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We report the synthesis, characterization and effect of infusion of aluminium plasmons (Al3+) into titania/zinc oxide (TiO2/Al@ZnO or TAZ) nanocomposite photoanode on the efficiency of novel plasmonic Dye-Sensitized Solar Cells (DSSCs). On comparison with bare titania/zinc oxide (TiO2/ZnO or TZ) nanocomposite, plasmonic TAZ exhibits a negligible change in crystallographic and morphological properties, whereas the photoconduction and light harvesting capability are significantly enhanced. Prompted by surface plasmon modes, TAZ exhibits strong emissions in the blue-yellow region of visible spectrum, as observed with photoluminescence (PL) study. Owing to plasmon-induced PL, light enhancement takes place within the photoanode. Therefore, photoconductivity of TAZ is observed to be 4 folds higher than that of TZ. The narrowing of bandgap upon Al3+ infusion is confirmed by Kubelka-Munk plot and cyclic voltammetry. Specifically, we also focused on the architecture of novel DSSCs with silver counter electrode via a facile preparation method for the first time. Blending the advantages of nanocomposite, surface plasmon resonance and bandgap narrowing, the multifaceted TAZ features with short-circuit current density JSC ~ 33 mA cm−2, open-circuit voltage VOC ~ 0.41 V, Fill-factor FF ~ 0.81 and a remarkable efficiency of 11.4%, which opens up the opportunity to optimize and design a new class of next generation plasmonic DSSCs.

This article summarises the design of one dimensional Titanium dioxide (TiO2) nanorod array and its compatibility as Electron Transport Medium (ETM) for Solar Cell Application. The approach followed for the growth of the one-dimensional nanostructures was template-free, one-step hydrothermal synthesis which is convenient for commercialization. A series of microscopic characterisation such as XRD, SEM and EDAX were carried out to analyse the structure and morphology of the prepared TiO2 array. The optical properties were determined using UV-DRS analysis. Field dependent dark and photoconductivity studies showed positive response confirming the effective photo conducting nature of the as-prepared samples. As a result, all these features validate the usage of one dimensional titanium dioxide array as efficient ETM in the fabrication of Solid State solar cells.

We present a detailed examination on the microstructural, structural, optical and electrical properties of one dimensional (1D) and three dimensional (3D) titania nanostructures in comparison with zero dimensional (0D) titania nanoparticles. Material characterization by X-ray Diffraction technique confirms the formation of anatase phased TiO2 nanoparticles and rutile phased nanorods and nanoflowers. Morphological investigations were done with Field Emission Scanning Electron Microscopy and High Resolution Transmission Electron Microscopy. Optical properties of the samples were studied using UV-Visible Diffuse Reflectance Spectroscopy and their optical band gap energies were calculated using Kubelka-Monk method. Although the 1D nanorods possess faster electron transport than the nanoparticle structure, their low surface area has detained that morphology to absorb more incident radiation. However, the 3D nanoflower morphology coupled with excellent light scattering capability and enhanced optical absorption resulted in a 7 fold increase in dark and 26 fold increase in photocurrents compared to nanorod and nanoparticles. Dye Sensitized Solar Cells (DSSCs) are developed using Safranine O dye and their I-V characteristics were examined. Improved performance of DSSC is observed in the case 3D nanoflower structures delivering efficiency of about 3.56 %. The findings of this work essentially suggest that the optical transport properties of the photoanode materials and therefore cell performances are significantly influenced by their respective morphologies.

We report herein a relative analysis of plasmon (Al) impregnated SnO2/TiO2 and ZnO/TiO2 nanocomposite systems synthesized using sol-gel method. The properties of the Al-SnO2/TiO2 and Al-ZnO/TiO2 have been studied using various characterisation techniques such as XRD, EDAX, FESEM, UV-DRS, and Photoconductivity techniques. The elemental composition and phase structures of the as-synthesized Al-SnO2/TiO2 and Al-ZnO/TiO2 nanocomposites were investigated using Energy Dispersive X-Ray (EDAX) and X-Ray Diffraction (XRD), which showed high degree of purity and crystallinity respectively. The crystallite sizes estimated with Scherrer’s formula were about 24 and 22 nm respectively. The FESEM images revealed that, both the samples were mesoporous in nature. The optical properties of both Al-SnO2/TiO2 and Al-ZnO/TiO2 samples exhibited strong absorption and diffused reflectance which suggested the possibility of the samples being used as photoelectrodes and the band gap value was found to be 3.38 eV and 3.07 eV using Kubelka-Munk plot. The photoconductivity studies suggested that Al-SnO2/TiO2 showed higher photo current values in reference to the Al-ZnO/TiO2 nanocomposite. Upon overall comparison, it is concluded that the Al doped SnO2/TiO2 exhibited enhanced characteristics over that of Al-ZnO/TiO2 nanocomposite and hence could be applied as efficient photoelectrodes for DSSCs.

Nanomaterials when developed as thin films exhibit better properties compared to nanoparticles. Tin oxide with its outstanding properties such as wide band gap, low electrical resistivity, and good chemical stability is a versatile material in the field of nanomaterials. Metal doped SnO2 in addition exhibits enhanced properties. We report herein the preparation and analysis of the important properties of Al doped and pure SnO2 thin films through a simple sol-gel process and subsequent spin coating on FTO substrates. Microstructural characterization of the thin films was carried out for comparative evaluation of their physical properties. The as-grown thin films were studied using powder XRD technique and the crystallite sizes were estimated for Al doped and bare SnO2 thin films. The surface morphologies of the as-synthesized thin films were examined using High Resolution Scanning Electron Microscope. The observed images indicated lesser agglomeration and good homogeneity in the case of Al doped SnO2 thin films in comparison with its pure counterpart. The surface area, pore volume and pore radius of the samples were determined using BET analysis. The Fourier Transform Infrared Spectroscopy evidenced the presence of the various functional groups related to the materials of the films.

This analytical study highlights the effects of dimensional modulations on the characteristic properties of anodically grown Titania nanotubes. Titania nanotubes were grown using electrochemical anodization method employing a two-electrode system. The as-grown nanotubes with different dimensions were characterized in order to study their structural, electrical and optical properties. The investigation reveals that the impact of dimension was pivotal in tuning the band gap of these anodically grown Titania nanotubes which asserts its successful application in various fields. The desired dimensional modulation of the nanotubes was achieved by changing the corresponding anodising voltage. This study also employs a remedial two step anodization technique in addition to the conventional one step method and presents its distinctive edge over the other as established by various characterisation techniques. The comparative variations in the structural and crystallite dimensions of the Titania nanotubes anodised by two different methods were investigated by Field Emission Scanning Electron Microscopy and X-Ray Diffraction spectroscopy respectively, while the band gap tuning ability as well as absorption characteristics were determined by UV-Diffuse Reflectance spectroscopy. Finally, the effective changes in the band gap were corroborated by analysing the field effect dark and photo-conductive nature of the two materials.

The present work reports the synthesis of Titania/Zinc Oxide (TiO2/ZnO) nanocomposite and improvisation of its optical properties through Aluminium (Al) plasmon impregnation into ZnO using sol-gel technique. The X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) analysis showed that Al impregnation has not altered the crystallographic and morphological features of TiO2/ZnO. UV–Vis Diffuse Reflectance Spectroscopy (UV-DRS) revealed the enhanced light harvesting capabilities of Titania/Al impregnated Zinc Oxide (TiO2/Al-ZnO) as a result of about 95% of diffused reflectance, the highest reported to-date. Field dependent dark and photocurrent measurements showed that impacted by the plasmonic-effect, the photo and dark current values of TiO2/Al-ZnO are higher than those of TiO2/ZnO by ∼2 and ∼1.5 folds respectively. Owing to the improved photo and electrical conductive properties of the nanocomposite due to Al impregnation, the as-prepared TiO2/Al-ZnO nanocomposite qualifies as a novel and suitable candidate for application as a proficient photoanode in Dye Sensitized Solar Cells (DSSCs).

A method of electroplating a platinum-rhodium (Pt-Rh) alloy coating with a specified composition on a metal substrate stainless steel (SS304) is presented in this article. The Pt-Rh bath consists of [Pt (NH3)2]HPO4, H2SO4 and Rh2(SO4)3. The Pt-Rh alloy electrodeposition coatings were characterized by different analytical methods such as Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). SEM images justify that coating is uniform in a 75%duty cycle. Energy Dispersive X-Ray Spectroscopy (EDX) confirms the presence of Pt and Rh in the coating. XRD confirms that crystalline size was reduced from 75% duty cycle to the rest of the PC’s coatings and DC (Direct current).The incorporation of the Pt-Rh metal ions was verified by EDX analyses. The corrosion behaviour of the developed Pt-Rh alloy coatings was evaluated in 0.1M Na2SO4 solution using potentiodynamic polarization and electrochemical impedance techniques. The coating developed at PC-75% duty cycle possesses the highest corrosion resistance. A photocatalytic degradation study of Pt-Rh coating was conducted for Methylene Blue (MB) dyes under UV light radiation. The dye removal efficiency of Pt-Rh coated samples was 97% after irradiation and PC 75% duty cycles showed an exceptional dye degradation percentage compare to the DC coating source. All photocatalytic behaviour was controlled by using a UV–Vis spectrophotometer.

Zn–Ni–CNT composite coatings were prepared by electrodeposition from a sulphate bath. The effect of CNTs on the corrosion behavior, wear resistance and hardness of the composite coatings was investigated. Their corrosion properties were evaluated by polarization, impedance, weight loss and salt spray tests. The CNT particles inclusion improved the corrosion resistance, hardness and wear resistance of the coating. The grain size of the composite coating was smaller than that of a pure Zn–Ni coating with the same Zn/Ni ratio. Scanning electron microscope images and X-ray diffraction patterns of coating revealed its fine-grain nature.

The corrosion inhibition effect of 3-[(E)-(phenylimino)methyl]quinoline-2-thione (PMQT), 3{(E)-[(4-chlorophenyl)imino]methyl}quinoline-2-thione (CPMQT) and 3{(E)-[(4-fluorophenyl)imino]methyl}quinoline-2-thione (FPMQT) on mild steel in 1 mol dm −3 HCl has been determined by mass loss, polarization and impedance (EIS) methods at 300 K. The investigated results showed that the corrosion rate decreased significantly with increase in the concentration of inhibitors. The shape of polarization profiles of all the three compounds indicated their mixed-type nature of inhibition. The inhibition efficiencies decreased in the order FPMQT > CPMQT > PMQT. The adsorption of the compounds on the mild steel surface obeys Langmuir's adsorption isotherm. The surface morphology of the tested mild steel specimens in the presence and absence of inhibitors was studied by using the respective images of SEM. FTIR studies were undertaken to confirm the interaction of molecules with surface atoms of the mild steel and established the adsorption process.

Zn–carbon nanotubes composite coatings were obtained from a sulphate bath containing dispersed carbon nanotubes (CNTs). The electrochemical and weight loss measurements were made to find the corrosion behavior of composite coating. The presence of carbon nanotubes shifts the potential of zinc deposit to more positive values. The composite coatings were porous free and the service life of coating was examined by salt spray test. The electrochemical studies revealed higher resistance of composite coatings to corrosion. The surface morphology was investigated by recording the SEM images of coating before and after corrosion. The mechanism of action against corrosion was established.

Aspirin was investigated as a good corrosion inhibitor for mild steel in 1 M hydrochloric acid at a temperature region from 303 to 333 K. The computed inhibition efficiency increases by increasing the inhibitor concentration and decreases by increasing the temperature. The investigation was done by weight loss, electrochemical measurements such as Tafel polarization and electrochemical impedance spectroscopy. Inhibition effect is attributed to the adsorption of inhibitor on the surface of the mild steel. The Tafel method reveals that the Aspirin acts as a mixed type inhibitor. Activation parameters suggest that the adsorption process is exothermic in nature. SEM photographs of mild steel in the absence and presence of inhibitor visualize the adsorption layer on the surface of the mild steel.