In this work, polyaniline (PANI) and its doped state with microfiber morphologies were easily synthesized by a chemical route under the oxidative polymerization, in which the polymerization was performed in an acidic medium (protonic acids). In situ polymerization of aniline reacted with the chloride and sulfate ions of hydrochloric and sulfuric acid, respectively. The microfiber-like morphology of undoped and HCl doped PANI was observerd. The X-Ray diffraction patterns represented that H2SO4 doped PANI was crystalline in nature. The effects of dopant acids on its optical properties were discussed. The strong interaction between chloride and sulfate ions with the ammonium group of PANI has been explained. The microfiber and granular morphology for HCl and H2SO4 doped PANI were observed. The redshifts were observed for the microfiber nature of doped PANI. These analytical results confirmed that the prepared PANI was in the doped state. Further, we found that the prepared PANI can be used for the fabrication of polymer solar cells.

The efficiency and steadiness of solar cells are dependent on the experimental conditions during the fabrication of the device. In the present review, development in the last few decades in CdTe/CdS solar cells on different conducting substrates, their characterizations, and their effect on their performances has been illustrated. The variations in the efficiency were observed for the CdTe/CdS solar cells because of not only different deposition methods but also the difference in deposition conditions. In addition to this contact, material plays a significant role in the performance of a solar cell. CdTe/CdS solar cells with cheaper, greater efficiency can be possible soon.

In this work, highly conductive and transparent Al: ZnO (Al doped ZnO, i. e., AZO) thin films were grown by radio frequency (RF) magnetron sputtering technique at a typical deposition temperature. The effect of deposition temperature on the structural, morphological, optical and electrical properties was studied. The x-ray diffraction (XRD) studies revealed a hexagonal wurtzite crystal structure for all AZO layers with a (002) preferred orientation along the c-axis. Columnar, compact, uniform grain growth of the layer was observed from atomic force microscopy (AFM) images. The deposition temperature had an influence on the surface roughness and average grain size of deposited films, which could be confirmed by means of AFM images. Optical studies confirmed that both optical band gap energy and urbach energy were influenced by the substrate temperature. Highly transparent films with an energy band gap ranging from 3.48 to 3.65 eV were obtained upon changing the deposition temperature from 22 to 400. The presence of defects was confirmed by ℃ photoluminescence (PL) spectra. A systematic measurement of the electrical parameters like barrier height, and ideality factor of the devices (Ag/Al:ZnO) was carried out with the help of I-V characteristic. This study may be useful for the design and fabrication of AZO based electrodes for solar cell applications.

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Here we fabricated a novel mercurochrome (MC) sensitized ZnO/In2O3 photoanode based dye-sensitized solar cell (DSSC). The compact layer of ZnO was deposited on the substrate using a successive ionic layer adsorption and reaction (SILAR) method. Seed layers of ZnO/In2O3 were deposited by a simple and low-cost Doctor-blade method. Deposited bilayered photoanode was studied to develop a cost-effective alternative photoanode and enhance the performance of ZnO based DSSCs. MC dye was used as photosensitizers to sensitized ZnO/In2O3 photoanode. The obtained UV-Visible absorption spectra show that visible light absorption of the ZnO/In2O3 bilayer photoanode was more effective than bare ZnO and In2O3 photoanodes. The optical band gap was found to be 3.2, 2.87 and 2.95 eV for ZnO, In2O3, and ZnO/In2O3 bilayer, respectively. A photoconversion efficiency of about 0.51 % was achieved for MC sensitized ZnO/In2O3 bilayered photoanode based DSSC under 1 sun equivalent illumination. We confirm that ZnO/In2O3 bilayer photoanode based DSSCs show a better performance than single-layered ZnO and single-layered In2O3 based DSSCs.

Transparent and highly conducting amorphous and crystalline Al doped ZnO thin films were grown on glass substrate at room temperature by RF magnetron sputtering. The structural, electrical, morphological and optical properties of amorphous and crystalline Al doped ZnO thin films were studied. The XRD pattern revealed that the crystalline film corresponds to hexagonal wurtzite structure with (002) preferred orientation.-3 The minimum resistivity 4.2 x 10 Ωm was observed for crystalline film. The AFM and transmission spectra show that the average roughness of the crystalline film is higher than that of the amorphous film. Photoluminescence spectrum shows band to band transition in UV region and defect related transitions peaks in visible region. The deposited crystalline film shows low optical bandgap, 3.32 eV than amorphous film, 3.51 eV.

The energy demand is increasing with the development of science and technology, as even common people are accessible to use different home appliances, devices, and gadgets. Solar energy could be the only feasible solution to the present and future energy crisis. Amongst different types of solar cells, Dye-Sensitized Solar Cells (DSSCs) can cope up with the situation by providing cost effective and environmentally suitable solution. In the present work, we discuss the synthesis of Eosin-Y sensitized bi-layered ZnO nanoflower-CeO2 photoanode for DSSCs. The compact ZnO nanoflower-CeO2 layers were deposited by dip coatings and doctor blade methods respectively. From the XRD analyses, the structures of both ZnO and CeO2 were confirmed with the nanocrystalline size of ~15nm and ~10nm respectively by the Scherrer formula. SEM confirms the nanoflower morphology for ZnO (useful in dye adsorption and electron transfer) and porous, rough and spongy morphology for CeO2 (useful for dye adsorption). The band gap values of ~3.2eV and ~3.1eV for ZnO and CeO2 respectively were calculated using UV-Visible data by Tauc's plot. After device fabrication, form the J-V characteristics, the solar cell parameters for best-performing cells were calculated as open-circuit voltage ~460mV, short circuit photocurrent density ~0.4mA/cm 2 with fill factor ~55%.

In the present study, Dye-sensitized solar cells (DSSCs) were fabricated using novel 2-HNDBA dye. The effect of dye absorption time on the performance of DSSCs was studied. The Doctor Blade method was employed to prepare the ZnO seed layer. The structural, optical and morphological properties of the ZnO photoanode was studied systematically. The structure of ZnO was found to be hexagonal wurtzite structure of and has been confirmed through XRD. The 2-HNDBA sensitized Zinc Oxide based DSSCs have been studied for its photoresponse at the dye absorption time from 60-240 min. The fabricated DSSC prepread at 60 min dye absorbtion time was found to exibit at a fill factor and photo conversion efficiency of 0.44 and 1.09 % , respectively such that as the preparing time increases to 120 min, the respective parameters increases to 0.53 and 2.08 % at 120 min. However, on further increasing the dye absorbtion time the fill factor and photo conversion efficiency reduces to 0.51, 1.69%. Thus 120 min dye absorbtion time has been found to be optimized dye absorption time for novel 2-HNDBA dye-sensitized ZnO photoanode based DSSCs.