–papain was obtained by SEC–HPLC and suggests that, on average, four or five chains of PVP–CO2H were attached to one papain molecule. Compared with papain, the PVP–papain exhibited significantly improved catalytic activity, pH, and thermal stability. Additionally, the storage studies showed that the catalytic activity of PVP–papain was about 79% versus the native enzyme (29%), and this activity was maintained even when it was stored for 25 days.

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