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In this work, easy and simple structured perovskite solar cells (PSCs) are designed and characterized. Our effort was to reduce the cost of the fabrication of such PSC devices, first by using an inexpensive starting precursor (aqueous methylamine solution) for the perovskite materials and second by design in a PSC structure free of the expensive hole transport layer (HTL). The CH3NH3PbI3 perovskite sols were deposited onto a conductive FTO glass using the spin coating technique followed by heating at 100 °C for 10 min. The structure of the films was characterized by X-ray diffraction (XRD) and their optical properties by UV–VIS spectrophotometry and photoluminescence (PL). The obtained phase confirmed the formation of a tetragonal perovskite structure. Two different solvents have been used, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The effect of the type and the concentration of the used solvent DMF and DMSO on the performance of the solar cells have been investigated. It was found that a 40% concentration of the perovskite material resulted in the optimum film thickness that gives the best photoelectric performance. The DMF-based PSC assembled solar cell exhibited the best performance with an open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2, and an overall photon to electric conversion efficiency of 5.7%; all these results are higher than those of cells made with DMSO. This work was supported financially partially by the PHC Al Maqdisi Grant No. 37038WF and the Palestinian German Joint Research Project PALGER2015-34-012. The authors would like to thank Mr. Ahmad Ashour for his assistance in UV–VIS measurements. In this work, easy and simple structured perovskite solar cells (PSCs) are designed and characterized. Our effort was to reduce the cost of the fabrication of such PSC devices, first by using an inexpensive starting precursor (aqueous methylamine solution) for the perovskite materials and second by design in a PSC structure free of the expensive hole transport layer (HTL). The CH3NH3PbI3 perovskite sols were deposited onto a conductive FTO glass using the spin coating technique followed by heating at 100 °C for 10 min. The structure of the films was characterized by X-ray diffraction (XRD) and their optical properties by UV–VIS spectrophotometry and photoluminescence (PL). The obtained phase confirmed the formation of a tetragonal perovskite structure. Two different solvents have been used, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The effect of the type and the concentration of the used solvent DMF and DMSO on the performance of the solar cells have been investigated. It was found that a 40% concentration of the perovskite material resulted in the optimum film thickness that gives the best photoelectric performance. The DMF-based PSC assembled solar cell exhibited the best performance with an open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2, and an overall photon to electric conversion efficiency of 5.7%; all these results are higher than those of cells made with DMSO.

ZnO nanoparticles (ZnONPs) were synthesized usinghydrothermal and sol-gel techniquesusing zinc acetate dihydrate (Zn (CH3COO)2.2H2O) as a row material and methanol as a solvent. The structural properties of ZnO NPs were studied using EDX, XRD, TEM, and the optical properties were characterized using UV-VIS and PL spectroscopies. The synthesized ZnO NPs showedhigh purity and revealed a wurtzite (hexagonal) crystal structure with particle size (D) ranged from25 nm to 28 nm. The UV-VIS absorption spectra of ZnO NPs samples and sensitizing dyes were performed.The obtained ZnO NPs exhibited the direct optical bandgap 3.15 eV. Dye-sensitized solar cells (DSSCs) were fabricated using synthesized ZnO NPsas a semiconducting layer, whichwas dyedwith different low cost dyes such as Eosin B (EB), Eosin Y (EY) and Rhodamine B (RB) that was used to sensitize the photoanode (ZnO NPs).The experimental results showed a significant efficiency for the fabricated DSSCs of synthesized ZnO NPs via sol gel technique comparing to hydrothermal technique. The EY dye exhibited the bestperformanceamong others, where a conversion efficiency showed a noteworthy improvement from 0.12 to 1.08 %. ZnO nanoparticles (ZnONPs) were synthesized usinghydrothermal and sol-gel techniquesusing zinc acetate dihydrate (Zn (CH3COO)2.2H2O) as a row material and methanol as a solvent. The structural properties of ZnO NPs were studied using EDX, XRD, TEM, and the optical properties were characterized using UV-VIS and PL spectroscopies. The synthesized ZnO NPs showedhigh purity and revealed a wurtzite (hexagonal) crystal structure with particle size (D) ranged from25 nm to 28 nm. The UV-VIS absorption spectra of ZnO NPs samples and sensitizing dyes were performed.The obtained ZnO NPs exhibited the direct optical bandgap 3.15 eV. Dye-sensitized solar cells (DSSCs) were fabricated using synthesized ZnO NPsas a semiconducting layer, whichwas dyedwith different low cost dyes such as Eosin B (EB), Eosin Y (EY) and Rhodamine B (RB) that was used to sensitize the photoanode (ZnO NPs).The experimental results showed a significant efficiency for the fabricated DSSCs of synthesized ZnO NPs via sol gel technique comparing to hydrothermal technique. The EY dye exhibited the bestperformanceamong others, where a conversion efficiency showed a noteworthy improvement from 0.12 to 1.08 %.

Condensation of 4-hydrazino-1,3-diphenylpyrazolo[3,4-d]-pyrimidine with the aldohexoses, namely, D-glucose, D-galactose, D-mannose and the aldopentoses, D-arabinose, D-xylose and D-ribose, by heating in an aqueous ethanol in the presence of a catalytic amount of HCl, gave the respective aldehydo-sugar hydrazones. Oxidative cyclisation of such hydrazones by stirring with iron(III) chloride in ethanol at room temperature afforded the expected acyclo C-nucleosides 3-substituted-7,9-diphenylpyrazolo[4,3-e][1,2,4]triazolo[4,3-c]-pyrimidines. The structures of the cyclised sugar hydrazones were confirmed by their elemental analyses and spectral data.

Three novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGFR قطر الخيرية Three novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGFR

The effect of nanoplasmonic (Ag) on the performance of DSSCs has been studied in doped and undoped ZnO (DZ and UZ) NPs, which were prepared by the urea-assisted combustion route. Different techniques were conducted to characterize DZ and UZ NPs. XRD patterns were indexed to the hexagonal wurtzite structure of ZnO NPs (ICSD-52362). The values of average crystalline size of UZ and DZ(1.0 mol% Ag) NPs were 20.45 and 22.30 nm, respectively. HR-TEM micrograph revealed good crystallization with an intermediate or poor agglomeration with distribution of semispherical morphologies of ZnO NPs. The energy bandgap of UZ and DZ NPs was changed from 3.21 to 3.31 eV. The deconvolution of the PL spectra recognized eight peaks into near ultraviolet (NUV) and visible regions. The PL emission of visible region overshadowed NUV transition. The photovoltaic cell with the doped photoanode DZ:1.0 mol% Ag exhibited the best performance parameters:Voc = 0.46 V, Jsc = 7.81 mA.cm-2, Pm = 1.91, FF = 51%, and η= 1.91%. A double exponential function was used as a powerful fitting function for the TOCVD data.The results revealed that τn in the UZ NPs photoanode was longer than that in theDZ:1.0 mol% Ag NPs photoanode. The authors would like to thank the Palestinian German Joint Research Project PALGER2015-34-012 and the PHC Al Maqdisi grant No. 37038WF for their partially financial support of this research. The authors would, also, like to thank Mr. Ahmad Ashour for his technical assistant The effect of nanoplasmonic (Ag) on the performance of DSSCs has been studied in doped and undoped ZnO (DZ and UZ) NPs, which were prepared by the urea-assisted combustion route. Different techniques were conducted to characterize DZ and UZ NPs. XRD patterns were indexed to the hexagonal wurtzite structure of ZnO NPs (ICSD-52362). The values of average crystalline size of UZ and DZ(1.0 mol% Ag) NPs were 20.45 and 22.30 nm, respectively. HR-TEM micrograph revealed good crystallization with an intermediate or poor agglomeration with distribution of semispherical morphologies of ZnO NPs. The energy bandgap of UZ and DZ NPs was changed from 3.21 to 3.31 eV. The deconvolution of the PL spectra recognized eight peaks into near ultraviolet (NUV) and visible regions. The PL emission of visible region overshadowed NUV transition. The photovoltaic cell with the doped photoanode DZ:1.0 mol% Ag exhibited the best performance parameters:Voc = 0.46 V, Jsc = 7.81 mA.cm-2, Pm = 1.91, FF = 51%, and η= 1.91%. A double exponential function was used as a powerful fitting function for the TOCVD data.The results revealed that τn in the UZ NPs photoanode was longer than that in theDZ:1.0 mol% Ag NPs photoanode.

Zinc oxide nanoparticles (ZnO NPs) were synthesized using a hydrothermal route. The prepared ZnO NPs were characterized by x-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), UV–vis spectroscopy, and photoluminescence (PL) spectroscopy. The XRD patterns confirmed the standard hexagonal wurtzite structure of ZnO NPs, and the calculated value of the average particle size was 23.34 nm. HR-TEM micrographs of ZnO NPs showed semispherical particle morphologies and their sizes lie between 10 and 40 nm. The estimated average size distribution of ZnO NPs was 21.35 6.01 nm. UV–vis spectrum of ZnO NPs revealed the highest absorption band at 360.5 nm, and the Eg was 3.70 0.01 eV. The PL spectrum emission was deconvoluted by eight peaks into two regions [near-ultraviolet (NUV) and visible that caused from the defects]. Two groups of dye-sensitized solar cells (DSSCs) thin film devices based on ZnO NPs were sensitized in different concentration solutions of 0.1, 0.32, and 0.5 mM of eosin B (EB) and eosin Y (EY) dyes. The sensitized DSSCs device with 0.32-mM dye of EY displayed higher efficiency and its performance parameters are much better among all other fabricated DSSCs devices. The short current density (Jsc) increased from 1.59 to 4:97 mA∕cm2 and the Voc enhanced from 0.36 to 0.46 V. The conversion efficiency from light to electricity showed a significant improvement from 0.29% to 0.94%. The transient open circuit photovoltage decay (TOCPVD) was measured to estimate the apparent electron lifetime or response time (τn) or the electron recombination rate (krec), using the double exponential function for first time to fit the experiment data of TOCPVD. The results revealed that the EY dye can be used as an efficient and an inexpensive dye for DSSCs. This research activity carried out between Gaza and Cairo-Egypt was financially supported by Qatar Charity IBHATH Project grant funded by the Gulf Cooperation Council for the Reconstruction of Gaza through the Islamic Development Bank. Zinc oxide nanoparticles (ZnO NPs) were synthesized using a hydrothermal route. The prepared ZnO NPs were characterized by x-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), UV–vis spectroscopy, and photoluminescence (PL) spectroscopy. The XRD patterns confirmed the standard hexagonal wurtzite structure of ZnO NPs, and the calculated value of the average particle size was 23.34 nm. HR-TEM micrographs of ZnO NPs showed semispherical particle morphologies and their sizes lie between 10 and 40 nm. The estimated average size distribution of ZnO NPs was 21.35 6.01 nm. UV–vis spectrum of ZnO NPs revealed the highest absorption band at 360.5 nm, and the Eg was 3.70 0.01 eV. The PL spectrum emission was deconvoluted by eight peaks into two regions [near-ultraviolet (NUV) and visible that caused from the defects]. Two groups of dye-sensitized solar cells (DSSCs) thin film devices based on ZnO NPs were sensitized in different concentration solutions of 0.1, 0.32, and 0.5 mM of eosin B (EB) and eosin Y (EY) dyes. The sensitized DSSCs device with 0.32-mM dye of EY displayed higher efficiency and its performance parameters are much better among all other fabricated DSSCs devices. The short current density (Jsc) increased from 1.59 to 4:97 mA∕cm2 and the Voc enhanced from 0.36 to 0.46 V. The conversion efficiency from light to electricity showed a significant improvement from 0.29% to 0.94%. The transient open circuit photovoltage decay (TOCPVD) was measured to estimate the apparent electron lifetime or response time (τn) or the electron recombination rate (krec), using the double exponential function for first time to fit the experiment data of TOCPVD. The results revealed that the EY dye can be used as an efficient and an inexpensive dye for DSSCs.

ZnO nanoparticles were synthesized using sol gel technique at differentcalcination temperature. The effect of calcination temperature on the structure and opticalproperties of ZnO NPs were studied in detail by using different techniques, X-raydiffraction, high-resolution transmission electron microscope, UV-VIS spectroscopy andphotoluminescence spectroscopy.X-ray diffractionanalysis revealed that the ZnO NPs werecrystalized in a wurtzite structure and the estimated average particle size increased from24.7 to40.4 nm with increasingcalcinationtemperature. In addition, the d spacingincreased from 0.28196 nm to 0.28213 nm.High-resolution transmission electronmicroscopy analysisimage showed spherical ZnONPs were formed. UV-VIS absorptionmeasurement was employed to evaluate the absorption edge and the optical band gapusingTauc plot. Energy gaprevealed a red shift from 3.15 to 2.96 eV when thecalcinationtemperaturewas increased. Dye sensitized solar cells were fabricated using synthesizedZnO NPs as a semiconducting layer that were dyed withdifferentXanthene(CH2[C6H4]2O)dyesseparately;(Eosin B, Eosin Y and Rhodamine B) which arelow costdyes. Thin layer of ZnO were deposited on transparentfluorine doped tin oxideconductiveglass using doctor blade method. Eosin Y exhibited the bestphotosensitizing. Theconversion efficiency showed a significant improvement from 0.1% to 1.08%. This research activity carried out between Gaza-Palestine and Cairo-Egypt, which was financially supported by Qatar Charity IBHATH Project grant funded by the Gulf Cooperation Council for the Reconstruction of Gaza through the Islamic Development Bank. ZnO nanoparticles were synthesized using sol gel technique at differentcalcination temperature. The effect of calcination temperature on the structure and opticalproperties of ZnO NPs were studied in detail by using different techniques, X-raydiffraction, high-resolution transmission electron microscope, UV-VIS spectroscopy andphotoluminescence spectroscopy.X-ray diffractionanalysis revealed that the ZnO NPs werecrystalized in a wurtzite structure and the estimated average particle size increased from24.7 to40.4 nm with increasingcalcinationtemperature. In addition, the d spacingincreased from 0.28196 nm to 0.28213 nm.High-resolution transmission electronmicroscopy analysisimage showed spherical ZnONPs were formed. UV-VIS absorptionmeasurement was employed to evaluate the absorption edge and the optical band gapusingTauc plot. Energy gaprevealed a red shift from 3.15 to 2.96 eV when thecalcinationtemperaturewas increased. Dye sensitized solar cells were fabricated using synthesizedZnO NPs as a semiconducting layer that were dyed withdifferentXanthene(CH2[C6H4]2O)dyesseparately;(Eosin B, Eosin Y and Rhodamine B) which arelow costdyes. Thin layer of ZnO were deposited on transparentfluorine doped tin oxideconductiveglass using doctor blade method. Eosin Y exhibited the bestphotosensitizing. Theconversion efficiency showed a significant improvement from 0.1% to 1.08%.

A new hybrid organic–inorganic material denoted by ZrPMP·1.7H2O, where PMP = N,N′-piperazinebis(methylenephosphonic acid), is prepared through the decomposition of zirconium fluoro-complex in the presence of PMP. This material is characterized by X-ray diffractometry, solid 31P NMR and FT-IR spectrophotometries and thermal analyses. All of the above mentioned analyses provide strong evidence that this material is structurally related to α-type layered zirconium phosphate.

A new series of 3-substituted-9-(1,1′-biphenyl-4-yl)-7-phenyl-7 H-pyrazolo[4,3- e][1,2,4]triazolo [4,3- c]pyrimidines and 2-substituted-9-(1,1′-biphenyl-4-yl)-7-phenyl-7 H-pyrazolo[4,3- e][1,2,4] triazolo[1,5- c]pyrimidines were synthesised, as a new class of potent xanthine oxidase inhibitors, by oxidative cyclisation of 4-[2-(arylidene)hydrazinyl]-3-(1,1-biphenyl-4-yl)-1-phenyl-1 H-pyrazolo[3,4- d]pyrimidines with FeCl3 in ethanol and Dimroth rearrangement.

A series of pyrazolo[4,3-e][1,2,4]triazolo[4,3-c]pyrimidines were prepared via oxidative cyclization of aldehyde N-(1,3-diphenylpyrazolo[3,4-d]pyrimidin-4-yl)hydrazones. Dimroth rearrangement of such a series yielded pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidines.

Two series of aldose N-(3-substituted-4-oxo-3,4-dihydroquinazolin-2-yl)hydrazones were prepared by the reaction of each of the aldoses with the appropriate 2-hydrazino-3-substituted-quinazolin-4(3H)-ones. Oxidative cyclisation of these aldose hydrazones with ferric chloride in ethanol yielded the title acyclo C-nucleosides.

A novel series of 2,4-disubstituted-1,2,4-triazolo[1,5-a]quinazolin-5(4H)-ones were prepared by Dimroth rearrangement of their respective isomers namely 1,4-disubstituted-[1,2,4]triazolo[4,3-a]-quinazolin-5(4H)-ones. The latter were prepared via new synthetic strategy based on 1,5-elecrocyclization of the respective N-(4-oxo-3-phenylquinazolin-2-yl)nitrilimines.

A series of pyrazolo[4,3-e][1,2,4]triazolo[4,3-c]pyrimidines were prepared via oxidative cyclization of aldehyde N-(1,3-diphenylpyrazolo[3,4-d]pyrimidin-4-yl)hydrazones. Dimroth rearrangement of such a series yielded pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidines.

Two series of aldose N-(3-substituted-4-oxo-3,4-dihydroquinazolin-2-yl)hydrazones were prepared by the reaction of each of the aldoses with the appropriate 2-hydrazino-3-substituted-quinazolin-4(3H)-ones. Oxidative cyclisation of these aldose hydrazones with ferric chloride in ethanol yielded the title acyclo C-nucleosides.

A novel series of 2,4-disubstituted-l,2,4-triazolo[l,5-a]-quinazolin-5(4H)-ones were prepared by Dimroth rearrangement of their respective isomers namely 1,4-disubstituted[1,2,4]triazolo[4,3-a]-quinazolin-5(4Η)-ones. The latter were prepared via new synthetic strategy based on 1,5-elecrocyclization of the respective N-(4-oxo-3-cyclohexylquinazolin-2-yl)nitrilimines.

A novel series of 2,4-disubstituted-l,2,4-triazolo[l,5-a]-quinazolin-5(4H)-ones were prepared by Dimroth rearrangement of their respective isomers namely 1,4-disubstituted[1,2,4]triazolo[4,3-a]-quinazolin-5(4Η)-ones. The latter were prepared via new synthetic strategy based on 1,5-elecrocyclization of the respective N-(4-oxo-3-cyclohexylquinazolin-2-yl)nitrilimines.

Two samples of manganese oxide nanoparticles (NPs) were synthesized by a simple solution-combustion method at ignited temperature 250 0C (C250) and 300 0C (C300). The structural and optical properties have been characterized by Xray diffraction (XRD), Fourier transform infrared spectrum (FTIR), UV-Vis absorption and Photo-luminescence (PL) spectroscopy. The XRD patterns of C300 showed a tetragonal hausmannite structure of Mn 3 O 4 NPs, where the XRD patterns of C250 revealed a mix phase structure of the manganese oxides NPs. The obtained PL emission illustrated two broad bands. The obtained FT-IR results coincided with the XRD results. The calculated average crystallite size (D) was 27 and 26 nm for C250 and C300, respectively. The electrochemical performance of the prepared electrodes based on the synthesized samples C250 and C300 were examined in 1 M NaSO 4 electrolyte solution using cyclic voltammetry. The examined electrodes based on sample C250 presented a relatively large specific capacitance 128 F.g−1. As a result, manganese oxide NPs could be a promising candidate to be used as an electrode material for supercapacitors.