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The thermoelectric (TE) performance of conducting polymers can be improved by the incorporation of carbon nanomaterials. In this work, the impact of carbon black (CB) on polypyrrole (PPy) and polypyrrole/polyaniline (PPy/PANI) binary composite have been investigated. Herein, PPy/PANI binary composite was initially prepared through chemical oxidative polymerization and then solution mixed with CB to form PPy/PANI/CB ternary nanocomposite. The structural and morphological analyses confirmed the formation of composites, and the strong interaction present between polymer matrix and CB. This was further confirmed by theoretical study, which showed strong noncovalent interaction and high complex stability between the materials. The thermoelectric results showed that both the electrical conductivity (σ) and Seebeck coefficient (S) has been increased with the increase in CB content (from 10 wt% to 30 wt%) and temperature (303 K to 373 K), while the thermal conductivity (κ) increase was low. The ternary nanocomposite involving 30 wt% of CB was found to be the most promising material which showed an enhanced power factor (PF) of 0.0251 μW/mK

A substantial reduction in the thermal conductivity for strontium titanate (ABO3) perovskite structure was realized for the A-site substitution of gadolinium (rare earth element) in the SrTiO3 ceramics.

Schematic illustrations of DSSC device.

In this work, we investigated the effect of La-site cation deficiency and Sr-substitution on the thermoelectric properties of polycrystalline samples of the La0.9−xSrxCoO3 (x = 0, 0.03, 0.05) ceramic synthesized via a solid-state reaction.

We report a facile and low-cost deposition of Tin sulfide (SnS) nanosheets and its performance for Near Infra-red (NIR) Photodetection under the UV to NIR illumination. Orthorhombic phase of SnS has been observed in the phase identification analysis. The optical absorption edge was observed at 1030 nm, and the band gap was found to be 1.2 eV. Nanosheets morphology along with flakes identified from the scanning electron micrograph analysis. Photoresponse measurement was studied under dark and illumination with a constant bias voltage of 1.5 V and the enhanced photocurrent is observed. The higher spectral responsivity of 0.19 A/W at 1030 nm has been observed in spectral response curve recorded from 300 nm to 1100 nm. The cyclic photoresponse of the SnS photodetectors shows good cyclability with illumination turn on and off alternatively with the time interval of 20 s. The response time (Tr) and recovery time (Tτ) were found to be 2 s and 4 s, respectively. The detectivity Dt of the SnS nanosheets photodetector to be 9.213×1011 Jones. The wavelength-dependent photodetection shows the maximum response at 1030 nm and the higher photosensitivity. Finally, the external quantum efficiency of the fabricated NIR photodetector was found to be 27%.

Lanthanum Cobaltate (LaCoO3) ceramic has high seebeck coefficient (S) at room temperature which makes it a promising material for thermoelectric application, but suffer from low figure of merit (ZT) due to its large thermal conductivity (κ). Herein, a strategy of isovalent substitution in Co site was effectively attempted to induce phonon scattering in order to decrease κ. In this study, the perovskites were prepared by solid state reaction using corresponding metal oxide precursors at 1373 K. XRD analysis of the prepared perovskites revealed excellent phase purity and the homogeneity of the prepared samples were confirmed by HR-SEM mapping. The low κ value of 1.38 W/mK was achieved at 753 K for Al- substituted LaCoO3. The significant decrease of thermal conductivity was due to the lattice disorder and effect of mass upon Al substitution. The strategy of isovalent substitution to achieve low thermal conductivity potentially opens up a new way for enhancing the thermoelectric performance.

Figure (a) Power factor (S2σ), (b) zT of sintered Ag2Se (S1), Ag1.99Se (S2), Ag1.96Se, and Ag1.93Se (S4) samples.

In this work, reduced graphene oxide-wrapped α-Mn2O3/α-MnO2 nanowires were prepared by heat treating (450 °C) of hydrothermally produced sample. XRD patterns confirmed the formation of α-Mn2O3 and α-MnO2 mixed phase. FE-SEM revealed the formation of nanowires with the average diameter, 38 nm. The rGO wrapping on the nanowires was confirmed by TEM. The presence of Mn3+ and Mn4+ species in the catalyst was confirmed in Raman and XPS analysis. The rGO-wrapped nanowires with high surface area (45.30 m2 g−1) show better electrocatalytic reduction performance in alkaline medium. The rGO-wrapped α-Mn2O3/α-MnO2 catalyst exhibits a positive onset potential, + 0.79 V and nearly 4-electron transfer pathway for ORR.

Numerous inorganic and organic counter electrodes (CEs) have been fabricated for dye-sensitized solar cells (DSSCs) instead of platinum (Pt) CE. However, MoS2 and carbon nanocomposite have played an important role in CEs due to their superior electrochemical properties and high chemical stability. N-doped graphene quantum dot (N-GQD) @ MoS2 @ reduced graphene oxide (rGO) nanocomposite was synthesized by the two-step hydrothermal method. The morphology of as-synthesized nanocomposites was studied using field emission scanning electron microscope (FE-SEM) and scanning transmission electron microscopy (STEM). It confirms the formation of sphere-like MoS2 composed of nanosheets on the surface of rGO sheets. The N-GQD@MoS2@rGO composites confirmed the presence of MoS2, rGO, and N-GQD by X-ray diffraction (XRD) and Raman spectra. The chemical composition and purity of N-GQD@MoS2@rGO was examined by the X-ray photoelectron spectroscopy analysis technique. The electrochemical property of the as-fabricated CEs was studied by cyclic voltammetry (CV) analysis by using the iodine-based electrolyte. The N-GQD@MoS2@rGO shows the superior catalytic property due to more electrochemical active site and electrical conductivity property of rGO and MoS2. The DSSCs device assembled with as-fabricated CEs and their photovoltaic power conversion efficiency (η) of MoS2 was 2.01%, MoS2@rGO was 3.92%, N-GQD@MoS2 was 3.53%, N-GQD@MoS2@rGO was 4.65%, and Pt was 5.17%.

A substantial reduction in the thermal conductivity for strontium titanate (ABO

Emulgels (emulsion gels) are a class of biphasic semi-solid formulations, having aqueous and non-aqueous phases, delivering both hydrophilic and lipophilic agents. The main advantage of an emulgel is that lipophilic drugs can be easily formulated as emulgels. Rutin trihydrate is an herbal drug used for topical treatment of inflammation. However, its poor water solubility (0.125 mg/ml) presents a hindrance for its local bioavailability and limits effective anti-inflammatory activity. The aim of the current study was to formulate and optimize rutin trihydrate emulgel to enhance its efficacy and stability. 28 formulations were developed with various types of gelling agents like Carbapol 934 (0.8 and 1% w/v), Xanthum gum (1.5 and 2% w/v), HPMCk15 (2, 2.5 and 3% w/v),HPMC K100 (2, 2.5% w/v), guar gum (1, 1.5 and 2% w/v), badam gum (1% w/v) and using various permeation enhancers like clove oil, eucalyptus oil and oil of orange (10 and12.5% v/v). The optimised formulation (f8) was yellow in colour, homogeneous with good consistency, possessed pH of 6.51±0.04 that is very close to that of normal skin (6-7), drug content of 98.7%, viscosity of 14,680cps at 30rpm, spreadability 13.5gm.cm/sec and extrudability 36.2% and in vitro drug release of 79.3% for 7 hrs, ex vivo drug release of 70.08% was stable for 3 months and was having comparable anti inflammatory activity with that of marketed formulation.

AgSbSe2 is one of the important Te-free chalcogenides in I–V–VI2 semiconductors, showing attractive functional properties and enhancing the thermoelectric performance. Here we report the thermoelectric performance of the polycrystalline p-type AgSbSe2 nanostructured compound synthesized via a hydrothermal method followed by cold-press technique. In the as-prepared sample, the synergistic combination of low thermal conductivity (0.589 W m K−1) and high-power factor (3.3 μW cm K−2) has been observed to successfully boost the thermoelectric figure of merit. The cubic phase structure and disordered lattice of AgSbSe2 were confirmed by XRD and HRTEM analyses. The valence states of Ag+, Sb3+ and Se2− were confirmed from XPS. The presence of atomic-scale disorder results from Sb–Se bond anharmonicity because of the electrostatic repulsion between the charge of Se and the lone pair of Sb, as well as nanoscale grains coupled with strong Sb–Se bond anharmonicity. This allows for an effective phonon scattering, resulting in reduced thermal conductivity. The AgSbSe2 system offers promising thermoelectric properties to restore traditional metal tellurides for intermediate power generation. The possible transport mechanism along with lattice anharmonicity created by lone-pair electrons is proposed.

In the past few decades, air and water pollution by organic dyes has become a serious concern due to their high toxicity. Removal of these organic dyes from polluted water bodies is a serious environmental concern and the development of new advanced photocatalytic materials for decomposing organic dyes can be a good solution. In this work, layered molybdenum disulfide/nickel disulfide (MoS2/NiS2) nanocomposites with various NiS2 content was synthesized by a one-step hydrothermal method using citric acid as a reducing agent. The X-ray diffraction pattern shows the hexagonal and cubical crystal structure of MoS2 and NiS2, respectively. Morphological analysis confirms the formation of MoS2/NiS2 nanosheets. The elemental composition of the samples was carried out by XPS, which shows a significant interaction between NiS2 and MoS2. The photocatalytic performance of MoS2/NiS2 nanocomposites was studied by the degradation of rhodamine B (RhB). Ni-4 sample shows higher photocatalytic activity with a maximum degradation of 90.61% under visible light irradiation for 32 min.

Hierarchical nanostructures and the effects of ligands on their structure formation were investigated. Morphological analysis showed the change in the morphology from nanospindles to hollow hexagonal nanodisks with the change in ligands. Structural analysis exhibited the formation of both hexagonal ZnO and monoclinic CuO structures in the composition. The elemental composition confirms the presence of CuO and ZnO in the composition. An ultra-fast degradation was achieved for the nanocomposites. The ZnO/CuO composite with ethylenediamine showed the best activity by degrading 98.77% of the methylene blue dye in 36 min. A possible photocatalytic mechanism is proposed.

Microbial decolourization of textile dyes is cost effective and eco-friendly method. Two bacterial species (Bacillus cereus and Bacillus flexus) and one fungal species Aspergillus niger were isolated from the dye spilled soil and identified through biochemical and molecular characterization by gene sequencing. Phylogenetic tree was constructed with blast result of closely related sequences using Mega X software with 500 bootstrap. The phylogenetic tree of isolated species showed great diversity with Bacillus and Aspergillus species. A. niger showed 98% of dye degradation capacity, B. cereus has very poor ability to degrade dye when compared with B. flexus. The sequences of B. cereus (MH299975), B. Flexus (MH299976) and A. niger (MH299977) were submitted to NCBI gene bank for global retrieval.

Herein, we report the synthesis of quaternary chalcopyrite sulfide semiconductors Cu2MSnS4 (M = Zn, Ni, Co, Mn, Fe) by a hydrothermal process. The formation of kesterite structure was confirmed by XRD. XPS analysis confirmed the composition of Cu–(Zn, Ni, Co, Mn, Fe)–Sn–S. Morphologies of the hierarchical structures were characterized. Hall measurements revealed that the Zn was replaced with Ni which exhibited higher carrier density and lower resistivity. Cyclic voltammetry measurements showed peak-to-peak separation (Epp) value of Cu2NiSnS4 about 268 mV, which was smaller than that of Cu2ZnSnS4, and a higher cathodic current density (Ic) of 0.000334 mA cm−2 compared to those of Pt. This indicated that the electrocatalytic activity of Cu2NiSnS4 was better for the I−/I3− redox reaction, with a long-term stability for 250 cycles.

CdTe and 1–5 wt% molybdenum-doped CdTe materials were prepared by ball milling method. Then the ball-milled samples were deposited on a glass substrate at room temperature by an electron beam evaporation method. The structural, optical, morphological, electrical, and photo-response properties of CdTe and Mo-doped CdTe (CdTe:Mo) samples were investigated. The prepared samples exhibit a cubic structure of CdTe. X-ray diffraction pattern (XRD) showed that the deposited films belong to the cubic structure with a preferential growth along (111) plane. The peak shift in the lower side of 2θ was observed due to incorporation of Mo into the CdTe matrix. Surface morphology of the prepared CdTe and CdTe:Mo ball-milled samples showed the formation of various agglomerated structures. Scanning electron microscope images depicted the formation of high dense agglomerated grains on the film surface with varying sizes as a function of Mo concentration. The optical bandgap was increased from 1.38 to 1.54 eV with raising the Mo concentration in CdTe films. Enhanced optical absorption coefficients (~ 17 × 104 cm−1) were observed for 3 and 4 wt% Mo doped CdTe thin films. Hall measurement studies revealed that Mo doped CdTe (3 wt%) film possesses a low resistivity of 34 × 103 Ω cm. The CdTe and CdTe:Mo films exhibit p-type conduction. The high photo-response of 0.088 AW−1 is observed for 3 wt% Mo-doped CdTe thin film.

Context: Infections with methicillin-resistant Staphylococcus aureus (MRSA) greatly influence clinical outcome. Molecular characterisation of MRSA can help to predict their spread and to institute treatment and hospital protocols. Aim: The aim of this study is to understand the diversity of MRSA in a tertiary care hospital in Hyderabad, India. Settings and Design: Samples collected at Gandhi Medical College, Hyderabad, and designed to assess hospital-or community-associated MRSA (HA-MRSA or CA-MRSA). Subjects and Methods: MRSA were subjected to antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE), spa typing, multi-locus sequence typing and staphylococcal cassette chromosome–mec (SCCmec) typing. Statistical Analysis Used: Discriminatory index and 95% confidence interval. Results: Of the 30 MRSA, (a) 18 and 12 were HA-MRSA and CA-MRSA, respectively, and (b) 23.3% and 6.6% displayed induced clindamycin and intermediate vancomycin resistance, respectively. Genetic diversity was evident from the presence of (a) 20 pulsotypes, (b) eight spa types, with the predominance of t064 (n = 9) and (c) seven sequence types (ST), with the preponderance of ST22 and ST8 (9 each). ST22 and ST8 were the most prevalent among HA-MRSA and CA-MRSA, respectively. SCCmec type IV was the most frequent (n = 8). 44.4% of HA-MRSA belonged to SCCmec IV and V, whereas 33.3% of CA-MRSA belonged to SCCmec I and III; 33.3% (5/15) of the isolates harbouring the pvl gene belonged to SCCmec IVC/H. Conclusions: ST8 was a dominant type along with other previously reported types ST22, ST239, and ST772 from India. The observations highlight the prevalence of genetically diverse clonal populations of MRSA, suggesting potential multiple origins.

Hierarchical MoO

Solid solution SnSe0.75S0.25 has potential to improve thermoelectric performance via ultra-low thermal conductivity as compared to the pristine SnSe which originates from phonon scattering due to disordered atoms of selenium (Se) and sulfur (S). SnSe0.75S0.25 and Cu-doped SnSe0.75S0.25 compounds were prepared via high energy ball milling and pelletized by a spark plasma sintering (SPS) process. Dislocation and point defects were successfully introduced by SnSe0.75S0.25. The existence of S in the Se site induced mass fluctuation which favors high-frequency phonon scattering. This leads to an impressively ultra-low thermal conductivity (κT) value of 0.258 W mK−1 at 753 K for SnSe0.75S0.25. Next, the Cu dopant was selected to enhance the electrical conductivity, which improved from 514.44 S m−1 (SnSe0.75S0.25) to 725.08 S m−1 for Sn0.98Cu0.02Se0.75S0.25 at 738 K. Interestingly, the Cu dopant induced nanoprecipitates of Cu2Se inside the grains, which further strengthens the phonon scattering. The Cu2Se nanoprecipitates and various defects at the grain boundaries contributed to a lower κT of 0.295 W mK−1 at 753 K for a Sn0.94Cu0.06Se0.75S0.25 sample. Moreover, the maximum figure of merit of (ZT) ∼0.19 at 738 K was attained for the Sn0.98Cu0.02Se0.75S0.25 sample.