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The effects of air exposure are investigated for molybdenum trioxide (MoO3) covered with organic thin films using ultraviolet photoemission spectroscopy. It is found that the severe drop of the work function of MoO3 by air exposure is substantially reduced by the organic thin films. Both CuPc and C60 are used for the investigations. The results indicate that the MoO3 surface can be passivated by approximately two monolayers of organic thin films against exposure to air. [ABSTRACT FROM AUTHOR]

Abstract: The electronic structure evolution of interfaces of fullerene (C60) with copper phthalocyanine (CuPc) on highly oriented pyrolitic graphite (HOPG) and on native silicon oxide has been investigated with ultra-violet photoemission spectroscopy and inverse photoemission spectroscopy. The lowest unoccupied molecular orbital edge of C60 was found to be pinned at the interface with CuPc on SiO2. A substantial difference in the electron affinity of CuPc on the two substrates was observed as the orientation of CuPc is lying flat on HOPG and standing up on SiO2. The ionization potential and electron affinity of C60 were not affected by the orientation of CuPc due to the spherical symmetry of C60 molecules. We observed band bending in C60 on the standing-up orientation of CuPc molecules, while the energy levels of C60 on the flat lying orientation of CuPc molecules were observed to be flat. [Copyright &y& Elsevier]

Abstract: Back contact improvement is one of the most crucial issues for the formation of a low resistance contact and enhanced efficiency in CdS/CdTe based photovoltaic cells. We studied Ni/CdTe back contact formation with x-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS), and observed the effect of a thin MoO x inter-layer between Ni and CdTe films. Contrasting differences in the interface formation and core level structure were observed, indicating that the presence of a thin MoO x inter-layer was effective in reducing the reaction between Ni and the native tellurium oxide at the CdTe surface. The improvement of device performance is explained based on the evolution of core levels and the valence band region during the Ni/MoO x /CdTe interface formation, wherein MoO x serves as a high work function buffer layer. [Copyright &y& Elsevier]

Abstract: Indium tin oxide (ITO) is extensively used as a transparent electrode in photovoltaic cells and organic light emitting diodes. High surface work function (WF) of ITO is a crucial parameter for enhanced device performance. The ITO WF is usually around 4.3eV without any surface treatment. With surface treatments ITO WF, as high as 5.4eV has been reported. We designed a surface treatment method with which we achieved substantially high ITO surface work function of over 6.1eV. We observed changes in valence electronic structure and core levels, apart from surface cleaning. We also investigated interface formation of copper phthalocyanine (CuPc) on the high WF ITO. In the proximity of the interface the highest occupied energy level of CuPc was observed to be almost pinned to the Fermi level. We fabricated three simple devices with no to high treatment. The device results were observed to be consistent with the findings of electronic energy level alignment. [Copyright &y& Elsevier]

Mycobacterium Tuberculosis can survive in the air, with its ability depending on environmental factors such as Ultraviolet (UV) light. UV light can be generated from sunlight or UV-C lamps, which are utilized for air germ sterilization. This study aimed to assess the efficacy of room sterilization using a UV lamp in reducing airborne germ counts. This experimental research took place from March to September 2023 and employed a one-group pretest-posttest design. The research was carried out in 21 houses of tuberculosis patients in Kupang City. The intervention involved the use of 16-watt and 20-watt UV lamps in two rooms of each house. The variable measured was the airborne germ count, assessed by examining the Most Probable Number (MPN) coliforms, both before and after sterilization (UV light irradiation), calculated through laboratory examination. The collected germ count data were then statistically analyzed using the paired t-test. Room sterilization using a 16W UV lamp effectively reduced the number of room germs (p 0.046<0.05). Similarly, room sterilization with a 20W lamp significantly reduced the number of room germs in the households of tuberculosis patients (p 0.004<0.005). Ultraviolet lamps can be employed for sterilizing rooms in the homes of tuberculosis patients, particularly in cases where sunlight cannot penetrate the house. These lamps can eliminate airborne germs, thereby reducing their count and the risk of disease transmission within the household. [ABSTRACT FROM AUTHOR]

We report substantial work function (WF) recovery of air exposed molybdenum oxide thin films with vacuum annealing. We observed a sharp reduction in the MoOx WF (from 6.8 eV to 5.6 eV) as well as a very thin layer of oxygen rich adsorbate on the MoOx film after an hour of air exposure. The WF of the exposed MoOx film started to gradually recover with increasing annealing temperature in vacuum, and the saturation in the WF recovery was observed at 450 °C with WF ∼6.4 eV. We further studied the interface formation between the annealed MoOx and copper phthalocyanine (CuPc). The highest occupied molecular orbital (HOMO) level of CuPc was observed to be almost pinned to the Fermi level, strongly suggesting the possibility of efficient hole injection with the vacuum annealed MoOx film. [ABSTRACT FROM AUTHOR]

Present study was carried to determine the sand fly species composition, breeding sites ecology, seasonal abundance, and spatial distribution in district Malakand, Khyber Pakhtunkhwa, Pakistan. In addition, risk factors associated with cutaneous leishmaniasis (CL) were also evaluated. Survey of indoor and outdoor habitats was carried out using sticky traps in 31 villages of Dargai and Batkhela tehsils of Malakand. Soil from habitats of adult and immature sand flies was analysed. Questionnaire‐based household survey was also performed in these villages to assess risk factors associated with CL. Soil samples from selected CL positive households were analysed for its contents. Additionally, clinicoepidemiological data from local health centres was examined for the year 2019. Total of 3,140 sand flies belonging to 18 species were collected. Phlebotomus sergenti was the most abundant species (38.16%). Its abundance had a strong positive correlation with mean monthly relative humidity and negative correlation with average temperature. Phlebotomus sergenti and Phlebotomus papatasi were abundant at an elevation ranging from 320 to 1,120 m above sea level and in agricultural lands near human settlements. Flight height preference apparatus collected maximum sand flies at 30 cm (1ft) above the ground and all species associated negatively with height. Soil analysis from habitats of adult and immature flies showed that highest mean number of adults and immatures were recorded from silt loam which carried highest concentrations of K2O, Mg, Ca, and Zn. Number of immature sand flies correlated moderately (r =.7, p <.05) with K2O soil concentrations. There was significant similarity between organic matter contents in soil samples from positive breeding sites and CL households (Wilcoxon rank‐sum test, p =.1976). In multivariate analysis model for CL risk factors, age (26–35 and >35 years), knowledge of leishmaniasis, living in a middle and upper class, preachers visit to villages, and assumption that Afghan refugees are more prone to CL were significant. CL patient's archived data from health centres showed that majority of patients had lesions on face and hands. Patient's influx was highest in February and March. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented discussing the roles of pharmacists in clinical pharmacy as active healthcare professionals.

Interfacial electronic structures of MoO 3 and LiF-modified pentacene (PEN)/fullerene (C 60 )-based charge generation layer (CGL) have been investigated with photoemission spectroscopy. Important characteristics controlling its functional effectiveness have been analyzed for charge transport properties in tandem organic lighting-emitting diodes (TOLEDs). It is found that a small energy offset at the PEN/C 60 heterojunction makes it easy to transfer electrons from PEN to C 60 even under a small applied bias, facilitating the occurrence of charge generation. The band bending observed in both PEN and C 60 is beneficial to exciton-dissociation and charge transport in opposite directions. At the MoO 3 /PEN interface, the high work function (WF) of MoO 3 brings the highest occupied molecular orbital (HOMO) onset up to the Fermi level ( E F ) not only for PEN but also for most hole transport layer (HTL) materials of the adjacent electroluminescent (EL) unit as this CGL is connected into TOLED. Therefore, holes can be efficiently injected from PEN into this EL unit. Similarly, at the C 60 /LiF interface, the low WF of the LiF buffer layer makes the lowest unoccupied molecular orbital (LUMO) to pin close to the E F not only for C 60 but also for most electron transport layer (ETL) materials of the other EL unit, which induces the electrons to inject easily from C 60 into that EL unit by tunneling through the thin LiF film. The favorable energy level alignment can effectively enhance charge generation, transport, and injection. The advantage of the MoO 3 /PEN/C 60 /LiF structure is that thus formed CGL can greatly reduce the voltage drop and thus enhance the power efficiency (PE) of the corresponding TOLED. [ABSTRACT FROM AUTHOR]

A buffer layer based on a Te/Cu bi-layer useful for forming ohmic contact to p -CdTe has been developed for application in CdS/CdTe solar cells. The bi-layer buffer was prepared by vapor deposition and a thermal annealing (~200 °C) was required for activation. Enhanced efficiency and stability were obtained by optimizing the Cu/Te compositions and the thermal activation conditions. Characterization by XRD, XPS, and PL indicates that under the thermal activation conditions Cu diffuses rapidly in the Te without forming Cu x Te compounds. The enhanced stability can be attributed to the mediation of Cu diffusion into CdTe by the Te layer. The Te/Cu buffers are particularly useful for the fabrication of ultra-thin CdS/CdTe solar cells. [ABSTRACT FROM AUTHOR]

MoOxhas been used for organicsemiconductordoping, but it had been considered an inefficient and/or unstabledopant. We report that MoOxcan stronglyand stably dope carbon nanotubes and graphene. Thermally annealedMoOx-CNT composites can form durable thinfilm electrodes with sheet resistances of 100 Ω/sq at 85% transmittanceplain and 85 Ω/sq at 83% transmittance with a PEDOT:PSS adlayer.Sheet resistances change less than 10% over 20 days in ambient andless than 2% with overnight heating to 300 °C in air. The MoOxcan be easily deposited either by thermalevaporation or from solution-based precursors. Excellent stabilitycoupled with high conductivity makes MoOx-CNT composites extremely attractive candidates for practical transparentelectrodes. [ABSTRACT FROM AUTHOR]