Chemically synthesized Bi2S3, CuS and Bi2S3/CuS heterostructure materials as counter electrode: Dye sensitized solar cell application

143-149In the present work, we have successfully synthesized Bi2S3, CuS, and its heterojunction Bi2S3/CuS thin film on fluorine doped tin oxide (FTO) coated glass as counter electrodes. These depositions are done by simple, cost effective, and simply executable sequential chemical bath deposition (S-CBD) method. Well optimized preparative parameters led to the formation of good quality thin films of Bi2S3 and CuS films and heterojunction. The structural validation Bi2S3, CuS, and its heterojunction were achieved by X-ray diffraction and Raman scattering, surface morphological study observed through Scanning Electron Microscopy (SEM) and topology was confirmed by Atomic Force Microscopy (AFM). We have employed Bi2S3/CuS heterostructure as a counter electrode (CE) in dye-sensitized solar cell (DSSC). We have observed different parameters like short circuit current density (Jsc), open circuit voltage (Voc), Fill Factor (FF) and efficiency (n) by Current–voltage (J-V) characteristics. Though we do not achieve an anticipated outcome for heterostructure compared with conventional Platinum and Carbon black counter electrode, CuS separately found worthy as Counter electrode (CE) in DSSC

Chemically synthesized Bi2S3, CuS and Bi2S3/CuS heterostructure materials as counter electrode: Dye sensitized solar cell application

In the present work, we have successfully synthesized Bi2S3, CuS, and its heterojunction Bi2S3/CuS thin film on fluorine doped tin oxide (FTO) coated glass as counter electrodes. These depositions are done by simple, cost effective, and simply executable sequential chemical bath deposition (S-CBD) method. Well optimized preparative parameters led to the formation of good quality thin films of Bi2S3 and CuS films and heterojunction. The structural validation Bi2S3, CuS, and its heterojunction were achieved by X-ray diffraction and Raman scattering, surface morphological study observed through Scanning Electron Microscopy (SEM) and topology was confirmed by Atomic Force Microscopy (AFM). We have employed Bi2S3/CuS heterostructure as a counter electrode (CE) in dye-sensitized solar cell (DSSC). We have observed different parameters like short circuit current density (Jsc), open circuit voltage (Voc), Fill Factor (FF) and efficiency (n) by Current–voltage (J-V) characteristics. Though we do not achieve an anticipated outcome for heterostructure compared with conventional Platinum and Carbon black counter electrode, CuS separately found worthy as Counter electrode (CE) in DSSC

ZnO/CuSCN nano-heterostructure as a highly efficient field emitter: a combined experimental and theoretical investigation

We report the synthesis of two-dimensional porous ZnO nanosheets, CuSCN nanocoins, and ZnO/CuSCN nano-heterostructure thin films grown on fluorine-doped tin oxide substrates via two simple and low-cost solution chemical routes, i.e., chemical bath deposition and successive ionic layer adsorption and reaction methods. Detail characterizations regarding the structural, optoelectronic, and morphological properties have been carried out, which reveal high-quality and crystalline synthesized materials. Field emission (FE) investigations performed at room temperature with a base pressure of 1 × 10–8 mbar demonstrate superior FE performance of the ZnO/CuSCN nano-heterostructure compared to the isolated porous ZnO nanosheets and CuSCN nanocoins. For instance, the turn-on field required to draw a current density of 10 μA/cm2 is found to be 2.2, 1.1, and 0.7 V/μm for the ZnO, CuSCN, and ZnO/CuSCN nano-heterostructure, respectively. The observed significant improvement in the FE characteristics (ultralow turn-on field of 0.7 V/μm for an emission current density of 10 μA/cm2 and the achieved high current density of 2.2 mA/cm2 at a relatively low applied electric field of 1.8 V/μm) for the ZnO/CuSCN nano-heterostructure is superior to the isolated porous ZnO nanosheets, CuSCN nanocoins, and other reported semiconducting nano-heterostructures. Complementary first-principles density functional theory calculations predict a lower work function for the ZnO/CuSCN nano-heterostructure (4.58 eV), compared to the isolated ZnO (5.24 eV) and CuSCN (4.91 eV), validating the superior FE characteristics of the ZnO/CuSCN nano-heterostructure. The ZnO/CuSCN nanocomposite could provide a promising class of FE cathodes, flat panel displays, microwave tubes, and electron sources

A Look Behind the Scenes at COVID-19: National Strategies of Infection Control and Their Impact on Mortality

(1) Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began spreading across the globe in December and, as of 9 July 2020, had inflicted more than 550,000 deaths. Public health measures implemented to control the outbreak caused socio-economic havoc in many countries. The pandemic highlighted the quality of health care systems, responses of policymakers in harmony with the population, and socio-economic resilience factors. We suggest that different national strategies had an impact on mortality and case count. (2) Methods: We collected fatality data for 17 countries until 2 June 2020 from public data and associated these with implemented containment measures. (3) Results: The outcomes present the effectiveness of control mechanisms in mitigating the virus for selected countries and the UAE as a special case. Pre-existing conditions defined the needed public health strategies and fatality numbers. Other pre-existing conditions, such as temperature, humidity, median age, and low serum 25-hydroxyvitamin D (25(OH)D) concentrations played minor roles and may have had no direct impact on fatality rates. (4) Conclusions: Prevention, fast containment, adequate public health strategies, and importance of indoor environments were determining factors in mitigating the pandemic. Development of public health strategies adapted to pre-existing conditions for each country and community compliance with implemented policies ensure the successful control of pandemics

Probing impact on magnetic behavior of cobalt layer grown on thick MoS 2_{2} 2 layer

Abstract Understanding the metal-semiconductor heterostructure interface is crucial for the development of spintronic devices. One of the prospective candidates and extensively studied semiconductors is molybdenum disulfide (MoS $$_{2}$$ 2 ). Herein, utilizing Kerr microscopy, we investigated the impact of thick MoS $$_{2}$$ 2 on the magnetic properties of the 10 nm Co layer. A comparative study on $$\hbox {Co}/\hbox {MoS}_{2}$$ Co / MoS 2 and Co/Si shows that coercivity increased by 77% and the Kerr signal decreased by 26% compared to Co grown on Si substrate. In addition, the Co domain structure significantly changed when grown on MoS $$_{2}$$ 2 . The plausible reason for the observed magnetic behavior can be that the Co interacts differently at the interface of MoS $$_{2}$$ 2 as compared to Si. Therefore, our studies investigate the interfacial effect on the magnetic properties of Co grown on thick MoS $$_{2}$$ 2 layer. Furthermore, our results will help in developing next-generation spintronic devices

Nanocrystalline CdTe thin films by electrochemical synthesis

Cadmium telluride thin films were deposited onto different substrates as copper, Fluorine-doped tin oxide (FTO), Indium tin oxide (ITO), Aluminum and zinc at room temperature via electrochemical route. The morphology of the film shows the nanostructures on the deposited surface of the films and their growth in vertical direction. Different nanostructures developed on different substrates. The X-ray diffraction study reveals that the deposited films are nanocrystalline in nature. UV-Visible absorption spectrum shows the wide range of absorption in the visible region. Energy-dispersive spectroscopy confirms the formation of cadmium telluride