SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL PROPERTIES OF 4-[（4-HYDROXYBENZYLIDENE） AMINO] PHENOL AND ITS POLYMER

The oxidative polycondensation reaction conditions of 4-[(4-hydroxybenzylidene)amino]phenol(4-HBAP)were studied with H_2O_2,air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃.The structures of the obtained monomer and polymer were confirmed by FT-IR,UV-Vis,~1H-and ~(13)C-NMR and elemental analysis.The characterization was made by TG-DTA,size exclusion chromatography(SEC)and solubility tests.At the optimum reaction conditions,the yield of poly[4-(4-hydroxybenzylidene amino)phenol](P-4-HBAP)was found to be 48.3%(for H_2O_2 oxidant),80.5%(for air O_2 oxidant)and 86.4%(for NaOCl oxidant).According to the SEC analysis,the number-average molecular weight(M_n),weight-average molecular weight(M_w)and polydispersity index(PDI)values of P-4-HBAP was found to be 8950,10970 g mol~(-1) and 1.225,respectively,using H_2O_2;and 11610,15190 g mol~(-1) and 1.308 respectively, using air O_2 and 7900,9610 g mol~(-1) and 1.216,respectively,using NaOCl.According to TG-DTA analyses,P-4-HBAP was more stable than 4-HBAP against thermal decomposition.The weight loss of P-4-HBAP was found to be 49.27% at 1000℃. The highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)values calculated from electrochemical measurement.Electrochemical energy gaps(E′_g)of 4-HBAP and P-4-HBAP were found to be-5.46, -5.28;-2.26,-2.67;3.20 and 2.61 eV,respectively.According to UV-Vis measurements,optical band gap(E_g)of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV,respectively.Also,antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria.The electrical conductivity of the polymer was measured after doping with iodine.     

SYNTHESIS, CHARACTERIZATION, THERMAL ANALYSIS, CONDUCTIVITY AND BAND GAPS OF OLIGO {4-[(2-HYDROXYL-1-NAPHTHYL)METHYLENE]-AMINOBENZOIC ACID}

The oxidative polycondensation reaction conditions of 4-[(2-hydroxyl-1-naphthyl)methylene]aminobenzoic acid (4-HNMABA) with H_2O_2,air O_2 and NaOCl were studied in an aqueous alkaline medium between 40℃and 90℃.The structure of oligo {4-[(2-hydroxyl-1-naphthyl)methylene]aminobenzoic acid} (O-4-HNMABA) was characterized by using ~1H-NMR,~(13)C-NMR,FT-IR,UV-Vis,size exclusion chromatography (SEC) and elemental analysis techniques.At the optimum reaction conditions,the yield of O-4-HNMABA was found to be 70...     

Synthesis, characterization, thermal stability and electrochemical properties of poly-4-[(2-methylphenyl)iminomethyl]phenol

In this study, the reaction conditions of poly-4-[(2-methylphenyl)iminomethyl]phenol (P-2-MPIMP) were studied by using oxidants such as air O₂, H₂O₂ and NaOCl in an aqueous alkaline medium between 50 and 90 °C. The structures of the synthesized monomer and polymer were confirmed by FT-IR, UV-vis, NMR and elemental analysis. The characterization was made by TG-DTA, size exclusion chromatography (SEC) and solubility tests. At the optimum reaction conditions, the yield of poly-4-[(2-methylphenyl)iminomethyl]phenol (P-2-MPIMP) was found to be 20% (for air O₂ oxidant), 33% (for H₂O₂ oxidant), and 74% (for NaOCl oxidant). According to the SEC analysis, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of P-2-MPIMP were found to be 3300, 4100 g mol⁻¹ and 1.242, using H₂O₂, and 4550, 5150 g mol⁻¹and 1.132, using air O₂ and 5300, 5850 g mol⁻¹ and 1.104, using NaOCl, respectively. According to TG analysis, the weight losses of 4-[(2-methylphenyl)iminomethyl]phenol (2-MPIMP) and P-2-MPIMP were found to be between 75.29% and 48.17% at 1000 °C, respectively. P-2-MPIMP was shown to have a higher stability against thermal decomposition. Also, electrical conductivity of the P-2-MPIMP was measured, showing that the polymer is a typical semiconductor. Electrochemically, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and electrochemical energy gaps ( of 2-MPIMP and P-2-MPIMP were found to be −6.01, −6.03; −2.63, −2.82; 3.38 and 3.21 eV, respectively. According to UV-vis measurements, the optical band gap (E_g) of 2-MPIMP and P-2-MPIMP was found to be 3.40 and 2.97 eV, respectively.     

Synthesis, characterization and thermal degradation of oligo-2-[(4-fluorophenyl) imino methylene] phenol and some of its oligomer-metal complexes

In this study, the oxidative polycondensation reaction conditions of 2-[(4-fluorophenyl) imino methylene] phenol (FPIMP) with air oxygen and NaOCl were studied in an aqueous alkaline medium between 60 and 90 °C. Synthesized oligo-2-[(4-fluorophenyl) imino methylene] phenol was characterized by ¹H-NMR, FT-IR, UV-Vis, size exclusion chromatography (SEC) and elemental analysis techniques. The yield of oligo-2-[(4-fluorophenyl) imino methylene] phenol (OFPIMP) was found to be 62.00% (for air O₂ oxidant) and 97.70% (for NaOCl oxidant) at the optimum reaction conditions. According to the SEC analysis, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of OFPIMP were found to be 1370 g mol⁻¹, 1979 g mol⁻¹ and 1.45, using NaOCl, 2105 g mol⁻¹, 2557 g mol⁻¹, and 1.22, using air O₂, respectively. During the oxidative polycondensation reaction, (2.88%) a part of -CHN group oxidized to carboxylic acid (-COOH). TG and TG-DTA analyses were shown to be more stable of oligo-2-[(4-fluorophenyl) imino methylene] phenol and its oligomer metal complexes than monomer against thermo-oxidative decomposition. The weight loss of OFPIMP was found to be 97.00% at 900 °C. The weight losses of OFPIMP-Co, OFPIMP-Ni OFPIMP-Cu oligomer-metal complex compounds were found to be 88.66%, 94.36% and 83.21%, respectively, at 1000 °C.     

SYNTHESIS,CHARACTERIZATION,THERMAL DEGRADATION AND ELECTRICAL CONDUCTIVITY OF OLIGO[2-(THIEN-2-YL- METHYLENE)AMINOPHENOL] AND OLIGOMER-METAL COMPLEXES

The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ~(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ~(13)C-NMR data show that the polyme...     

Synthesis,characterization, thermal stability,conductivity, and band gaps of substitute oligo/polyamines or polyphenol

In this study, the oxidative polycondensation reaction conditions of 3,5‐dichloroaniline (DCA), 3,4,5‐trimethoxyaniline (TMA), 3,5‐bis(trifluoromethyl)aniline (BTFMA), and 4‐{[(3,5‐dichlorophenyl)imino]methyl}phenol (DCPIMP) were studied by using NaOCl oxidant in an aqueous alkaline medium between 40 and 90°C. The structures of the synthesized monomer and polymer were confirmed by FT‐IR, Ultraviolet–visible (UV–vis), ¹H‐NMR, and ¹³C‐NMR and elemental analysis. The characterization was made by TGA–DTA, size exclusion chromatography (SEC), and solubility tests. At the optimum reaction conditions, the yields of oligo‐3,5‐dichloroaniline (ODCA), poly‐3,4,5‐trimethoxy aniline (PTMA), oligo‐3,5‐bis(trifluoromethyl)aniline (OBTFMA), and poly‐4‐{[(3,5‐dichlorophenyl) imino]methyl} phenol (PDCPIMP) were found to be 98, 48, 80, and 83% in using NaOCl oxidant. According to the SEC analysis, the number‐average molecular weight (M_n), weight‐average molecular weight (M_w) and polydispersity index (PDI) values of ODCA, PTMA, and OBTFMA were found to be 2200, 3800 g mol^?1, and 1.727; 4700, 7500 g mol^?1, and 1.596; and 1690, 1950 g mol^?1, and 1.154, respectively. According to TG analysis, the weight losses of ODCA, PTMA, OBTFMA, and PDCPIMP were found to be 78.55, 54.18, 99.38, and 59.70% at 1000°C, respectively. PTMA showed higher stability against thermal decomposition. Electrical conductivity of the polymers was measured, showing that the polymer is a typical semiconductor. The highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and electrochemical band gaps ( ) of ODCA, PTMA, OBTFMA, and PDCPIMP were calculated from their absorption edges of cyclic voltammograms. The optical band gaps (E_g) values of all compounds were calculated from UV–vis measurements. Copyright © 2009 John Wiley & Sons, Ltd.     

Synthesis,Characterization and Thermal Degradation of Oligo‐2‐[(4‐hydroxyphenyl) Imino Methyl]‐1‐naphtol and Oligomer‐Metal Complexes

The oxidative polycondensation of 2‐[(4‐hydroxyphenyl) imino methyl]‐1‐naphtol (4‐HPIMN) has been accomplished by using NaOCl, H₂O₂ and air O₂ oxidants in aqueous alkaline medium. Optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established. At optimum reaction conditions, yield of the products were found to be 77.0%, 91.6% and 99.0% for H₂O₂, air O₂ and NaOCl oxidants, respectively. The structures of the obtained monomer and oligomer were confirmed by FT‐IR, UV‐Vis, ¹H‐ and ¹³C‐NMR and elemental analysis. The characterization was made by TG‐DTA, SEC and solubility tests. The ¹H‐ and ¹³C‐NMR data shows that the polymerization proceeded by the C–C coupling of ortho positions according to –OH group of 4‐HPIMN. The molecular weight distribution values of the product were determined by using size exclusion chromatography (SEC). The number‐average molecular weight (M_n), weight‐average molecular weight (M_w) and polydispersity index (PDI) values of O‐4‐HPIMN were found to be 1777, 2225 and 1.252; 1790, 2250 and 1.257; 4540, 5139 g mol^?1, and 1.132 for NaOCl, H₂O₂ and air O₂ oxidants, respectively. According to TG analyses, the carbonaceous residue of 4‐HPIMN and O‐4‐HPIMN was found to be 28.02% and 44.22% at 1000°C, respectively. Thermal analyses of O‐4‐HPIMN‐Cd, O‐4‐HPIMN‐Co, O‐4‐HPIMN‐Cu, O‐4‐HPIMN‐Fe, O‐4‐HPIMN‐Mg, O‐4‐HPIMN‐Mn, O‐4‐HPIMN‐Ni, O‐4‐HPIMN‐Pb and O‐4‐HPIMN‐Zn oligomer‐metal complex compounds were investigated in N₂ atmosphere between 15–1000°C.     

Synthesis,characterization, and optimum reaction conditions of oligo‐2‐[(pyridine‐2‐yl‐methylene) amino] phenol

The reaction conditions of the oxidative polycondensation of 2‐[(pyridine‐2‐yl‐methylene) amino] phenol (2‐PMAP) with air O₂, H₂O₂, and NaOCl were studied in an aqueous alkaline medium between 60 and 90 °C. Oligo‐2‐[(pyridine‐2‐yl‐methylene) amino] phenol (O‐2‐PMAP) was characterized with ¹H NMR, Fourier transform infrared, ultraviolet–visible, size exclusion chromatography (SEC), and elemental analysis techniques. Moreover, solubility testing of the oligomer was performed in polar and nonpolar organic solvents. With the NaOCl, H₂O₂, and air O₂ oxidants, the conversions of 2‐PMAP into O‐2‐PMAP were 98, 87, and 62%, respectively, in an aqueous alkaline medium. According to SEC, the number‐average molecular weight, weight‐average molecular weight, and polydispersity index of O‐2‐PMAP were 2262 g mol^?1, 2809 g mol^?1, and 1.24 with NaOCl, 3045 g mol^?1, 3861 g mol^?1, and 1.27 with air O₂, and 1427 g mol^?1, 1648 g mol^?1, and 1.16 with air H₂O₂, respectively. Also, thermogravimetric analysis showed that O‐2‐PMAP was stable against thermooxidative decomposition. The weight loss of O‐2‐PMAP was 96.68% at 900 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2717–2724, 2004     

SYNTHESIS, CHARACTERIZATION, THERMAL DEGRADATION AND ELECT-RICAL CONDUCTIVITY OF OLIGO[2-(2-HYDROXYPHENYLIMINOMETHYL-BENZYLIDENE)AMINOPHENOL] AND OLIGOMER-METAL COMPLEXES

The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between 50-90℃.The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established.At the optimum reaction conditions,yield of the products were found to be 67.72% and 61.49% for air O_2 and NaOCl oxidants respectively.The structures of the monom...     

Inverse isotope effects and electron-phonon coupling in the positively charged deutero- and fluoroacenes

Electron-phonon interactions in the monocations of deutero- and fluoroacenes are studied and compared with those in the monocations of acenes and those in the monoanions of fluoroacenes. Because of the significant phase pattern difference between the highest occupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbitals (LUMO), the frequency modes lower than 500 cm(-1) and the high-frequency modes around 1400 cm(-1) couple more strongly to the LUMO than to the HOMO, while the frequency modes around 500 cm(-1) and the frequency modes around 1600 cm(-1) couple more strongly to the HOMO than to the LUMO in fluoroacenes with D2h geometry. The total electron-phonon coupling constants for the monocations (l(HOMO)) are estimated and compared with those for the monoanions (l(LUMO)) in deutero- and fluoroacenes. The l(HOMO) values are estimated to be 0.418, 0.399, 0.301, 0.255, and 0.222 eV for C6F6 (1f), C10F8 (2f), C14F10 (3f), C18F12 (4f), and C22F14 (5f), respectively. The l(HOMO) values are smaller than the l(LUMO) values in small fluoroacenes. But the l(HOMO) value decreases with an increase in molecular size less rapidly than the l(LUMO) value in fluoroacenes, and the l(HOMO) value of 0.074 eV is much larger than the l(LUMO) value of 0.009 eV in polyfluoroacene. The logarithmically averaged phonon frequencies for the monocations (omega(ln,HOMO)) are estimated to be larger than those for the monoanions (omega(ln,LUMO)) in fluoroacenes. This is because the C-C stretching modes around 1600 cm(-1) couple most strongly to the HOMO, and those around 1400 cm(-1) couple the most strongly to the LUMO in fluoroacenes. The significant phase pattern difference between the HOMO and the LUMO is the main reason for the calculational results. The l(HOMO) values increase much more significantly by H-F substitution than by H-D substitution in acenes. The possible inverse isotope effects in the electron-phonon interactions as a consequence of deuteration in the monocations of nanosized molecules are suggested.     

Synthesis and characterization of oligo-4-[(pyridin-3-ylimino)methyl]phenol

The oxidative polycondensation of 4-[(pyridin-3-ylimino)methyl]phenol (4-PIMP) with O₂, H₂O₂, and NaOCl was studied in an aqueous alkaline medium between 50°C and 90°C. Oligo-4-[(pyridin-3-ylimino)methyl]phenol (O-4-PIMP) prepared was characterized by ¹H-NMR, ¹³C-NMR, FT-IR, UV-VIS, size-exclusion chromatography, and elemental and thermal analyses techniques. At the optimum reaction conditions, the yield of O-4-PIMP was 18.9%, 39.4%, and 46.8% using H₂O₂, O₂, and NaOCl oxidant, respectively. According to the TG analysis, the initial degradation temperature of O-4-PIMP was 218°C, which was by 50°C higher than that of 4-PIMP. Thermal analyses of 4-PIMP and O-4-PIMP were carried out in N₂ atmosphere at 15–1000°C. The highest occupied molecular orbital, the lowest unoccupied molecular orbital, and electrochemical energy gaps of 4-PIMP and O-4-PIMP were determined from the onset potentials for n-doping and p-doping, respectively. Also, optical band gaps of 4-PIMP and O-4-PIMP were determined according to UV-VIS measurements.     

Innenrücktitelbild: Developing Conjugated Polymers with High Electron Affinity by Replacing a C?C Unit with a B←N Unit (Angew. Chem. 12/2015)

The key parameters of conjugated polymers are lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Few approaches can simultaneously lower LUMO and HOMO energy levels of conjugated polymers to a large extent (>0.5 eV). Disclosed herein is a novel strategy to decrease both LUMO and HOMO energy levels of conjugated polymers by about 0.6 eV through replacement of a C C unit by a B←N unit. The replacement makes the resulting polymer transform from an electron donor into an electron acceptor, and is proven by fluorescence quenching experiments and the photovoltaic response. This work not only provides an effective approach to tune the LUMO/HOMO energy levels of conjugated polymers, but also uses organic boron chemistry as a new toolbox to develop conjugated polymers with high electron affinity for polymer optoelectronic devices.     

Developing Conjugated Polymers with High Electron Affinity by Replacing a CC Unit with a B←N Unit

The key parameters of conjugated polymers are lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Few approaches can simultaneously lower LUMO and HOMO energy levels of conjugated polymers to a large extent (>0.5 eV). Disclosed herein is a novel strategy to decrease both LUMO and HOMO energy levels of conjugated polymers by about 0.6 eV through replacement of a C? C unit by a B←N unit. The replacement makes the resulting polymer transform from an electron donor into an electron acceptor, and is proven by fluorescence quenching experiments and the photovoltaic response. This work not only provides an effective approach to tune the LUMO/HOMO energy levels of conjugated polymers, but also uses organic boron chemistry as a new toolbox to develop conjugated polymers with high electron affinity for polymer optoelectronic devices.     

Syntheses,electrochemical and spectroelectrochemical characterization of benzothiadiazole and benzoselenadiazole based random copolymers

Three novel donor-acceptor-donor type random copolymers based on benzothiadiazole (BTh) and benzoselenadiazole (BSe) were synthesized via Pd (0) catalyzed Suzuki polycondensation reaction. The two acceptor units were coupled with electron rich moieties which are carbazole (CZ), fluorene (FL) and silafluorene (SiFL). Monomers were characterized using ¹H and ¹³C-NMR spectroscopy. The number and weight average molecular weights of the polymers were calculated using gel permeation chromatography (GPC). All three polymers were electrochemically and spectroelectrochemically characterized. PBThBSeCZ, PBThBSeFL and PBThBSeSiFL showed only p-dopable character and their doping/dedoping potentials were determined as 1.4 V/1.2 V, 1.53 V/1.27 V and 1.8 V/1.3 V, respectively. Corresponding HOMO energy levels were calculated as ?5.85 eV, ?6.05 eV and ?6.15 eV whereas LUMO energy levels were found to be ?3.67 eV, ?3.84 eV and ?3.77 eV, respectively. PBThBSeCZ had lower HOMO level and band gap than PBThBSeFL and PBThBSeSiFL due to its increased electron donating capability of nitrogen atom in carbazole unit.     

Phthalocyanine‐Based Organometallic Nanocages: Properties and Gas Storage

Phthalocyanine (Pc) molecules are well‐known flexible structural units for 1D nanotubes and 2D nanosheets. First‐principles calculations combined with grand canonical Monte Carlo simulations are used to obtain the geometries, electronic structures, optical properties, and hydrogen‐storage capacities of nanocages consisting of six Pc molecules with six Mg or Ca atoms. The primitive Pc cage has T_h symmetry with twofold degeneracy in the highest occupied molecular orbital (HOMO), and threefold degeneracy in the lowest unoccupied molecular orbital (LUMO); the corresponding HOMO–LUMO gap is found to be 0.97 eV. The MgPc and CaPc cages have O_h symmetry with a HOMO–LUMO gap of 1.24 and 1.13 eV, respectively. Optical absorption spectra suggest that the Pc‐based cages can absorb infrared light, which is different from the visible‐light absorption in Pc molecules. We further show that the excess uptake of hydrogen on MgPc and CaPc cages at 298 K and 100 bar (1 bar=0.1 MPa) is about 3.49 and 4.74 wt %, respectively. The present study provides new insight into Pc‐based nanostructures with potential applications.     

Highly Pure Synthesis,Spectral Assignments,and Two‐Photon Properties of Cruciform Porphyrin Pentamers Fused with Benzene Units

Tetrameric porphyrin formation of 2‐hydroxymethylpyrrole fused with porphyrins through a bicyclo[2.2.2]octadiene unit gave bicyclo[2.2.2]octadiene‐fused porphyrin pentamers. Thermal conversion of the pentamers gave fully π‐conjugated cruciform porphyrin pentamers fused with benzene units in quantitative yields. UV/Vis spectra of fully π‐conjugated porphyrin pentamers showed one very strong Q absorption and were quite different from those of usual porphyrins. From TD‐DFT calculations, the HOMO level is 0.49 eV higher than the HOMO?1 level. The LUMO and LUMO+1 levels are very close and are lower by more than 0.27 eV than those of other unoccupied MOs. The strong Q absorption was interpreted as two mutually orthogonal single‐electron transitions (683 nm: 86 %, HOMO→LUMO; 680 nm: 86 %, HOMO→LUMO+1). The two‐photon absorption (TPA) cross section value (σ⁽²⁾) of the benzene‐fused porphyrin pentamer was estimated to be 3900 GM at 1500 nm, which is strongly correlated with a cruciform molecular structure with multidirectional π‐conjugation pathways.     

三嗪类双极性蓝色磷光主体材料的合成及性能

设计合成了一种基于三嗪类的新型双极性蓝色磷光主体材料[4-(4,6-二-α-萘氧基-1,3,5-三嗪-2-基)苯基]9-咔唑(NOTPC),并对其结构进行了表征。通过紫外-可见(UV-Vis)吸收、荧光、低温磷光、循环伏安法、热重分析(TGA)、差热分析(DSC)和密度泛函理论(DFT)对其性能及结构进行了研究。结果表明,NOTPC在CH₂Cl₂稀溶液中的吸收峰位于341和374 nm;发射峰位于478 nm;NOTPC的低温(77 K)磷光光谱的第一发射峰位于442 nm,其三线态能级为2.80 eV,与蓝色磷光材料FIrpic(2.62 eV)的能级相匹配;NOTPC的HOMO主要分布在苯基咔唑单元,而LUMO主要定域在三嗪环上。其HOMO能级为-5.40 eV,与阳极ITO的功函(-4.5~-5.0 eV)相匹配,LUMO能级为-2.32 eV,接近于电子传输材料PBD(-2.82 eV),NOTPC表现出双极传导性能, 且热稳定性良好。     

Rhodanine flanked indacenodithiophene as non-fullerene acceptor for efficient polymer solar cells

A fused-ring electron acceptor IDT-2BR1 based on indacenodithiophene core with hexyl side-chains flanked by benzothiadiazole rhodanine was designed and synthesized.In comparison with its counterpart with hexylphenyl side-chains(IDT-2BR),IDT-2BR1exhibits higher highest occupied molecular orbital(HOMO)energy but similar lowest unoccupied molecular orbital(LUMO)energy(IDT-2BR1:HOMO=-5.37eV,LUMO=-3.67eV;IDT-2BR:HOMO=-5.52eV,LUMO=-3.69eV),red-shifted absorption and narrower bandgap.IDT-2BR1 has higher electron mobility(2.2×10~(-3)cm~2 V~(-1)s~(-1))than IDT-2BR(3.4×10~(-4)cm~2 V~(-1)s~(-1))due to the reduced steric hindrance and ordered molecular packing.Fullerene-free organic solar cells based on PTB7-Th:IDT-2BRl yield power conversion efficiencies up to 8.7%,higher than that of PTB7-Th:IDT-2BR(7.7%),with a high open circuit voltage of0.95 V and good device stability.     

Tuning of the electronic properties of H‐passivated armchair graphene nanoribbons by mild border oxidation: Theoretical study on periodic models

We report the results of a DFT study of the electronic properties, intended as highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies, of periodic models of H‐passivated armchair graphene nanoribbons (a‐GNRs) as that synthetized by bottom‐up technique, functionalized by vicinal dialdehydic groups. This material can be obtained by border oxidation in mild and easy to control conditions with ¹Δ_g O₂ as we reported in our previous paper (Ghigo et al., ChemPhysChem 2015, 16, 3030). The calculations show that the two models of border oxidized a‐GNRs (model A, 0.98 nm and model B, 1.35 nm wide) present LUMO and HOMO energies lowered by an extend roughly linearly dependent on the amount of oxygen chemically bound. The frontier orbital energy variations dependence on the % wt of oxygen bound are, for model A: ?0.12 eV for the LUMO and ?0.05 eV for the HOMO; for model B: ?0.15 eV (HOMO) and ?0.06 eV (LUMO). © 2016 Wiley Periodicals, Inc.