Search Results (30)

ZnO/SiC nanocomposite materials possess significant potential for various technological fields due to their extraordinary optical, electrical, thermal, and mechanical properties. The synthesis methods, material properties, and diverse applications of ZnO/SiC composites have been systematically explored in this study. The potential application areas of this nanocomposite include their roles in photocatalysis, optoelectronic devices, gas sensors, and photovoltaic systems. The synergetic effects of ZnO and SiC are analyzed to highlight their advantages over their individual components. Future research directions must focus on the remaining challenges to optimize these nanoscale composite materials for industrial and emerging applications. Full article

Ensuring adherence to antimalarial treatment is crucial for achieving a radical cure and elimination of malaria, especially in hard-to-reach areas. We conducted this study to assess the current scenario of drug adherence in four endemic sub-districts of Bangladesh. Among 110 enrolled participants, 70% were mono-infected with Plasmodium falciparum and the remaining 30% with P. vivax. The overall treatment adherence frequency was 92.7% (95% CI: 83.0–96.3%). A total of eight participants were found to be nonadherent to treatment and all of them were from Bandarban. Level of nonadherence was equally observed in two age groups: 11–17 and 18+ years. However, male participants (n = 6) were found to be more nonadherent than females (n = 2). Among 7.3% with nonadherence to treatment, a single participant with P. falciparum mono-infection refused to take medication and became nonadherent. Remaining participants stated that they were feeling well and going to work, thus leaving treatment course uncompleted. Although overall compliance with malaria medication seems good, a gradual increase in noncompliance to P. vivax malaria treatment suggests that the National Malaria Elimination Program must be enhanced and monitored to fulfil the projected malaria elimination goal before 2030 from Bangladesh. Full article

In the last several decades, metal oxide thin films have attracted significant attention for the development of various existing and emerging technological applications, including pH sensors. The mandate for consistent and precise pH sensing techniques has been increasing across various fields, including environmental monitoring, biotechnology, food and agricultural industries, and medical diagnostics. Metal oxide thin films grown using physical vapor deposition (PVD) with precise control over film thickness, composition, and morphology are beneficial for pH sensing applications such as enhancing pH sensitivity and stability, quicker response, repeatability, and compatibility with miniaturization. Various PVD techniques, including sputtering, evaporation, and ion beam deposition, used to fabricate thin films for tailoring materials’ properties for the advanced design and development of high-performing pH sensors, have been explored worldwide by many research groups. In addition, various thin film materials have also been investigated, including metal oxides, nitrides, and nanostructured films, to make very robust pH sensing electrodes with higher pH sensing performance. The development of novel materials and structures has enabled higher sensitivity, improved selectivity, and enhanced durability in harsh pH environments. The last decade has witnessed significant advancements in PVD thin films for pH sensing applications. The combination of precise film deposition techniques, novel materials, and surface functionalization strategies has led to improved pH sensing performance, making PVD thin films a promising choice for future pH sensing technologies. Full article

With the sharp increase in global energy demand, industrial and residential buildings are responsible for around 40% of the energy consumed with most of this energy portion being generated by non-renewable sources, which significantly contribute to global warming and environmental hazards. The net-zero energy building (NZEB) concept attempts to solve the global warming issue, whereby a building will produce, on-site, its required energy demand throughout the year from renewable energy sources. This can be achieved by integrating photovoltaic (PV) building materials, called building-integrated photovoltaic (BIPV) modules, throughout the building skin, which simultaneously act as construction materials and energy generators. Currently, architects and builders are inclined to design a building using BIPV modules due to the limited colors available, namely, black or blue, which result in a monotonous building appearance. Therefore, there is an increasing demand/need to develop modern, aesthetically pleasing BIPV green energy products for the use of architects and the construction industry. This review article presents the current stage and future goal of advanced building integrated photovoltaic systems, focusing on the aesthetically appealing BIPV systems, and their applications towards overcoming global challenges and stepping forward to achieve a sustainable green energy building environment. Additionally, we present the summary and outlook for the future development of aesthetically appealing building integrated photovoltaic systems. Full article

Bangladesh’s railway system mostly uses typical manual railway crossing techniques or boom gates through its 2955.53 km rail route all over the country. Accidents frequently happen at railway crossings due to the lack of quickly operating gate systems, and to fewer safety measures at the railway crossing as well. Currently, there are very few automatic railway crossing systems available (without obstacle detectors). Additionally, all of them are dependent on the national power grid, without a backup plan for any emergency cases. Bangladesh is still running a bit behind in generating enough power for its consumption; hence, it is not possible to have a continuous power supply at all times all over the countryside. We aim to design and develop a smart railway crossing system with an obstacle detector to prevent common types of accidents at railway crossing points. We use two infrared (IR) sensors to operate the railway crossing systems, which are controlled by an Arduino Uno. This newly designed level crossing system is run with the help of sustainable renewable energy, which is cost-effective and eco-friendly, and applied under the national green energy policy towards achieving sustainable development in Bangladesh as a part of the global sustainable goal to face climate change challenges. We have summarized the simulated the results of several renewable energy sources, including a hybrid system, and optimized the Levelized Cost of Energy (LCOE) and the payback periods. Full article

The electricity crisis is a common issue in Bangladesh; however, recently the electricity scenario has been getting worse due to various reasons including power generation and distribution all over the country. Meanwhile, the large number of people requires a huge amount of energy which is not possible to be met by the national grid due to the limited power generation from different plants. Among all renewable energy sources, the solar photovoltaics (PV) system is the best choice as a generation source, either off-grid or with a grid-tied connection, to reduce the pressure on the national grid. In Bangladesh, there are more than 175,000 schools, and it is possible to generate a huge amount of renewable (solar) power to supply all the schools by using rooftop PV systems. We propose a new approach that combines solar energy harvesting and savings to make the schools self-sufficient and energywise. We performed a Hybrid Optimization Model for Multiple Energy Resources (HOMER) pro simulation and find that it was possible to generate approximately 200 megawatts (MW) of power. We conducted a feasibility study on generating power from rooftop PV systems on school buildings and reduced the power consumption using retrofitted thin-film-coated glass by around 16–20% per day depending on the school size, which can help the national power grid system by either making all the schools off-grid or grid-connected to supply power to the national grid. In addition, we perform a HelioScope simulation to investigate the maximum upscaling of PV sizing for the rooftops of school buildings in Bangladesh to realize how to make each school a mini solar power station in the future. The HelioScope simulation performance showed that it was possible to generate approximately 96,993 kWh per year from one school building. Full article

Since 2007, at the Electron Science Research Institute (ESRI) nano-fabrication laboratories, Edith Cowan University, Australia, we have devoted research efforts to the synthesis and characterization of bismuth-containing ferrite-garnet-type thin-film magneto-optic (MO) materials of different compositions. We report on the growth and characteristics of radio frequency (RF) magnetron sputtered bismuth-substituted iron-garnet thin films. We study the process parameters associated with the RF magnetron sputter deposition technique and investigate the results of optimizing process parameters. To achieve the best MO properties, we employ a few unique techniques, such as co-sputtered nanocomposite films and all-garnet multilayer structures, as well as the application of oxygen plasma treatment to amorphous garnet layers immediately following the deposition process. We demonstrated a remarkable enhancement in the MO properties of Bi-containing ferrite-type garnet thin-film materials, including record-high MO figures of merit and improved conventional and unconventional hysteresis loops of Faraday rotation. Previously unpublished research results on the forward-looking applications of magnetic garnet coatings applied to microparticles of advanced luminescent materials are reported. In the context of developing the next-generation ultra-fast optoelectronic devices, such as light intensity switches and modulators, high-speed flat panel displays, and high-sensitivity sensors, it is important to consider the desirable optical, magnetic, and magneto-optic properties that are found in highly bismuth-substituted iron garnet thin-film materials of various composition types. Full article

The building integrated photovoltaic (BIPV) system is one of the contributors which has enormous potential to reach the goal of net-zero energy buildings (NZEB) that significantly reduce the use of fossil fuels that contribute to global warming. However, the limitations of the visual and aesthetic appearance of current BIPV systems make this aspiration unlikely. This study investigates the limitations of the single-color-based PV modules that are dull in appearance and have low photo-conversion efficiency (PCE). In order to solve this issue, we designed, developed, and characterized micro-patterned-based multicolored photovoltaic (MPCPV) modules which are applicable to net-zero building and development. Our newly developed MPCPV module exhibits an aesthetically attractive and flexible building color suitable for industrial application. Furthermore, the MPCPV module possesses an efficiency of 9.6%, which is 4.1% higher than a single-color PV module (5.5%) but closer to conventional thin-film PV modules. In addition, the other output parameters, such as short-circuit current (I_sc), open-circuit voltage (V_oc), maximum power (P_max), and fill factor (FF), indicate that our developed colored PV module is suitable for modern infrastructures that will enable energy generation on-site without compromising the aesthetic appearance. Finally, this research will have a substantial influence on the NZEB and will play an important part in the development of a sustainable environment. Full article

Dental caries, a global oral health concern, is a biofilm-mediated disease. Streptococcus mutans, the most prevalent oral microbiota, produces extracellular enzymes, including glycosyltransferases responsible for sucrose polymerization. In bacterial communities, the biofilm matrix confers resistance to host immune responses and antibiotics. Thus, in cases of chronic dental caries, inhibiting bacterial biofilm assembly should prevent demineralization of tooth enamel, thereby preventing tooth decay. A high throughput screening was performed in the present study to identify small molecule inhibitors of S. mutans glycosyltransferases. Multiple pharmacophore models were developed, validated with multiple datasets, and used for virtual screening against large chemical databases. Over 3000 drug-like hits were obtained that were analyzed to explore their binding mode. Finally, six compounds that showed good binding affinities were further analyzed for ADME (absorption, distribution, metabolism, and excretion) properties. The obtained in silico hits were evaluated for in vitro biofilm formation. The compounds displayed excellent antibiofilm activities with minimum inhibitory concentration (MIC) values of 15.26–250 µg/mL. Full article

The primary focus of this review article mainly emphasizes the light absorption enhancement for various nanostructured gratings assisted metal-semiconductor-metal photodetectors (MSM-PDs) that are so far proposed and developed for the improvement of light capturing performance. The MSM-PDs are considered as one of the key elements in the optical and high-speed communication systems for applications such as faster optical fiber communication systems, sensor networks, high-speed chip-to-chip interconnects, and high-speed sampling. The light absorption enhancement makes the MSM-PDs an ideal candidate due to their excellent performances in detection, especially in satisfying the high-speed or high-performance device requirements. The nano-grating assisted MSM-PDs are preordained to be decorous for many emerging and existing communication device applications. There have been a significant number of research works conducted on the implementation of nano-gratings, and still, more researches are ongoing to raise the performance of MSM-PDs particularly, in terms of enhancing the light absorption potentialities. This review article aims to provide the latest update on the exertion of nano-grating structures suitable for further developments in the light absorption enhancement of the MSM-PDs. Full article

The metal-assisted chemical etching (MACE) technique is commonly employed for texturing the wafer surfaces when fabricating black silicon (BSi) solar cells and is considered to be a potential technique to improve the efficiency of traditional Si-based solar cells. This article aims to review the MACE technique along with its mechanism for Ag-, Cu- and Ni-assisted etching. Primarily, several essential aspects of the fabrication of BSi are discussed, including chemical reaction, etching direction, mass transfer, and the overall etching process of the MACE method. Thereafter, three metal catalysts (Ag, Cu, and Ni) are critically analyzed to identify their roles in producing cost-effective and sustainable BSi solar cells with higher quality and efficiency. The conducted study revealed that Ag-etched BSi wafers are more suitable for the growth of higher quality and efficiency Si solar cells compared to Cu- and Ni-etched BSi wafers. However, both Cu and Ni seem to be more cost-effective and more appropriate for the mass production of BSi solar cells than Ag-etched wafers. Meanwhile, the Ni-assisted chemical etching process takes a longer time than Cu but the Ni-etched BSi solar cells possess enhanced light absorption capacity and lower activity in terms of the dissolution and oxidation process than Cu-etched BSi solar cells. Full article

Metallic thin-film materials and nanoparticles (mainly silver (Ag)-based) are recently being used in many nano-technological applications, including sensors, reflective heat-mirror coatings, and antibacterial coatings. The physical vapor deposition technique has attracted significant attention for Ag-based nanocomposites with tailoring of the structural and optical properties of metallic thin films, thus allowing for further improvements and application possibilities in various existing fields, namely electronics, catalysis, magnetics, and optics, alongside the environment and health and new emergent fields, particularly thin-film coatings. This study highlights the preparation, characterization, properties, and possible future application directions of several types of silver (Ag)-based nanocomposite thin films prepared by using physical vapor deposition techniques. The high-temperature (above 300 °C) heat-treated composite layer shows significant spectral shifts; however, distinguishingly notable sizes of nanoparticles are not observed, which indicates that this newly developed composite material can be useful for various coating applications. Full article

Aesthetic appearance of building-integrated photovoltaic (BIPV) products, such as semitransparent PV (STPV) glass, is crucial for their widespread adoption and contribution to the net-zero energy building (NZEB) goal. However, the visual distortion significantly limits the aesthetics of STPV glass. In this study, we investigate the distortion effect of transparent periodic-micropattern-based thin-film PV (PMPV) panels available in the market. To minimize the visual distortion of such PMPV glass panel types, we design and develop an aperiodic micropattern-based PV (APMP) glass that significantly reduces visual distortion. The developed APMP glass demonstrates a haze ratio of 3.7% compared to the 10.7% of PMPV glass. Furthermore, the developed AMPV glass shows an average visible transmittance (AVT) of 58.3% which is around 1.3 times higher than that of AMPV glass (43.8%). Finally, the measured CIELAB values (L* = 43.2, a* = −1.55, b* = −2.86.) indicate that our developed AMPV glass possesses excellent color neutrality, which makes them suitable for commercial applications. Based on the characterization results, this study will have a significant impact on the areas of smart window glasses that can play a vital role in developing a sustainable environment and enhancing the aesthetical appearance of net-zero energy buildings (NZEB). Full article

The reliability of photovoltaic (PV) modules operating under various weather conditions attracts the manufacturer’s concern since several studies reveal a degradation rate higher than 0.8% per year for the silicon-based technology and reached up to 2.76% per year in a harsh climate. The lifetime of the PV modules is decreased because of numerous degradation modes. Electromigration and delamination are two failure modes that play a significant role in PV modules’ output power losses. The correlations of these two phenomena are not sufficiently explained and understood like other failures such as corrosion and potential-induced degradation. Therefore, in this review, we attempt to elaborate on the correlation and the influence of delamination and electromigration on PV module components such as metallization and organic materials to ensure the reliability of the PV modules. Moreover, the effects, causes, and the sites that tend to face these failures, particularly the silicon solar cells, are explained in detail. Elsewhere, the factors of aging vary as the temperature and humidity change from one country to another. Hence, accelerated tests and the standards used to perform the aging test for PV modules have been covered in this review. Full article

We propose an all-dielectric magneto-photonic crystal with a hybrid magneto-optical response that allows for the simultaneous measurements of the surface and bulk refractive index of the analyzed substance. The approach is based on two different spectral features of the magneto-optical response corresponding to the resonances in p- and s-polarizations of the incident light. Angular spectra of p-polarized light have a step-like behavior near the total internal reflection angle which position is sensitive to the bulk refractive index. S-polarized light excites the TE-polarized optical Tamm surface mode localized in a submicron region near the photonic crystal surface and is sensitive to the refractive index of the near-surface analyte. We propose to measure a hybrid magneto-optical intensity modulation of p-polarized light obtained by switching the magnetic field between the transverse and polar configurations. The transversal component of the external magnetic field is responsible for the magneto-optical resonance near total internal reflection conditions, and the polar component reveals the resonance of the Tamm surface mode. Therefore, both surface- and bulk-associated features are present in the magneto-optical spectra of the p-polarized light. Full article