Sabit Horoz

Investigations of structural, optical, and photovoltaic properties of Fe-alloyed ZnS quantum dots

Pure ZnS and Fe-alloyed ZnS quantum dots (QDs) prepared by wet-chemical method at room temperature using mercaptoethanol as a capping agent. The nominal concentrations of Fe were 5, 10, and 15% weight of Fe. The QDs were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDAX), optical absorption and photoluminescence (PL) measurements. The cubic phase of pure and Fe-alloyed ZnS QDs was indicated using the XRD measurements. It was determined that the sizes of doped samples decrease as the Fe concentrations are increased. The band gaps of QDs were investigated using optical measurements. It was observed that the band gaps and the absorption windows of Fe-alloyed ZnS QDs increase with the increase in the concentrations of Fe. It was seen that as the concentration of Fe increases, both the absorption and the emission peaks of the alloyed ZnS QDs shift to shorter wavelength. The photovoltaic properties of Fe alloyed ZnS QDs have been investigated in this study for the first time. The pure ZnS and Fe-alloyed ZnS QDs were used to make quantum dots-sensitized solar cells. The performances of the solar cells, with the short circuit current density (JSC) and open circuit voltage (VOC) and incident photon to electron conversion efficiency (IPCE) of Fe-alloyed ZnS QDs increased with increasing Fe doping. Thus, Fe-alloyed ZnS QDs can be used as promising materials in solar cell technology due to fact that they have wider optical absorption spectrums.

Synthesis, structural, optical and photocatalytic properties of Fe-alloyed CdZnS nanoparticles

In this study, Fe-alloyed CdZnS nanoparticles (NPs) with 1% Fe concentration (Fe (1%): CdZn (2%)S) were synthesized by chemical precipitation at room temperature. The synthesized NPs were used as a catalyst for the decomposition of methylene blue under UV light. The obtained results showed that the photocatalytic activity of Fe (1%): CdZn (2%)S NPs was higher than that of CdZn (2%)S NPs. It was determined that the kinetics of the photocatalytic degradation of the methylene blue (MB) correspond to the pseudo-second order kinetics model. In addition to the photocatalytic properties, the structural, morphological and optical properties of Fe (1%): CdZn (2%)S NPs were investigated.

Photocatalytic degradation of methylene blue with Co alloyed CdZnS nanoparticles

In our present study, firstly; cadmium zinc sulfide (CdZnS) nanoparticles (NPs) with 1, 2, 5, 10% of Zn concentration were synthesized in aqueous solution by simple chemical co-precipitation method and their photocatalytic activity was investigated using the degradation of methylene blue under visible light in air at room temperature. It was found that CdZnS NPs with 2% of Zn concentration indicates the highest degradation efficiency compare to other Zn concentrations. CdZnS NPs with 2% of Zn concentration was symbolized as CdZnS_1. Later; 0.1, 0.2, 0.5, 1, 5, 10% of cobalt (Co) concentration was separately alloyed on the CdZnS_1 NPs. It was oberved that Co(5%):CdZnS NPs has the highest degradation efficiency. Structure, surface morphology, elemental analysis and optical properties of CdZnS_1 and Co (5%): CdZnS NPs 0were analyzed using X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray and UV–Vis absorption measurements, respectively. The results showed that Co doped CdZnS NPs can be employed as capable materials to ehance the photocatalytic activity.

Determination of the optimum Co concentration in Co:Sb 2 S 3 thin films

This current study consists of two phases. In the first step, PbS, Sb2S3:Co(0.25%), Sb2S3:Co(0.5%), Sb2S3:Co(0.75%) and Sb2S3:Co (1%) and Sb2S3:Co (2.5%) thin films were successfully synthesized on Zn2SnO4 coated on FTO conductive glasses using chemical bath deposition method at room temperature. The photovoltaic properties of the synthesized thin films were examined by applying both incident photon-to-current efficiency (IPCE) and current density (J)–voltage (V) measurements. It was observed that Co:Sb2S3 thin films with different Co concentrations have higher IPCE (%) and power conversion efficiency (η%) values higher than pure Sb2S3. Moreover, the Co concentration, which provides the best efficiency, was determined as 1% compared to other concentrations. In the second phase of the study; structural, elemental and optical properties of Sb2S3:Co (1%) thin film were investigated using X-ray diffraction, energy dispersive X-ray and optical absorption measurements, respectively. Consequently, it was clearly observed that the Co dopant affects particle size, energy band gap and power conversion efficiency of Sb2S3 thin films. In addition, our study suggests that Co:Sb2S3 thin films are promising materials that can be used in photovoltaic applications.

Investigation of structural, morphological, electronic and photovoltaic properties of Co(II) complex with ligand

The dye sensitized solar cells (DSSCs) used as an alternative to inorganic semiconductor sensitized solar cells (ISSCs), have favorable ecological and economical properties. In our current study, Co(II) complex with 4,4′-methylene bis (2,6-diethyl) aniline-3,5-di-tert-butylsalicylaldimine ligand was used as a sensitizer in DSSC by growing on TiO2 coated on FTO conductive glass substrate. Current density (J) versus voltage (V) measurement was applied to investigate the photovoltaic properties of the synthesized Co(II) complex with ligand. The calculated power conversion efficiency (η%) of the complex using the obtained current density (J) versus voltage (V) curve shows that this device can be used as a promising sensitizer in solar cell application. Furthermore, structural, morphological and electronic properties of Co(II) complex with ligand were characterized by x-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy and electronic absorption measurements, respectively.

Synthesis of Fe alloyed PbS thin films and investigation of their photovoltaic properties

Lead sulfide (PbS) and iron (Fe)-alloyed PbS thin films with different Fe concentrations were synthesized by chemical bath deposition (CBD) technique, which is suitable for cost on glass substrates at room temperature. The structural, elemental and optical properties of the synthesized thin films were characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX) and optical absorption measurements, respectively. It was observed that Fe dopant alters crystal size and energy band gap of PbS although it does not change the structure of PbS. PbS and Fe-alloyed PbS thin films with different Fe concentrations were grown on zinc tin oxide (Zn2SnO4) substrates coated on fluorine-alloyed tin oxide conductive glasses to investigate their photovoltaic properties. Incident photon-to-current efficiency (IPCE) and current density (J)–voltage (V) measurements were carried out to determine IPCE (%) and power conversion efficiency (η%) values of thin films. As a result, it was observed that as the concentration of Fe dopant is increased in Fe-alloyed PbS thin films, there is an increase in η%.

Synthesis of W(3%)-doped CdS thin film by SILAR and its characterization

In this study, the structural, elemental, optical and photovoltaic properties of W(3%)-doped CdS thin film on a glass substrate at room temperature using the low-cost successive ionic layer adsorption and reaction (SILAR) technique were investigated. Based on the obtained -ray diffraction patterns, it was determined that the structure of W(3%)-doped CdS thin film is cubic compared with the standard data. The spectrum obtained from energy dispersive X-ray analysis revealed that the doping process is successfully carried out by the SILAR method. The band gap (Eg) of W(3%)-doped CdS thin film was observed with both optical absorption and photoluminescence measurements, which were higher than the pure CdS. Finally, the photovoltaic properties of W(3%)-doped CdS thin film grown on TiO2 coated on the fluorine doped tin oxide conductive glass by SILAR method at room temperature were examined by both current density–voltage and incident photon to current efficiency measurements. Consequently, it can be seen from the application point of view that W(3%)-doped CdS thin film can be used as a promising sensitizer in thin film sensitized solar cells.

Characterization of La-alloyed CdS QDs synthesized by the successive ionic layer adsorption and reaction (SILAR) technique

In this present study, the photovoltaic, structural, elemental and optical properties of La-alloyed CdS quantum dots (QDs) synthesized at room temperature using the successive ionic layer adsorption and reaction (SILAR) technique were investigated for the first time. For La-alloyed CdS QDs with different La concentrations, incident photons to current efficiency (IPCE) was measured and the optimum La concentration giving the best solar cell efficiency was determined as 1%. Characterization procedures were then performed to determine the structural and optical properties of La-alloyed CdS QDs with 1% La. As a result, La-alloyed CdS QDs with 1% La have been proposed as promising materials for photovoltaic applications.

Synthesis, characterization and photovoltaic properties of Cd 1−x Zn x S and Mn: Cd 1−x Zn x S quantum dots

In our present study, firstly, Cd1−xZnxS (x = 0.25, 0.5, 1, 3 and 5%) quantum dots were synthesized at room temperature by the chemical precipitation technique. 1-thioglycerol was used as a capping agent to avoid any agglomeration. The incident photons to current efficiency measurements were carried out to determine Zn concentration in the Cd1−xZnxS quantum dots. Cd1−xZnxS (x = 3%) quantum dots showed the highest efficiency of quantum dot sensitized solar cells compare to other Zn concentrations. Secondly, after the determination of the optimum Zn content in the Cd1−xZnxS quantum dots, Mn (0.25, 0.5, 1, 3 and 5%): Cd1−xZnxS (x = 3%) quantum dots were synthesized at room temperature by same technique, then the incident photons to current efficiency measurements were performed to determine the optimum Mn concentration in the Mn (0.25, 0.5, 1, 3 and 5%): Cd1−xZnxS (x = 3%) quantum dots. It was found that Mn (3%): Cd1−xZnxS (x = 3%) quantum dots have the highest incident photons to current efficiency value compare to other Mn concentrations. Finally, structural, elemental and optical properties of Cd1−xZnxS (x = 3%) and Mn (3%): Cd1−xZnxS (x = 3%) quantum dots-have the highest incident photons to current efficiency value in their category-have been investigated. The effect of Mn on the photovoltaic properties of Mn (0.25, 0.5, 1, 3 and 5%): Cd1−xZnxS (x = 3%) quantum dots have been reported for the first time in this study and our study suggests that Mn (3%): Cd1−xZnxS (x = 3%) quantum dots can be used unique materials to enhance performance of quantum dot sensitized solar cells.

Synthesis and properties of Schiff base Fe(II) complex

ABSTRACT In our current study, Fe (II) complex with 4-4ʹ-methylene bis (2,6-diethyl)aniline-3,5-di-tert-butylsalisilaldimine (HL1) ligand was synthesized by chemical method and the synthesized Fe (II) complex with HL1 ligand was named as Fe(L1)2 complex. Structural, morphological, electronic absorption and photovoltaic properties of Fe(L1)2 complex were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, electronic absorption, and current density (J)–voltage (V) measurements, respectively. The obtained result from the J-V measurement shows that Fe(L1)2 complex synthesized by the chemical method can be used as a promising sensitizer for a dye-sensitized solar cell.