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Nanostructured thin films of metal sulfides (MS) are highly desirable materials for various optoelectronic device applications. However, a general low-temperature protocol that describes deposition of varieties of MS structures, especially in their film form is still not available in literatures. Here, a simple and highly effective general solution-based deposition protocol for highly crystalline and well-defined nanostructured MS thin films from ethanol on variety of conducting and non-conducting substrates is presented. The films display remarkable electronic properties such as high carrier mobility and high conductivity. When NiS thin film deposited on a flexible polyethylene terephthalate (PET) substrate is used as a fluorine doped tin oxide (FTO)-free counter electrode in dye-sensitized solar cells, it exhibits a solar-to-electric power conversion efficiency of 9.27 ± 0.26% with the highest conversion efficiency as high as 9.50% (vs 8.97 ± 0.07% exhibited by Pt-electrode). In addition, the NiS film deposited on a Ti-foil has demonstrated an outstanding catalytic activity for the hydrogen and oxygen evolution reactions from water.

PURPOSE: To assess the diagnostic accuracy of magnetic resonance imaging (MRI) perfusion against perfusion single photon emission tomography (SPECT) screening for chronic thromboembolic pulmonary hypertension (CTEPH). Ventilation/perfusion (V/Q) scintigraphy is recommended to screen for suspected CTEPH. It has previously been shown that 3D dynamic contrast-enhanced (DCE) lung perfusion MRI has a similar sensitivity for diagnosing CTEPH in comparison to planar perfusion scintigraphy; however, planar scintigraphy has now been largely replaced by SPECT, due to higher spatial resolution and sensitivity. MATERIALS AND METHODS: Consecutive patients with suspected CTEPH or unexplained pulmonary hypertension attending a referral center, who underwent lung DCE perfusion MRI at 1.5T, perfusion SPECT, and computed tomography pulmonary angiography (CTPA) within 14 days of right heart catheterization, from April 2013 to April 2014, were included. DCE-MR, SPECT, and CTPA were independently analyzed by two blinded radiologists. Disagreements were corrected by consensus. The gold standard reference for the diagnosis of chronic thromboemboli was based on a review of multimodality imaging and clinical findings. RESULTS: In all, 74 patients with suspected CTEPH underwent all three modalities. Forty-six were diagnosed with CTEPH (36) or chronic thromboembolic disease (CTED) (10). 3D DCE perfusion MRI correctly identified all patients (sensitivity of 100%), compared with a 97% sensitivity for SPECT. CONCLUSION: DCE lung perfusion MRI has increased sensitivity when compared with perfusion scintigraphy in screening for CTEPH. As MRI does not use ionizing radiation, it should be considered as a first-line imaging modality in suspected CTEPH. LEVEL OF EVIDENCE: 3

One-step and template-free synthesis of polyaniline nanobuds (PANI NBs), synthesized using anodic electrochemical polymerization method, is reported at room temperature onto a conducting indium-tin-oxide glass substrate. The PANI NBs are characterized for their structural, morphological, and electrochromic properties. Scanning electron microscopy image reveals NBs type architecture, perpendicular to the substrate surface. These NBs are broader at their bottoms and narrower at the tops. Individual NB has confirmed 30 nm top diameter and 100-200 nm length. Electrochemical supercapacitive behavior of the PANI NBs electrode is investigated by measuring cyclic voltammetry curves. Moderate specific capacitance of 128 F/g is achieved in the potential range of 0.2 to 1.0 V at 10 mV/s sweep rate in 0.5 M H2SO4 electrolyte. Influence of inner and outer charges on a resultant specific capaci- tance is also investigated. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 000: 000-000, 2012

Due to considerable impact on day-to-day life through the superior functions in energy, medicine, electronics, sensors and space industries, young researchers are being attracted towards the fields of nanotechnology and biotechnology. Selenium (Se) acts as an essential element in most organisms and is a beneficial nutrient in higher plants. Se nanostructures (NSs), i.e. nanospheres or nanoparticles (NPs) and nanowires (NWs), have unusual properties compared to their bulk counterparts. They have seven-fold lower toxicity than their other biologically utilizable materials. Several physical & chemical methods have been applied for the synthesis of Se NSs, but the development of eco-friendly routes is of considerable importance towards biological applications. Recently, microorganisms have been reported for the synthesis of Se NSs via the reduction of oxyions in anaerobic and aerobic environments. This review briefly proposes the recent developments in the microbial synthesis, characterization, and synthesis mechanism of Se NSs, along with their non-biological (solar, sensor, photocatalysis, etc.) and biological (anticancer, antioxidant, antiprotozoal, etc.) applications. Advantages of the Se NSs synthesized using green approaches, over the commonly used, are explored.

Metal chalcogenide thin films preparation by chemical methods are currently attracting considerable attention as it is relatively inexpensive, simple and convenient for large area deposition. A variety of substrates such as insulators, semiconductors or metals can be used since these are low temperature processes which avoid oxidation and corrosion of substrate. These are slow processes which facilitates better orientation of crystallites with improved grain structure. Depending upon deposition conditions, film growth can take place by ion-by-ion condensation of the materials on the substrates or by adsorption of colloidal particles from the solution on the substrate. Using these methods, thin films of group II–VI, V–VI, III–VI etc. have been deposited. Solar selective coatings, solar control, photoconductors, solid state and photoelectrochemical solar cells, optical imaging, hologram recording, optical mass memories etc. are some of the applications of metal chalcogenide films. In the present review article, we have described in detail, chemical bath deposition method of metal chalcogenide thin films, it is capable of yielding good quality thin films. Their preparative parameters, structural, optical, electrical properties etc. are described. Theoretical background necessary for the chemical deposition of thin films is also discussed.

Chemical bath deposition (CBD) is used for depositing different metal chalcogenide and oxide thin films through an ion-by-ion or by adsorption of colloidal particles from the solution on the substrate. In this review, we focused our intension on CBD zinc oxide (ZnO) films synthesis with different proposed deposition mechanisms and their integration into gas sensor and dye-sensitized solar cells. Due to the use of CBD ZnO films in gas sensors first time by our group, we presented film thickness, gas concentration and palladium sensitizer effect on the gas sensing properties in details. Review on CBD grown ZnO implication in dye-sensitized solar cells is also discussed in brief.