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CdO nanoparticles (CdO NPs) were synthesized utilizing urea-assisted auto-combustion (AC) and microwave combustion (MC) methods. The structural, thermal, optical, morphological, and compositional analysis of the prepared samples were investigated after they were heat treated at 350 °C. The impact of heat treatment and the method of synthesis on their physicochemical properties were investigated. XRD was used to determine the phase, crystallite size, and lattice constant of CdO NPs. The modification of the phase and crystallite size of CdO NPs indicates the impact of the heat treatment and synthesis process. The annealing process raises the crystallite size from 28 nm to 45 nm for the auto combustion approach and from 24 nm to 40 nm for the microwave combustion method. Under heat treatment, the energy band gaps of CdO NPs from auto combustion method and microwave combustion method samples were determined to be 2.09 eV and 1.65 eV, respectively. The surface morphology of CdO NPs was documented by SEM, indicating that the particle's morphology was modified by the synthesis procedure. The nanoscale range of the particles is confirmed by TEM micrographs of annealed CdO NPs, which is closely matched with the crystallite size derived from XRD. TG-DTA was used to examine the thermal characteristics of annealed CdO NPs.

Microwave synthesis method was adopted to prepare CdO nanoparticles using polyethylene glycol (PEG), NH3 and NaOH as a co-reagent. A systematic investigation by XRD, SEM, TEM and EDS has been undertaken to evaluate the role of co-reagents on the microstructural and morphological study of the metal oxide nanostructure obtained. The pH of the solution, determined by the co-reagent used, was the main parameter addressing the morphology of CdO nanostructures obtained. By using NH3 the growth of individual CdO particle is favored at the low pH of 9, likely due to low Cd supersaturation rate at this pH. On the other hand, the presence of NaOH as co-reagent increases pH to 11, enhancing Cd supersaturation and leading mainly to formation of nanowire aggregates. The optical and photoluminescence characteristics of the different CdO nanostructures synthesized have been also evaluated.

A new carbazole chromophore conjugated with substituted thiazolidine-4-one (CzPT) was synthesized by applying the Knoevenagel reaction between 3,6-diformyl-N-hexylcarbazole and ethyl 2-aceto-2-(5-oxo-3-phenylthiazolidin-2-ylidene)acetate. The chemical structure of the new derivative (CzPT) was elucidated by spectral studies. The CzPT absorption spectra in different solvents exhibited a red shift for λmax by increasing solvent polarity. Bands at 430-474 nm appeared and were attributed to intramolecular charge transfer with high π-π* characteristics. CzPT fluorescence spectra exhibited a red shift after increasing the solvent polarity. To understand the Stokes' shift ( ∆ν¯) behaviour of the CzPT derivative referring to the polarity of solvents, Lippert-Mataga and linear solvation-energy relationship (LSER) models were employed in which the LSER exhibited respectable results compared with Lippert-Mataga (r2 = 0.9707). Moreover, time-dependent density functional theory absorption spectra in hexane and dimethylformamide showed that λmax had a major contribution in the highest occupied molecular orbital to lowest unoccupied molecular orbital transition in both solvents. In addition, the reduced uniformity of crystal features may lead to dislocation or anomalous arrangement of crystals with irregular spacing, which automatically enhances the optical properties of such crystals.

The effect of illumination energy on the electrical parameters of a monocrystalline silicon solar module was investigated and results used to reveal the effective spectrum which can help in generating the optimum power and photovoltaic effect. The current-voltage (I-V) characteristics of the device were measured under different illumination energies. Results showed that the ideality factor (n), series resistance (Rs) and saturation current (Io) are mostly dependent on the illumination energy, while the shunt resistance (Rsh) and photocurrent (Iph) are illumination intensity-dependent. The increase in illumination energy led to decrease in the series resistance but increase in the saturation current and ideality factor. On the other hand, the increase in illumination intensity resulted in increasing the shunt resistance and open circuit voltage. The study is important to understand the effective solar spectrum in producing the optimum photovoltaic performance, which can be also useful to interpret the photodetectors and photodiodes response to a specific spectrum.

Synthesis for new Cu(II) complexes from acetamidopyridine derivitives and their characterization. Applying analytical, spectral and conformational techniques, the characterization for all new synthesizes, was achieved. Equimolar ratio (1:1) was proposed for all complexes in which the ligands behaved as bidentate toward copper center. The molar conductivity measurements defined state of acetate presence according to coordination sphere. Two structural forms were proposed for five complexes, square-planer and octahedral based on UV–Vis and ESR data. Conformational study was executed for all compounds by DFT method in Gaussian 09 under 6-31G basis set. The optimal structural forms were obtained besides other significant files (log, chk & fchk). Also, functional parameters were calculated, to put a well view about physical features. QSAR parameters were obtained from HyperChem program, also to assert on some characteristics. MOE-docking module, which considered the most powerful program simulates interaction of tested compound with biological systems, was also used to strengthen the study. The data extracted orient to great expectation for biological efficiency of complexes against breast cancer cells. The most shining point was the anticancer screening results, which reflect vigorous toxic behavior for most tested complexes against breast cancer cell line that actually exceeds than doxorubicin itself.

Novel copper complexes were prepared from acetanilide derivatives and deliberately characterized. The molar ratio obtained was 1:1 through neutral bi-dentate mode of bonding for ligands. Square-planer and distorted octahedral were the geometries proposed based on UV–Vis and EPR spectra. Isotropic and anisotropic parameters were estimated for well hyperfine splitting curves. Through applying crystal explorer 3.1 software package, Hirshfeld surface analysis was carried out. The dnorm as well as 2D fingerprint plots were demonstrated for molecule within crystal packing system. Conformational analysis was executed for all tested compounds. Frontier orbital patterns, iso-surface maps and ESP array plots were built upon optimized structures. QSAR parameters suggest the successful catalytic uses for new complexes, which may be evidenced for their calcination oxides. After calcination for complexes, the CuO was yielded and fully characterized. XRD patterns and SEM images signify the superior properties of the oxide obtained from Cu(II) to HL3 complex. Such oxide was used to synthesize biodiesel from suitable frying waste oils. Its physical features appeared match strongly with ASTM-D6751-02-standards (American Society for Testing and Materials) for detailed standards and specifications for biodiesel mixed with middle distilled fuels.

Divalent cobalt and copper chelates of the two ligands 1-(1-ethoxycarbonylmethyl-2-oxoindolin-3-ylidene) thiosemicarbazide (EOIT) and 1-(1-benzyl-2-oxoindolin-3-ylidene) thiosemicarbazide (BOIT) are the target compounds of the current study. Identification of the structures and geometries of these compounds have been performed using the possible physicochemical and analytical instruments. Elemental analysis, molar conductance and thermal analysis assured the composition of the four chelates to be [Co(BOIT)Cl]•1·.5H2O (BOIT-Co), [Cu(BOIT)Cl] (BOIT-Cu), [Co(EOIT)Cl2(H2O)]•5H2O (EOIT-Co) and [Cu(EOIT)Cl]•Cl (EOIT-Cu) which was further confirmed by the measurement of mass spectra. The architecture arrangement of the ligand atoms around Co and Cu centers has been determined depending on the UV–Vis spectral measurements and calculation of µeff values. This proved that the copper compounds were square planer whereas the cobalt complexes were tetrahedral or octahedral arrangements. These compounds were examined as corrosion inhibitors for Sabic iron in 1.0 M HCl solution using potentiodynamic polarization, electrochemical impedance spectroscopy, mass-loss and scanning electron microscopy techniques. The acquired outcomes disclosed that the examined compounds were found to have high inhibition efficiencies (% IEs) which were dependent on their concentrations and composition. The obtained high % IEs (83–87% at concentration of 400 mg/l) were interpreted by strong adsorption of the compounds’ molecules on the iron surface and such adsorption was discovered to follow Langmuir adsorption isotherm. At the same concentration, the % IEs are slightly increased in the order: EOIT-Cu > BOIT-Cu > EOIT-Co > BOIT-Co. Finally, the investigational results obtained from all employed techniques were in a good consistent with each other.

In this work, we presented experimental observation on solution-processed bulk heterojunction organic photodiode using vanadyl 2,11,20,29-tetra tert-butyl 2,3 naphthalocyanine (VTTBNc) as a p-type material. VTTBNc is blended with two different acceptors, which are PC61BM and PC71BM, to offer further understanding in evaluating the performance in organic photodiode (OPD). The blend film of VTTBNc:PC71BM with a volumetric ratio of 1:1 exhibits optimized performance in the VTTBNc blend structure with 2.31 × 109 Jones detectivity and 26.11 mA/W responsivity at a −1 V bias. The response and recovery time of VTTBNc:PC71BM were recorded as 241 ms and 310 ms, respectively. The light absorption measurement demonstrated that VTTBNc could extend the light absorption to the near-infrared (NIR) region. The detail of the enhancement of the performance by adding VTTBNc to the blend was further explained in the discussion section.

Simple preparation of flame-retardant, photoluminescent, and superhydrophobic smart nanocomposite coating was developed and applied onto cotton fibres using the simple pad-dry-cure technique. This novel strategy involved the immobilization of rare-earth-doped aluminium strontium oxide (ASO; SrAl2 O4 :Eu+2 ,Dy+3 ) nanoparticles, environmentally friendly room temperature vulcanizing silicone rubber (RTV) and environmentally friendly Exolet AP422 (Ex). The fabrics were also able to produce a char film in the fire-resistant assessment, providing fibres with a self-extinguishing characteristic. Furthermore, the fire-retardant performance of the coated cotton samples remained resistant to washing over 35 laundry cycles. The superhydrophobicity of the treated fabrics was monitored to improve by increasing the photoluminescent phosphor nanoparticles. The produced transparent photoluminescent film displayed an absorption at 360 nm and an emission at 526 nm. The photoluminescent fabrics were observed to generate different colorimetric shades, including white, green-yellow and bright white as monitored by Commission Internationale de l'Eclairage laboratory colorimetric coordinates. Slow emissions were detected for the treated cotton fabrics as monitored by emission, ultraviolet-visible light absorption, lifetime, and decay time spectral profiles to indicate glow in the dark phosphorescence effect. Both comfort and mechanical properties of the coated fibres were evaluated by measuring their bending length and air permeability.

Divalent cobalt and copper chelates of the two ligands 1-(1- Ethoxycarbonylmethyl-2-oxoindolin-3-ylidene) thiosemicarbazide (EOIT) and 1-(1-Benzyl-2-oxoindolin-3-ylidene) thiosemicarbazide (BOIT) are the target compounds of the current study. Identification of the constitution and geometry of these compounds have been performed using the possible physicochemical and analytical instruments. Elemental analysis, molar conductance and thermal analysis assured the composition of the four chelates to be [Co(POIT)Cl]•1.5H2O, [Cu(POIT)Cl], [Co(BOIT)Cl2(H2O)]•5H2O and [Cu(BOIT)Cl]•Cl which was further confirmed by the measurement of mass spectra. The architecture arrangement of the ligand atoms around Co and Cu centers has been determined depending on the UV-Vis spectral measurements and calculation of µeff values assuring the copper compounds to be square plane whereas the cobalt complexes have tetrahedral or octahedral arrangements. These compounds were examined as corrosion inhibitors for the Sabic steel in 1.0 M HCl utilizing potentiodynamic polarization, electrochemical impedance spectroscopy, mass-loss method and scanning electron microscopy at fixed temperature of 298 K. The acquired outcomes disclosed that the inhibition efficiencies (% IEs) of the examined compounds were set to be dependent on both the concentrations and composition of the compounds. The examined compounds were set to have high % IEs, which were interpreted by strong adsorption of the compounds’ molecules on the iron surface and such adsorption was discovered to follow Langmuir adsorption isotherm. The investigational results obtained from all utilized techniques were set to be in a good accord with each other.

This work reports on the performance of vertical organic field effect transistors (VOFETs) fabricated using two dissimilar dielectric materials, namely poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) and poly(vinylidene fluoride) (PVDF). A comparison of the devices shows that integrating P(VDF-TrFE) enables the VOFET to exhibit significantly higher current of 0.10 mA with mobility of 6.874 × 10−4 m2 V−1 s−1 as compared with PVDF, which has a current of 0.034 mA and mobility equal to 4.24 × 10−5 m2 V−1 s−1. VOFET fabricated with a P(VDF-TrFE) dielectric layer shows a high current, high mobility, substantial ON/OFF ratio and low threshold voltage. The obtained results demonstrate that the VOFET fabricated with P(VDF-TrFE) dielectric layer allows smooth current flow between electrodes and appreciably improves the device characteristics.

Two newly synthesized ligands based on 1,3,4-thiadiazolethiosemicarbazone have been isolated by the condensation reaction of 2,3-disubstituted-5-acetyl-1,3,4-thiadiazole derivatives with thiosemicarbazide in acidic medium in addition to their Co(II) chelates. The synthesized cobalt chelates that have been obtained by the reaction of each ligand with cobalt acetate were confirmed to have the formulae [(LM)Co(OAc)(H2O)2]H2O (LM–Co) and [(LN)Co(OAc)(H2O)2]0.5CH3OH (LN–Co); where LM and LN are 1,3,4-thiadiazolethiosemicarbazone ligands with methyl and nitro substituents, respectively. Comparison of the IR spectrum of each ligand with that of its cobalt complex implied that both ligands acted as monobasic tridentate connecting to the cobalt ion through N atoms of both azomethine group and thiadiazole ring and S atom of deprotonated SH group as well. The two complexes have been proved to have octahedral geometrical structures. The synthesized compounds were studied as corrosion inhibitors for carbon steel in molar hydrochloric acid solution using several chemical and electrochemical techniques. The investigational outcomes displayed that the inhibition efficiencies of the examined compounds were found to augment as the concentrations of such compounds raised. At comparable inhibitors concentration, the inhibition efficiency was a little increased following the order: LM > LM–Co > LN > LN–Co. The acquired high inhibition efficiencies of the explored compounds were ascribed to the potent adsorption of the molecules on the steel surface and construction of adherent layers. Such adsorption was found to accord with Langmuir adsorption isotherm. There is a good correlation in the results obtained from the different measurements used.

Two thiazole-based complexes were prepared from Co(II) and Cu(II) ions. The new ligand and its complexes were fully characterized by analytical and spectral techniques. The ligand behaved as a neutral tridentate in its keto-form towards the metals via O(8), O(10) and O(18) atoms. This was suggested based on the lower shift of υ(CH=O), υ(C=O)amide and υ(C-O) vibrations. The electronic transitions in Co(II)-HL and Cu(II)-HL complexes displayed d-d- transitions which belong to 4T1g→4A2g(F) & 4T1g(F)→4T1g (P) and 2Eg →2T2g, in the two complexes, respectively. ESR spectrum of Cu(II)-HL complex displayed g-factor by the following order; g//(2.1740)>g⊥(2.0935)>2.0023, which agrees with octahedral geometry. The geometry optimization was executed by DFT/B3LYP method under valence double zeta polarized basis set (6-31G*), to confirm the structural forms and the mode of bonding. The orientation and the charges of O(8), O(10) and O(18) atoms, support the coordination of the ligand in its keto-form with the metal ions. Pharmacophore profiles were obtained regarding thiazole ligand and other recommended drugs (arbidol, avigan and idoxuridine) that used in treatment protocol of COVID-19 pandemic. Also, query was run in MolPort-library to obtain antiviral analogues, to broaden the search for an effective treatment. Three analogues were obtained for arbidol, avigan and idoxuridine drugs, which have the following numbers; MolPort-047-605-644, MolPort-004-768-508 and MolPort-028-750-709, respectively. Moreover, molecular docking was carried out to obtain all interaction details and rank the efficiency of thiazole compound versus the three antivirals in their interaction with the two COVID-19 proteins. The outcomes suggested the significant antiviral activity of idoxuridine and thiazole (enol-form), which not reach to eliminate the pandemic exactly. While, arbidol and avigan did not have an effective antiviral role, although they still used in COVID-19 treatment protocol., graphical abstract Image, graphical abstract

The properties of nanomaterials generated by external stimuli are considered an innovative and promising replacement for the annihilation of bacterial infectious diseases. The present study demonstrates the possibility of getting the antibiotic-like drug action from our newly synthesized nanohybrid (NH), which consists of norfloxacin (NF) as the photosensitive material covalently attached to the ZnO nanoparticle (NP). The synthesized NH has been characterized using various microscopic and spectroscopic techniques. Steady state fluorescence and time-correlated single photon counting (TCSPC)-based spectroscopic studies demonstrate the efficient electron transfer from NF to ZnO. This enhances the reactive oxygen species (ROS) production capability of the system. First principles density functional theory has been calculated to gain insight into the charge separation mechanism. To explore the electron densities of the occupied and unoccupied levels of NH, we have verified the nature of the electronic structure. It is observed that there is a very high possibility of electron transfer from NF to ZnO in the NH system, which validates the experimental findings. Finally, the efficacy of NH compared to NF and ZnO has been estimated on the in vitro culture of E. coli bacteria. We have obtained a significant reduction in the bacterial viability by NH with respect to control in the presence of light. These results suggest that the synthesized NH could be a potential candidate in the new generation alternative antibacterial drugs. Overall, the study depicts a detailed physical insight for nanohybrid systems that can be beneficial for manifold application purposes.

Aminoguanidium-1-naphthoate and its Ni(II) and Co(II) complexes were synthesized and characterized by spectral, thermal and structural methods. By using these compounds as precursors, epoxy coated ligand, NiO and CoO has been prepared by Sol-gel method in order to protect the corrosion on mild steel substrate. Resistance and protection against corrosion of the synthesized sample was studied in 3 M HCl, 1.5 M H2SO4, and 0.5 M H3PO4 by weight loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The surface and structural morphological studies of epoxy-metal oxides were investigated using powder XRD and SEM analysis. The corrosion protection efficiency of epoxy -NiO and epoxy -CoO nanoparticles film on mild steel is high than epoxy-L. The molecular docking study against 3T88 and 1Y2T protein with synthesized compound was performed to study the interactions responsible for anti-bacterial activity against S. aureus and E. coli.

A novel structured of nanoporous vanadyl 2,11,20,29-Tetra Tert-Butyl 2,3 Naphthalocyanine (VTTBNc) films were prepared by template-assisted method. The structure and morphology of the fabricated VTTBNc nanostructures were studied by field emission scanning electron microscopy (FESEM) and micro-Raman spectroscopy. The VTTBNc nano-porous films showed a potential application in humidity sensors. 2017 Elsevier B.V. We would like to acknowledge University Malaya Research Grant (RP026C-15AFR) and Fundamental Research Grant Scheme (FP046-2015A) for project funding. Appendix A Scopus

In this letter, a p-type organic material from metal phthalocyanine (MPc) derivative, vanadyl 3,10,17,24-tetra-tert-butyl-1,8,15,22-tetrakis (dimethylamino)-29H,31H-phthalocyanine (VTP) has been utilized for fabrication of an organic electronic device. Prior to the fabrication of a vertical organic field effect transistor (VOFET), fundamental work in investigating the energy level of VTP has been done through determination of oxidation and reduction potentials. Energy levels of VTP were calculated based on the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of cyclic voltammetry (CV) and UV–vis analyses. Subsequently, the soluble VTP was employed as an active layer in VOFET with different thicknesses of 90.4 nm, 66.4 nm, and 52.1 nm. It is found that a device with 66.4 nm VTP’s thickness showed the optimum performance, by giving the maximum current density and lowest threshold voltage of around 37 mA/cm2 and 7.1 V, respectively. The effects of the channel thickness on the semi-transparent VOFET devices are explained in this work.

In the current study, for first time trivalent lanthanum (La) ions was incorporated with different loading into the 3D-sponge-like structured of TUD-1 mesoporous material. All fabricated materials were synthesized via applied one-pot sol-gel hydrothermal method. Different physical and chemical characterization techniques such as ICP, XRD, SEM, EDX, mapping, N2-sorption, DR-UV-Vis, HR-TEM, Raman and XPS were applied to characterize the synthetized materials. The prepared materials confirmed the formation of isolated active sites at low loading of lanthanum La+3 ions into TUD-1 silica matrix. On the another side, the nanoparticles of La2O3 with average size 10–50 nm of oxide crystals were found into the pores of TUD-1 at high loading of Lanthanum. The photoluminescence (PL) property of the synthetized samples were investigated under different excitation wavelengths ranged from UV to visible illumination. La-TUD-1 showed exhibited high emission PL spectra under the illumination of 346 nm, 380 nm, 470 nm, and 580 nm wavelength. The obtained PL emission bands are related to blue and green emission and hence can be employed as promised blue-green LEDs and biological labeling in different future application.

A direct and simple one-step procedure was applied to prepare gold (Au) nanoparticles (NPs) embedded in graphitic carbon nitride (g-C3N4) sheets. Four samples with different Au contents (from 0.5% to 5% wt) were prepared via thermal polymerization of melamine at 550 °C in the presence of commercial Au NPs after careful mixing using a ball mill. The prepared samples were characterized by XRD, DR-UV-Vis, Raman spectroscopy, XPS, SEM and HR-TEM. Characterization data confirmed the presence of zero-valent gold nanoparticles (Au0 NPs) on the g-C3N4 lattice without any chemical changes after the synthesis. The lattice constraints were found to vary with varying Au content; however, they were very close to those of the pure g-C3N4 sample. Moreover, as the Au content increased, the band gap calculation showed no significant shift, and the band gap did not change. The photocatalytic activity of the prepared samples was investigated in the decolourization reaction of Arsenazo III dye (ArIII) dye aqueous solution under visible light illumination (420

The use of organic materials has become an increasingly important issue in sensing devices in recent times. Phthalocyanine is among the most promising materials in this undertaking. Zinc phthalocyanine (ZnPc) based microporous device was fabricated and its capacitance was utilized as the sensing mechanism for a humidity sensor. The effect of the electrode gap of the device on the electrical properties was investigated along with the correlation between the device’s performances and the morphology of the sensing film. Using the solution-processed spin coating method, the capacitive type humidity sensor devices have been fabricated in a planar geometry of Al/ZnPc/Al with the presence of a microporous template. The size of electrode gaps measured with a surface profiler was 53.00 ± 0.06 μm, 119.00 ± 0.03 μm and 286.00 ± 0.01 μm. The surface morphology was characterized by using transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscopy (XPS). Analysis of the experimental results showed that the device with the shortest electrode gap (53.00 μm) produced the best sensitivity of 1.03 ± 0.04 pF/%RH than that of the longer gaps. Additionally, hysteresis as well as response and recovery performances have also been investigated.

A facile process has been employed to prepare the high quality ZnO nanostructures with different contents of Iron (Fe) doping. X-ray diffraction analysis confirms the synthesis of monophasic ZnO at all Fe contents and rules out the formation of secondary phase. The Scherrer formula was used to determine the particle size and noticed to be reduced from 23 nm to 9 nm when Fe doping increased from 0 to 7.5 wt%. Scanning electron microscopy study shows that the particle are of spherical shape and the size is reducing with Fe content. EDX/SEM elemental-mapping analysis confirm the synthesis of Fe doped ZnO, with homogeneous Fe distribution. A systematic reduction of energy gap was noticed from 3.287 to 3.212 eV. The photocatalytic activity of ZnO was systematically enhanced with Fe content and highest was noticed for 7.5 wt% Fe@ZnO SNPs and also degradation mechanism has been discussed.

Herein, we report a novel self-powered photodiode, which is based on all solution-processed active layer made of bulk heterojunction of TPD:Alq3. The photodiodes can be utilized for the detection of ultraviolet (UV) radiation in a self-powered mode without the need for an external power supply. The optimized photodiode with TPD:Alq3 (1:2) active layer presented a sensitivity, responsivity and detectivity of 1.76 × 103, 5.22 × 10−4 A/W and 3.11 × 1010 Jones, respectively at zero biased mode under 365 nm UV light. We proposed a new approach of utilizing impedance matching to deliver the maximum power of photodiodes to the external load. Nevertheless, with a tool of minimized impedance, one can nearly get the full functionality of the photodiode at zero biased volt, but with zero power delivery to the tool. The performance of TPD:Alq3 based photodiodes outperformed that of photodiodes reported in literature.

In the present study, p-type conducting polymer of poly [N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) has been explored for nanostructures. A novel approach has been adopted to transform nanorods into nanotubes by altering template-wetting methods. PCDTBT nanorods are fabricated by infiltrating porous alumina template with various solution concentrations of 5, 10 and 15 mg/ml. Upon thermal annealing PCDTBT beyond its melting point, the nanorods are transformed into nanotubes. The morphological and optical investigations reveal that the nanorods prepared with a concentration of 10 mg/ml are longer, denser, well-arranged and red shifted as compared to other nanorods. The PCDTBT nanotubes of the same concentration prepared at 300 °C are found the best among all other nanotubes with improved length, density and alignment as compared to their nanorod counterparts. Furthermore, the optical spectra of the nanotubes demonstrate broad spectral region, augmented absorption intensity and significant red-shift. The changes observed in Raman shift indicate improvement in molecular arrangement of the nanotubes. Optimization of the solution concentration and annealing temperature leads to improvement of PCDTBT nanostructures. PCDTBT nanotubes, with better molecular arrangement and broad optical spectrum, can be exploited in the state-of-the-art photovoltaic devices. Keywords: PCDTBT, Nanorods, Nanotubes, Template, Polymer melt

The effects of three tween compounds have been tested as corrosion inhibitors of a zinc surface in 0.1 M of sodium sulphate (Na2SO4) using potentiodynamic, potentiostatic transient in addition to the Electrochemical Impedance Spectroscopy (EIS) method. The efficiency of the inhibitory effect of these additives was found to decrease in the order: Tween-60 > Tween-80 > Tween-20. These compounds were selected based on their active surface property and high molecular weight as well as their solubility in aqueous media. Cyclic voltammetry (CV) was used to evaluate their effect on the ethanol oxidation. The experimental results were discussed and the correlation between the outcomes and inhibition properties towards Zn pitting corrosion was accomplished. Finally, quantum chemical descriptors of the tween derivatives that relate to their performance as regards corrosion inhibition efficiency have been determined and found to be in good agreement with the experimental results.

Gallium oxide (Ga 2 O 3 ) nanospheres were successfully synthesized via electron beam evaporation of gallium nitride (GaN) pellets on anodic aluminium oxide (AAO) template. Raman analysis proves the formed nanospheres were Ga 2 O 3 with all Raman peaks of the Ga 2 O 3 was present with very good intensities. FESEM analysis proves formation of the Ga 2 O 3 nanospheres on the surface of the alumina template with diameters of around ∼300 nm. Further annealing of the sample eliminates the presence of the nanospheres. Surface roughness analysis via the AFM proved smoother surface was achieved upon higher annealing temperature of 600 and 900 °C. In addition, FESEM analysis of the annealed sample at 600 °C indicates that the nanospheres were empty hollow spheres rather than full-filled nanospheres.

In this paper, composite micro-structures of Vanadyl 2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine) (VOPcPhO) and Poly (3-hexylthiophene-2,5-diyl) (P3HT) complex with nano-porous surface morphology have been developed by electro-spraying technique. The structural and morphological characteristics of the VOPcPhO:P3HT composite films have been studied by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The multidimensional VOPcPhO:P3HT micro-structures formed by electro-spraying with nano-porous surface morphology are very promising for the humidity sensors due to the pore sizes in the range of micro to nano-meters scale. The performance of the VOPcPhO:P3HT electro-sprayed sensor is superior in term of sensitivity, hysteresis and response/recovery times as compared to the spin-coated one. The electro-sprayed humidity sensor exhibits ∼3 times and 0.19 times lower hysteresis in capacitive and resistive mode, respectively, as compared to the spin-coated humidity sensor.

The ability to predict the weathering performance of the clearcoat system over a short period of time is essential for the design and development of coating production. Thus, the primary objective of the present study is to investigate whether it is possible to predict the weathering performance of an automotive paint system through determination of surface roughness, Ra, and micro-hardness before and after various weathering exposure times (0, 24, 168, 336, 504, 672 hours) and when employing two different detergent materials (house-use detergent and car wash detergent). The data were analysed using a pair-sample t-Test, with 0.05 level of significance. It was found that the total net of degradation in the clearcoat level during the first 24 hours was Ra ≈ 30.3 nm (for surface roughness) and 1.358 HV (for the μ-hardness) when using the house-use detergent. In contrast, it was found to be Ra ≈ 4.6 nm (for surface roughness) and 1.133 HV (for μ-hardness) when using the car wash detergent. Also, increased time of weathering (up to 672 hours) increases the Ra and μ-hardness values. It can therefore be concluded that the effect of house-use detergent was more severe than that of car wash detergent on the clearcoat system.

The present study demonstrates a novel nanoporous structure of aluminium 1,8,15,22-tetrakis 29H,31H phthalocyanine chloride (AlPcCl) prepared by template-assisted method for a humidity sensor. The nanoporous sensing layer was fabricated by solution wetting of anodic aluminium oxide template. The solutions of AlPcCl in different concentrations were spun cast over the template at various speeds. Both capacitive and resistive responses were measured as a function of different relative humidity levels. The sensor showed wide operating relative humidity range and responded at quite low humidity levels. Morphological changes were investigated by field emission scanning electron microscopy. The sensor showed wide operating relative humidity range. The sensor demonstrated better performance with improved sensing parameters, highlighting unique advantages of the low-molecular nanostructured sensing layer for the humidity sensors. We acknowledge the University of Malaya for project funding under the University Malaya Research Grant (RP026C-15AFR) and Ministry of Education Malaysia for project funding under the Fundamental Research Grant Scheme (FP046-2015A). This research was financially supported by Hibah Penelitian Dasar Unggulan Perguruan Tinggi No. 385/UN2.R3.1/HKP05.00/2018 from Ministry of Research, Technology and Higher Education Republic of Indonesia. Scopus

In this work, a broad investigation on the optical parameters of TPD:Alq3 composite thin films is reported. The films are prepared from different solution-processed mixtures and are deposited onto the quartz substrate in order to measure their optical response with UV–Vis–NIR spectrophotometer. Results showed that the non-dispersive refractive index and dielectric constant of TPD was increased from 1.49 to 1.75 and from 2.19 to 2.99 by Alq3 doping, respectively. The optical conductivity of TPD:Alq3 (1:3) composite was seen to be highly improved, reaching the value of 144 S/cm. The Wemple and DiDomenico (WD) model was used to find the band gap ( E g W D ) of the films and results were compared to those deduced from the Tauc's equation ( E g o p t ). It was found that the investigated films obey the single-oscillator model in defining the strength of the optical transitions.

The optoelectronics and spectroscopic properties of N, N-diphenyl-N, N-bis(3-methylphenyl)-1, 1-biphenyl-4.4 diamine: tris (8-hydroxyquinolinate) aluminum (TPD:Alq3) systems were investigated for the application of ultraviolet (UV) sensors. Solution processed spin coating technique was used to deposit the films on quartz and to fabricate the devices on ITO-integrated substrates. Results showed that UV absorption of TPD was improved by its doping with Alq3 acceptor in a 1:2 volumetric ratio, thereby reducing its energy gap from 3.08 eV to 2.95 eV. The electronic transition in TDP was found to be direct forbidden, but changed to direct allowed transition by Alq3 dopant. Larger photocurrent, increased exciton generation and improved UV sensing was achieved for TPD:Alq3 (1:2) based UV detectors compared to that of the TPD-based devices. The signal to noise ratio was increased when Alq3 content was added up to 1:2 volumetric ratio, while it was decreased when higher amount of Alq3 was added.

The (2 × 2) tunnels structured manganese dioxide nanorods with α phase (α-MnO 2 ) are synthesized via simplistic hydrothermal method at low temperature. The obtained tunnels structured α–MnO 2 nanorods are characterized by, Transmission electron microscopy, Scanning electron microscopy, and X-ray diffraction techniques. The oxygen reduction reaction (ORR) activity was studied by cyclic voltammetry and rotating ring-disc electrode voltammetry techniques in alkaline media. Moreover; the highly electrocatalytic tunnels structured α–MnO 2 nanorods were then also applied as cathode in rechargeable Li–O 2 cells. The Li–O 2 cells exhibited initial discharge capacity as high as ∼4000 mAh/g with the tunnels structured α–MnO 2 nanorods which was double the original capacity of the cells without any catalyst. Also we obtained 100% round trip efficiency upon cycling with limited capacity for more than 50 cycles.

Understanding the effects of enamel loss and surface softening caused by acidic soft drinks consumption would help in the clinical treatment of tooth wear and aid in the development of novel dental restorative materials. Hence, this investigation was car-ried out to examine the effects of “Miswak” on the acid eroded enamel surface at nano-mechanical scale. The first use of a stylus-based inductive gauge is introduced as means of measurement of acid attack on enamel surfaces and the effectiveness of aqueous extracts of Salvadora persica as dissolution inhibitors for acid eroded enamel surfaces. For pre-molar protective, after being exposed to aqueous extracts of Salva-dora persica solution, the performance of the enamel surface was improved by Ra ≈ 0.82 μm. Whereas, the surface was damaged after immersing in citric acid solution by Ra ≈ 0.63 μm. For pre-molar restoring, the enamel surface was degraded by Ra ≈ 0.34 μm when exposed to citric acid solution. While, the surface roughness was improved by Ra ≈ 0.95 μm when aqueous extracts of Salvadora persica solution was introduced. So, this study concludes that the aqueous extracts of Salvadora persica treatment work effectively on the eroded enamel surface.

In this study, the performance of organic-based photodetectors using poly(3-hexylthiophene) (P3HT) and o-xylenyl-C60-bisadduct (OXCBA) as the donor and acceptor material, respectively, is reported. Four different ratios of 1:0.25, 1:0.50, 1:1.00 and 1:1.50 of P3HT:OXCBA binary blended thin films are used as photoactive layers for organic photodetectors. Optimizing the ratio of photoactive layers dramatically enhances the performance of photodetectors, with rise and decay time of 445 and 309 ms, respectively, are recorded from 1:0.50 ratio. The responsivity of the optimized device is 252.69 mA/W while its specific detectivity is 1.85 × 101°Jones at −1 V, and has shown good stability for over 336 h. External quantum efficiency of 52.77 % and low surface roughness of 0.596 nm are obtained from the 1:0.50 P3HT:OXCBA device. These results imply a high detection potential of P3HT:OXCBA-based photodetector.

In current work, silver sulfide nanoparticles (Ag2S NPs) were prepared in presence of 0.0, 0.1, 0.25.0.5 and 1.0 g of sodium dodecyl sulfate surfactant (named as S1, S2, S3, S4 and S5) though a microwave assisted route within 10 min of irradiation at 700 W power. XRD established decent crystalline nature of the prepared Ag2S NPs of crystallite size in range from 44 to 49 nm. Scanning electron microscopy showed that the synthesized particles have three-dimensional irregular shape, very close to fused-spheres or worm-like structure. More importantly; the size of the particles is decreased with the amount of the applied SDS surfactant. Kubelka-Munk relation was used to evaluate energy gap and noticed ~1.014 for S1, 1.017 eV for S2, 1.021 eV for S3, 1.023 eV for S4, and 1.026 eV for S5 samples, i.e. the energy gap is slightly increase with the amount of the applied SDS surfactant. The estimated refractive index values are noted in 1.51–2.2 range. Dielectric constant (e1), loss tangent (tanδ) and dielectric loss (e2) were calculated and shows high values of e1 and low values of tanδ. The photocatalytic performance was examined in methyl green dye photocatalytic decolourization under illumination of UV/visible light. Ag2S samples exhibited excellent photocatalytic behavior, hence can be used in water treatment applications.

This work demonstrates the improvement in photo-current response of poly(3-hexylthiophene) (P3HT)-based thin film organic photodetector by introducing [6,6]-phenyl C71 butyric acid methyl-ester (PC71BM) as an acceptor in binary blended thin films and vanadyl 3,10,17,24-tetra-tert-butyl-1,8,15,22-tetrakis(dimethylamino)-29H,31H-phthalocyanine (VTP) as a complementary holes’ component in ternary blended thin films. The combination of these materials creates favorable energy levels that facilitates the transport of charge carriers from one material to another until it reaches at the respective electrodes. The increase in optical absorption across broader spectral range, the increase in interfacial area and the enhancement in electrical parameters were observed and discussed. In this study, device with ternary P3HT:PC71BM:VTP blended thin films with ratio of 1:1:1 shown the best photo-current response (at 1 V), in which the increase in short-circuit photocurrent density (Jsc) (6.0 mA/cm2) is 78% higher than that of P3HT:PC71BM:VTP with ratio of 1:1:2. The Jsc of ternary blended thin film device (1:1:1) is 5 times higher than that of single material device and it appeared to be 58% higher than that of binary P3HT:PC71BM devices. The increase electrical parameters indicated a significant enhancement in photo-current with the introduction of ternary blended thin films organic photodetector that constitutes of well-matched materials based on their individual optical, morphological and electrical properties.

Two novel thiosemicarbazone linked with 1,3,4-thiadiazole ligands were synthesized through the condensation reaction of the acetyl group at position 5 of 1,3,4-thiadiazole derivatives with thiosemicarbazide in acidic ethanol solution in addition to their Co(II)-complexes. The divalent cobalt complexes of both ligands have been synthesized through the reaction of cobalt acetate with each ligand leading to the formation of the two complexes [(LH)Co(OAc)]0.5H2O and [(LCl)Co(OAc) (H2O)2]; where LH and LCl are 1,3,4-thiadiazolethiosemicarbazone ligands. The two complexes have been proved to have tetrahedral and octahedral geometry from the results of UV–Vis spectra and magnetic moment. Analysis of the IR spectra of both ligands and complexes ascertained that the ligands behaved as monobasic tridentate coordinating to the metal ion center through azomethine-nitrogen atoms and thiadiazole ring in addition to deprotonated SH group. The synthesized ligands and their complexes were also investigated as inhibitors for the corrosion of carbon steel in 1.0 M HCl using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy and scanning electron microscopy techniques. The obtained results revealed that the inhibition efficiencies of the tested derivatives were found to depend on the concentrations and structures of such derivatives, and were decreased with raising temperature. At the same inhibitors concentration, the inhibition efficiencies are slightly increased in the order: LH > LCl > LH-Co > LCl-Co. The results derived from all applied techniques are harmonious with each other.

In this work, surface-type humidity sensors with P3HT (organic) and P3HT–TiO2 (organic–inorganic hybrid) active layers have been fabricated. The surface morphology of the humidity active films has been studied by atomic force microscopy, whereas their crystalline structure has been studied by X-ray diffraction. We have aimed at improving the sensing parameters of P3HT-based humidity sensor, by embedding nano-anatase TiO2 powder in pristine organic P3HT moiety. The capacitance versus relative humidity (%RH) response curves of the organic and hybrid humidity sensors have been examined in 30–98%RH range (dark ambient condition, room temperature). In general, an increase in capacitance has been observed in both sensors with the increment in RH level. The observed response of both humidity sensors is believed to be associated with polarization change due to the adsorption of water molecules and transfer of charge carriers due to the formation of charge transfer complexes. The hybrid-based humidity sensor has shown significantly improved humidity-sensing parameters, i.e., fivefold higher sensitivity, with hysteresis reduced to one-third as compared to that of pristine organic humidity sensor. A relatively faster response and recovery time has also been obtained by the hybrid sample.

In this work, Co/Cr nanoparticles-decorated carbon nanofibers were studied as a platinum-free catalyst for electrooxidation of ethanol in the alkaline medium. The investigated nano composites were prepared by simple, high yield and effective technique; electrospinning of cobalt acetate, chromium acetate and polyvinyl alcohol as a polymer precursor at 20 kV followed by calcination under inert atmosphere at 900 °C for 2 h. The suitable physicochemical characterizations such as XRD, SEM, TEM, TEM mapping, Line TEM-EDX and FE-SEM indicated the formation of pure CoCr nanoparticles allocated in/on carbon nanofibers. Electro catalytic activity measurements showed that the investigated Co–Cr carbon nanofibers can be effectively utilized in ethanol electrooxidation in 1 mol/l KOH solution. The observed current density was 105 mA/cm2 which is considered high value for non-precious electrocatalyst. Also, study the influence of Cr content in Cr–Co alloy toward ethanol oxidation was investigated to obtain the most effective composition. The suitable Cr concentration found to be 10% of Co content.

This research work demonstrates compositional engineering of an organic-inorganic hybrid nano-composites for modifying absolute threshold of humidity sensors. Vanadyl-2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO), an organic semiconductor, doped with Titanium-dioxide nanoparticles (TiO

This research work demonstrates compositional engineering of an organic-inorganic hybrid nano-composites for modifying absolute threshold of humidity sensors. Vanadyl-2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO), an organic semiconductor, doped with Titanium-dioxide nanoparticles (TiO2 NPs) has been employed to fabricate humidity sensors. The morphology of the VOPcPhO:TiO2 nano-composite films has been analyzed by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM). The sensors have been examined over a wide range of relative humidity i.e. 20-99% RH. The sensor with TiO2 (90 nm) shows reduced sensitivity-threshold and improved linearity. The VOPcPhO:TiO2 (90 nm) nano-composite film is comprised of uniformly distributed voids which makes the surface more favorable for adsorption of moisture content from environment. The VOPcPhO:TiO2 nano-composite based sensor demonstrates remarkable improvement in the sensing parameter when equated with VOPcPhO sensors. Scopus

In this study, low-bandgap polymer poly{[4,4-bis(2-ethylhexyl)-cyclopenta-(2,1-b;3,4-b′)dithiophen]-2,6-diyl-alt-(2,1,3-benzothiadiazole)−4,7-diyl} (PCPDTBT) nanostructures have been synthesized via a hard nanoporous alumina template of centrifugal process. Centrifuge has been used to infiltrate the PCPDTBT solution into the nanoporous alumina by varying the rotational speeds. The rotational speed of centrifuge is directly proportional to the infiltration force that penetrates into the nanochannels of the template. By varying the rotational speed of centrifuge, different types of PCPDTBT nanostructures are procured. Infiltration force created during the centrifugal process has been found a dominant factor in tuning the morphological, optical, and structural properties of PCPDTBT nanostructures. The field emission scanning electron microscopy (FESEM) images proved the formation of nanotubes and nanowires. The energy-dispersive X-ray spectroscope (EDX) analysis showed that the nanostructures were composed of PCPDTBT with complete dissolution of the template.

Oxidations of two aliphatic α-amino acids (AA), namely, leucine and isoleucine by hexachloroplatinate (IV) as an anticancer platinum (IV) complex has been studied using a spectrophotometric technique in perchlorate solutions in the presence of palladium (II) catalyst at a constant ionic strength of 1.0 mol dm-3 and at 25°C. The reactions did not proceed in the absence of the catalyst. The reactions of both amino acids showed a first order dependence on both [PtIV] and [PdII], and less than unit order dependences with respect to both [AA] and [H+]. Increasing ionic strength and dielectric constant of the reactions medium increased the rates of the reactions. A probable oxidations mechanism has been suggested and the rate law expression has been derived. Both spectral and kinetic evidences revealed formation of 1:1 intermediate complexes between AA and PdII before the rate-controlling step. The oxidation products of the investigated amino acids were identified as the corresponding aldehyde, ammonium ion and carbon dioxide. The activation parameters of the second order rate constants were evaluated and discussed