Carbon nanotube–metal oxide (CNT–MO) composites have attracted considerable attention as advanced hydrogen storage materials because of their synergistic structural, electronic, and catalytic properties. Their strong interfacial interactions enhance hydrogen adsorption–desorption kinetics, storage capacity, reversibility, and overall material stability. This review critically examines recent progress in CNT–MO composites for hydrogen storage, with particular emphasis on the relationship between synthesis strategies, interfacial engineering, structural characteristics, and hydrogen storage performance. Various hydrogen adsorption mechanisms, including physisorption, chemisorption, Kubas interaction, and hydrogen spillover, are comparatively discussed. The role of CNT–MO interfaces in governing hydrogen uptake and reversibility through the hydrogen spillover mechanism is critically discussed. Different synthesis approaches, such as chemical vapor deposition, sol–gel processing, ultrasonication, atomic layer deposition, and microwave-assisted synthesis, are systematically evaluated in relation to nanoparticle dispersion, oxide crystallinity, defect formation, and interfacial bonding. In addition, advanced characterization techniques used to establish structure–activity–performance relationships are critically analyzed. Different classes of metal oxides, including transition-metal oxides, alkaline-earth oxides, rare-earth oxides, and mixed-metal oxide systems, are comparatively assessed for hydrogen storage capacity, adsorption/desorption kinetics, cycling stability, and catalytic efficiency. The review demonstrates that hydrogen-storage performance in CNT–MO composites is strongly influenced by interfacial bonding, oxide thickness, nanoparticle morphology, defect density, oxygen vacancies, and metal oxide loading. Current limitations, including low hydrogen storage capacity, poor reversibility, nanoparticle agglomeration, limited reproducibility, and scalability challenges in industrial-scale production, are also discussed. Finally, future research directions focusing on interface engineering, defect tuning, oxygen-vacancy control, computational modeling, and scalable fabrication strategies are highlighted to accelerate the practical development of CNT–MO composites for hydrogen storage technologies.

Thin-film photovoltaic technologies such as perovskite, CIGS, CdTe, and organic solar cells have gained considerable attention due to their potential for low-cost, flexible, and lightweight energy conversion solutions, necessitating advanced components to optimize device efficiency and stability. A complex component in these devices is the electron transport layer (ETL), which governs charge extraction and recombination dynamics, directly impacting overall performance. Despite numerous advances, there remains a lack of unified understanding of ETL materials and interface engineering, highlighting a research gap in cross-technology comparative studies and universal design principles. This review addresses this gap by systematically analyzing ETL materials, interface modification strategies, and deposition techniques reported in recent literature across multiple thin-film PV systems. Employing a comprehensive cross-technology approach, the study synthesizes experimental, theoretical, and practical insights to identify emerging materials. Key findings emphasize the effectiveness of interface engineering methods such as surface passivation, energy level alignment, and self-assembled monolayers in enhancing charge transport and reducing recombination losses. This work significantly provides a framework to overcome challenges related to scalability, cost, and compatibility with flexible and tandem architectures, thereby guiding future development of universal ETLs and innovative design strategies to accelerate the commercialization and performance of thin-film solar cells.

The rapid development of photovoltaic (PV) systems has made them an important component of the global clean energy strategy. However, the intermittency and non-linear characteristics of photovoltaic (PV) output remain major challenges for stable renewable energy utilization. This study proposes an adaptive improved particle swarm optimization (IPSO)-based maximum power point tracking (MPPT) strategy integrated with hybrid energy storage coordination for photovoltaic systems. The IPSO introduces adaptive inertia adjustment, velocity clamping, and stagnation reinitialization, which improve the convergence robustness under dynamic irradiance and temperature conditions. The algorithm was benchmarked against Perturb & Observe (P&O), Incremental Conductance (INC), and standard PSO using convergence speed, ripple, bus voltage stability, and battery stress as performance indicators. The results show that IPSO significantly reduces settling time compared with conventional PSO, minimizes steady-state oscillations, and enables coordinated battery-supercapacitor operation, which is expected to mitigate battery stress under dynamic conditions. This demonstrates IPSOs' potential as a multi-objective optimization tool for PV-HESS systems, offering practical insights for intelligent energy management in microgrids and renewable networks.

Building-integrated photovoltaics (BIPV) are becoming a more popular source of renewable energy. It is an on-site renewable energy source within buildings but has limited growth due mainly to lifespan issues throughout the entire life cycle from manufacturing to design, installation, electrical integration, operation, and end of life. This paper reviews the climate-driven deterioration mechanisms of BIPV, including thermal cycling, moisture ingress, atmospheric pollutants, wind loads, etc. They relate these climate-driven deterioration mechanisms to BIPV performance deterioration, energy yield reductions, safety concerns related to energy loss, and long-term reliability of BIPV systems across all parts of the BIPV life cycle. Through many international case studies and recent research results, this review identified major knowledge gaps and bottlenecks in the deployment of BIPV and assessed various strategies for improving the durability, stability/performance, and sustainability of BIPV systems in all weather conditions, such as climate-adjusted materials, better electrical architecture, predictive maintenance, and circular design at the end of life. By integrating the material, electrical, and operational aspects of BIPV, this paper provides an organized approach to increasing the durability, stability/performance, and sustainability of BIPV systems in each climate setting.

Hybrid power systems have evolved into a vital component of contemporary power networks, finding application in various domains ranging from automotive to small-scale off-grid setups. Their purpose is to optimize the utilization of diverse energy sources. This study delves into the efficacy of integrating ultra-capacitors and batteries synergistically. Employing a multi-input converter to drive a variable DC load, the aim is to minimize losses and expenses. In the proposed configuration, a single inductor is utilized, facilitating the integration of a variable array of distributed energy sources. Notably, this converter expedites ultra-capacitor (UC) charging by offering a low inductance pathway, distinguishing it from conventional multi-input DC-DC converters. This proposed topology is bidirectional and adaptable to accommodate varying numbers of energy sources. The obtained numerical results reveal the converter’s effectiveness in stabilizing output voltage and current, making it suitable for multiple applications like electric vehicles, fuel cell systems, and renewable energy integration. Additionally, in the proposed topology, the results showed that it could charge a 2000F UC from a 300V source from 40% to 100% in just 400s and from a 150V battery from 20% to over 90% in just 200s due to the single inductor present in the charging path. Moreover, the load voltages are below 2% in all operational modes when either one or two sources are driving the load. Future research may focus on refining control algorithms to further enhance system efficiency and expand its applicability across different sectors.

Clean, inexpensive, and renewable energy sources with zero adverse environmental impact are essential for long-term sustainability. Implementing waste-to-energy (WtE) technologies has been suggested to improve solid waste management and promote the development of clean and sustainable urban environments. This involves the retrieval of waste materials and their conversion to electricity. By 2050, the global rate of Municipal Solid Waste (MSW) production is anticipated to rise to 2.01 billion tonnes annually. This study evaluated various WtE technologies that have been developed to date. These technologies can be categorized into three groups: thermochemical methods (incineration, pyrolysis, and gasification), biochemical methods (anaerobic digestion and landfilling), and hybrid waste-to-energy systems. Additionally, the discussion touched upon various environmental aspects, highlighting the advantages of reducing COX, NOX, SOX, furans, and dioxin emissions. Furthermore, this study thoroughly describes the economic impact of various steps on a WtE plant. It also discusses policy and regulatory frameworks, namely availability, affordability, rights, social aspects, and environmental issues, that aim to incorporate principles of ethics, justice, planning, and decision-making when evaluating different aspects of energy systems.

Silver-based metallic thin-film nanostructured materials are extensively utilized in advanced technological applications, including sensors, energy-efficient coatings, antibacterial coatings, and optical filters. Physical vapor deposition has emerged as a significant technique for synthesizing silver (Ag)-based nanocomposites, enabling the modification of structural and optical properties of thin metallic films. This advancement facilitates material development and applications in electronics, catalysis, magnetics, optics, environmental and health sectors, and specialized optical coatings. Research has demonstrated the successful integration of various nanomaterials with Ag matrices, resulting in multifunctional thin-film systems. Ag-based nanocomposite thin films exhibit exceptional electrical conductivity, rendering them suitable for electronic and optoelectronic devices. Their unique optical properties enable applications in advanced photonics, spectroscopy, and imaging technologies. These films also demonstrate potential in catalysis, power conversion and storage, environmental remediation, and chemical sensing. The incorporation of antimicrobial agents presents opportunities for biomedical applications. This review aims to comprehensively examine the synthesis, characterization, and potential applications of physically vapor-deposited Ag-based nanocomposite thin films, highlighting their promising future in various fields.

The increasing global adoption of electric vehicles (EVs) has led to a growing demand for a cost-effective and reliable charging infrastructure. This study presents a novel data-driven approach to assessing EV station performance by analyzing power consumption efficiency, station utilization rates, no-power session occurrences, and CO2 reduction metrics. A dataset of 17,500 charging sessions from 305 stations across a regional network was analyzed to identify operational inefficiencies and opportunities for infrastructure optimization. Results indicate a strong correlation between station utilization and energy efficiency, highlighting the importance of strategic station placement. The findings also emphasize the impact of no-power sessions on network inefficiency and the need for real-time station monitoring. CO2 reduction analysis demonstrates that optimizing EV charging performance can significantly contribute to sustainability goals. Based on these insights, this study recommends the implementation of predictive maintenance strategies, real-time user notifications, and diversified provider networks to improve station availability and efficiency. The proposed data-driven framework offers actionable solutions for policymakers, charging network operators, and urban planners to enhance EV infrastructure reliability and sustainability.

This study investigates the influence of magnesium (Mg) doping on ZnO thin films prepared through spin coating to enhance their efficiency and stability in perovskite solar cells (PSCs). The incorporation of Mg significantly enhanced charge transport, reduced recombination losses, and enhanced overall device stability. The structural, optical, morphological, and electrical properties were investigated using UV-Vis spectroscopy, field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and Hall Effect measurement. SCAPS-1D simulation software was utilized to study the performance of the solar cell under different Mg doping concentrations in order to determine the optimum conditions for the maximum power conversion efficiency (PCE). Simulation findings exhibit adequate utility regarding power conversion efficiency (PCE) gain of around 21.89% with optimized Mg doping, which is equivalent to undoped ZnO film performance. While the PEC performance of the doped ZnO is comparable to that of its undoped counterpart, this study reveals notable improvements in optical tunability, charge transport properties, and, in simulations, reduced defect-related trap densities that suggest more favorable band alignment. Simulation results show enhanced PCE of 21.89% under optimal Mg doping compared to undoped ZnO, along with substantial band alignment adjustments, optical tunability, and charge transport. While efficiency enhancements are marginal, these developments signify future possibilities toward enhanced device longevity. Results displayed are SCAPS-1D simulation-based, and experimental validation is required to determine device-level stability and performance. It should be noted that any additional device fabrication or physical characterization are not possible at this time; hence, conclusions are limited to the simulation results and film-level characterizations given in this document.

The focus of this work is on the optimization of an all-photovoltaic hybrid power generation systems for energy-efficient and sustainable buildings, aiming for net-zero emissions. This research proposes a hybrid approach combining conventional solar panels with advanced solar window systems and building integrated photovoltaic (BIPV) systems. By analyzing the meteorological data and using the simulation models, we predict energy outputs for different cities such as Kuala Lumpur, Sydney, Toronto, Auckland, Cape Town, Riyadh, and Kuwait City. Although there are long payback times, our simulations demonstrate that the proposed all-PV blended system can meet the energy needs of modern buildings (up to 78%, location dependent) and can be scaled up for entire buildings. The simulated results indicate that Middle Eastern cities are particularly suitable for these hybrid systems, generating approximately 1.2 times more power compared to Toronto, Canada. Additionally, we predict the outcome of the possible incorporation of intelligent and automated systems to boost overall energy efficiency toward achieving a sustainable building environment.

In the past few years, there has been notable interest in the advancement of colored photovoltaic (PV) modules. This attention is driven by their visual attractiveness and the opportunities they offer for integrating PV technology into diverse applications. However, limited color options and low efficiency restrict the widespread application of PV modules. This research introduces a targeted micropatterning strategy aimed at improving the efficiency and visual appeal of colored photovoltaic (PV) modules. This approach entails the selective elimination of black pixels from a multicolored pattern. By doing so, the surface area of the PV module is augmented, fostering enhanced light absorption and subsequently boosting output power. This study compares the performance of a selective micropatterned-based colored PV (SMPCPV) module with a reference black PV module, multicolored PV (MCPV), and a non-selective micropatterned-based colored PV (MPCPV) module. The characterization was performed in the outdoor environment where the result shows that the photoconversion efficiency (PCE) of the SMPCPV module is 11.36

Zinc-oxide (ZnO) nanostructures including nanorods are currently considered pioneer research of interest worldwide due to their excellent application potentials in various applied fields including the improvement of conversion efficiency of photovoltaics solar cells (PSC). We report on the growth and morphological properties of zinc oxide (ZnO) nanorods grown on the surface of plain zinc (non-etched and chemically etched) plates by using a simple, economical, and environment-friendly technique. We apply the hot water treatment (HWT) technique to grow the ZnO nanorods and vary the process parameters, such as temperature and the process time duration. The morphological, and elemental analysis confirms the agglomeration of multiple ZnO nanorods with its proper stoichiometry. The obtained nanostructures for different temperatures with different time duration show the variation in uniformity, density, thickness, and size of the nanorods. The ZnO nanorods produced on the etched zinc surface are found thicker and uniform as compared to those grown on the non-etched zinc surface. This chemically etched Zinc plate preparation can be an easy solution to grow ZnO nanorods with high density and uniformity suitable for the development of next-generation PSCs with higher conversion efficiency.

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.

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.

This research focuses on simulation studies that explore innovative approaches to energy conservation to empower remote areas through the implementation of sustainable power solutions. The objective is to address the energy needs of underserved regions that lack access to conventional power grids. By utilizing simulation techniques, this study aims to predict, analyze, and model various strategies for achieving the best and most cost-effective pathways of energy conservation and sustainable power generation in remote areas. This study assesses the performance, feasibility, and potential impact of each approach in terms of energy efficiency, cost-effectiveness, and environmental sustainability. The results of the simulation studies highlight the potential benefits of innovative energy conservation strategies in remote areas, including reduced energy costs, improved energy access, and enhanced socio-economic development. Furthermore, the research sheds light on the challenges and opportunities associated with the adoption and implementation of these approaches, guiding for overcoming barriers and maximizing the impact of sustainable power solutions.

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.

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 (Isc), open-circuit voltage (Voc), maximum power (Pmax), 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.

Microchannels based on microelectromechanical systems (MEMS) have received a lot of interest in the microfluidics and biomedical fields over the past forty years.While their applications have been multifarious, a comprehensive literature review focusing on their design, type, and applications is not currently present in the literature.Researchers working on these elements of microchannels will gain targeted knowledge from the current review on microchannels.Due to its advanced properties, flexibility of mass, and small size, microdevice demand has been rising quickly, particularly in industrial applications.The classification of microchannels and their uses are the main focus of this work.These include but are not limited to molding, electroplating, lithography, lab-ona-chip, micromolding, micromachining, micromilling, laser ablation, lithography, microcontact printing (µcp), hot embossing, electrochemical micromachining (EMM), and etching.In addition, numerous hybrid techniques for microchannel manufacturing have been reported.So, in essence, this review offers a range of advancements in microchannel manufacturing.The review also attempts to present a qualitative analysis describing the various methodologies associated with microchannels in terms of their design, shape, and flow regimes for applications such as pressure drop and transfer of heat prediction.Additionally, depending on the precise uses needed, a number of materials, including but not limited to ceramics, silicon, metals, and polymers, are utilized in the manufacture of microchannels.On metallic substrates, polymers such as silicon, glass, and polymeric materials are used.The biomedical industry uses polymeric and glass substrates instead of silicon substrates, which are used for mechanical engineering and electronic applications.In addition to outlining methods for choosing the best kind of microchannel, this paper also suggests important directions for the future.

Modern civilization demands energy, and the energy demand is increasing almost every day all over the world. The dependency on conventional energy resources including fossil fuel, oil, gas, coal etc. are not in favor of having sustainable global earth. For this reason, renewable or clean energy is one only option while acquiring energy from the abundant sunlight is the best and cost-effective choice. Photovoltaic (PV) panels are widely employed as clean and environmentally acceptable energy sources. However, due to restrictions in PV cells, the sun’s full energy cannot be turned into electricity. In this paper, we discuss how to improve the conversion efficiency of GaAs solar cells by optimizing the design and performance of nanostructured gratings. We design, simulate, and analyze the performance of three alternative arrangements of periodic nanostructures with varied pitches and heights using the finite difference time domain (FDTD) approach. Different geometries of nanostructures behave differently towards impinging the light, as the simulation results.

Bangladesh's railway system mostly uses typical manual railway crossing technique or boom gates through its 2,955.53 km rail route all over the country. The accidents are frequently happening in the railway crossings due to not having obstacle detectable and quickly operating gate systems, and also for fewer safety measures in the railway crossing. Currently, there are very few automatic railway crossing systems (without obstacle detectors) available, however, 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 the power generation of 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 in the railway crossing points. We design to use two infrared (IR) sensors to operate the railway crossing systems which will be controlled by the Arduino Uno. This newly designed level crossing system will be run with the help of sustainable renewable energy which is cost-effective, eco-friendly, and apply 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 results of several renewable energy sources including a hybrid system and optimized the Levelized Cost of Energy (LCOE), and the payback periods.