I. Lungu

• PhD
• Researcher at Moldova State University

This study presents the synthesis of tetracarboxy ZnPc/dextran and octacarboxy ZnPc/dextran solutions and the investigation of their photophysical properties using UV–vis, transient absorption (TA), and emission spectroscopy. Nanosecond TA measurements are conducted using pump–probe techniques. ZnPc(COOH)4 derivative exhibits efficient fluorescence...

In this study, a new metal oxide NP/MPc derivative composite as efficient photosensitizer for photodynamic therapy of cancer and photocatalytic activities is developed. The ZnPc(COOH)4/MgO composite consists of the synthesized water soluble tetra-carboxy zinc phthalocyanine derivative and magnesium oxide nanoparticles prepared with different precip...

This paper reports the conjugation of (MeIt)8ZnPcCl8 to silver nanoparticles (AgNPs) through a metal−ligand coordination system. From the spectral and photophysical studies, the Stokes shift, the excited state lifetime, and the quantum yield are estimated. It was observed that the conjugation of (MeIt)8ZnPcCl8 to AgNPs in DMSO/H2O solution led to a...

The influence of the technological conditions on the structure of ZnSe thin films deposited by the close-spaced sublimation method onto SnO2/glass and ITO/glass substrates was studied. The manufacturing parameters were optimized by varying substrate temperature. The X-ray diffraction analysis of the ZnSe thin films showed that films deposited at bo...

This paper describes the electrical and dielectric behavior of the nCdS/pZnTe HJ by current–voltage, capacitance–voltage characteristics, and impedance spectroscopy in a temperature interval 220–350 K. A microcrystalline p-ZnTe layer and n-CdS were grown on glass/ZnO substrate by closed space sublimation method. As frontal contact to CdS, the trans...

New photosensitizers based on tetracarboxy- and octacarboxy- ZnPc derivatives conjugated to natural polymers for photodynamic therapy (PDT) are proposed. The tetracarboxy- and octacarboxy- ZnPc powders prepared by the direct condensation and hydrolysis were conjugated to chitosan (Ch). The ZnPc(COOH)4 and ZnPc(COOH)8 powders were solubilized in DMS...

This paper presents the results of studying the photoelectric properties of CdSe/CdTe heterojunctions synthesized by the hot-wall epitaxy method. The CdSe/CdTe heterojunctions were manufactured by consecutive growth of CdSe and CdTe layers on a conductive ITO/glass substrate purchased from Solaronix Swiss. As ohmic contact for CdTe, Ni was deposite...

This paper describes the synthesis and characterization of a new water-soluble zinc aminomethylphthalocyanine: dextran copolymers for medical applications. Mono-ZnAMPc has been synthesized by the hydrolysis of mono-(carboxybenzamidomethyl) ZnPc in an acidic medium using a closed reaction system. Dextran has been modified with cyclic and acyclic car...

This paper focuses on the influence of the illumination of CdS/ZnTe solar cells with different ZnTe thin film thicknesses. The devices were analyzed through current-voltage measurements. The values of the open circuit voltage (VOC) and the short circuit current density (JSC) depend on the substrate and source temperatures. The JSC is observed to de...

Zinc telluride (ZnTe) thin films were prepared by close space sublimation method, and their detailed structural properties and wettability characterization were performed. The XRD analysis of all ZnTe thin films revealed the cubic structure, F-43m space group, regardless of the substrate and source temperatures. The vary of the substrate temperatur...

The paper describes the synthesis of polymer analogues of N-vinylpyrrolidone with acryloyl chloride functionalized with zinc phthalocyanine, by using the Friedel-Crafts method. The grafting of zinc phthalocyanine to Nvinylpyrrolidone copolymers was carried out at low temperatures (3-5 ⁰C), using the anhydrous AlCl3 catalyst. The purification of the...

This paper describes technological processes developed for less studied ZnTe thin films prepared by close space sublimation method, without an additional transport agent gas, for controlling their structural and optical properties. The enhanced oxygen incorporation depends on the source–substrate growth conditions. ZnTe thin films fabricated in the...

In this paper results of studying CdS/ZnTe heterostructures synthesized by the quasi-closed space sublimation method on glass substrates coated with an ITO layer are described. The electrical and photoelectric properties of the structures are studied using current–voltage and capacitance–voltage characteristics in a temperature range of 30–100 °C....

Low-temperature photoluminescence (PL) is used to study defects evolution via immersion technique and annealing in vacuum of ZnTe thin films. In this paper we studied how copper doping from solutions of different molar concentrations affects PL of ZnTe thin films grown by close space sublimation (CSS) method. Undoped ZnTe thin films showed PL emiss...

Zinc-tetracarboxy-phthalocyanine (ZnPc(COOH)4) was synthesized by a melting method and basic hydrolysis. A ZnPc(COOH)4/Fe3O4/Ch composite was prepared by immobilization of ZnPc(COOH)4 onto Fe3O4/chitosan nanoparticles by a simple immersion method. The photophysical properties were studied using UV-vis spectrophotometry, fluorescence spectroscopy an...

A solution processed ZnPc:PTDCI bulk heterojunction solar cells doped with iodine were fabricated and characterized. Photovoltaic properties of the solar cells were investigated by optical absorption, current densityvoltage characteristic and external quantum efficiency. The absorption of ZnPc:I2:PTDCI was observed in the (300-800) nm region. Solar...

In this study, the laser processing of thermally annealed TiO2 thin films at 420 ℃ in hydrogen atmosphere, utilizing an pulsed fourth-harmonic generation Nd: YAG laser employing different laser intensities in the atmosphere at room temperature, has been reported. Further, the surface morphology and crystalline structure have been investigated by me...

This paper focuses on the linking of zinc phthalocyanine (ZnPc) to N-vinylpyrrolidone (N-VP): acryloyl chloride (ClAC) copolymer. The synthesis of binary N-VP:ClAC copolymer was performed by the radical polymerization method and then grafted to ZnPc by the Friedel Crafts acylation reaction. We have developed a water-soluble ZnPc:ClAC:N-VP photosens...

Doped (with GaCl 3 ), undoped ZnO and ITO/ZnO:Ga nanostructured thin films are synthesized using the spray pyrolysis method. The doped ZnO thin films are synthesized at the atomic ratio of Ga/Zn added in the starting solution fixed at 1, 2, 3, and 5. Gallium-doped ZnO films synthesized on glass/ITO substrates are annealed at 450C in different envi...

Using a drop casting method, stronger absorbent and photosensitive composite thin films based on a copper-phthalocyanine (CuPc) oligomer and a poly (N-epoxypropylcarbazole) (PEPC) copolymer were developed. Morphology, structural behavior and optical properties of CuPc:PEPC composite thin films have been studied using scanning electron microscopy (S...

For the first time, in this work, we succeed in synthesizing in solution a novel supramolecular self-assembled zinc phthalocyanine (ZnPc) and N,N′-bis(3-pentyl)- perylene- 3,4,9,10-bis(dicarboximide) (bis-3-pentyl-PTCDI) system with improved light absorption and phosphorescence lifetime of the charge separated states up to 2.5 ms. Moreover, the str...

Undoped and Al-doped ZnO thin films have been prepared by spray pyrolysis in oxygen and argon atmospheres. The structural properties of ZnO thin films were investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). The optical properties were studied by UV-VIS spectroscopy and photoluminescence (PL) at room temperature. The elect...

Al-doped ZnO thin films have been prepared by spray pyrolysis, which facilitates the incorporation of a higher percentage of dopant atoms. The vacuum thermally annealed at 420 °C temperature thin films have been characterized by X-ray diffraction (XRD), optical spectroscopy. Electrical conductivity and the Hall effect are investigated in the temper...

The ZnO thin layers were grown on glass, InP and pInP-nCdS substrates from zinc acetate dissolved in water-acetic acid-methanol solution having a molarity of 0.2 M by using the spray method in the argon flow in the temperature range of (250–450) °C. The dependence of optical properties of ZnO layers on growth temperature have been investigated. The...

In fabricating CdS/CdTe photovoltaic devices by close space sublimation method, thermal annealed in CdCI2 ambient at 400 °C at the interface is deposited an i-CdO layer by magnetron sputtering. Comparative analysis of electrical, photovoltaic parameters and photo-response spectral distribution is studied. The insertion of i-CdO at the interface of...

The paper is dedicated to the synthesis and research of photosensitive polymeric materials from N-vinylcarbazole (N-VC) ternary copolymers with octyl methacrylate (OMA) or octa-1-ene (OC-1), then functionalized with zinc monohydroxyphthalocyanine (Zn-Pc-OH). Synthesis of the support copolymers was carried out by the method of radical polymerization...

Small photovoltaic modules are excellent supply source in the street light, traffic signalization et al. and can offer significant savings on both energy consumption and costs for cities. Polycrystalline CdTe PV cells fabricated at Moldova State University were proven to be the most favorable type for traffic light and street light systems, due to...