A recently developed class of carbon nanomaterials, known as graphene quantum dots (GQDs), has evolved, exhibiting exceptional electrical, optical, and chemical properties. In‐depth studies of GQDs have concentrated on modifying these features through doping and codoping techniques, opening up new device applications. A review on the exploration of their numerous applications in environmentally friendly and sustainable energy technologies is presented here. The doping techniques that are used to modify the electrical performance characteristics of GQDs are presented. Doping with nitrogen, sulfur, boron, and phosphorus is a commonly utilized method for modifying the bandgap of GQDs, increasing the charge carrier mobility, and enhancing their electrocatalytic activity. Codoping, a more sophisticated technique that involves introducing many dopants at once to produce synergistic effects, is investigated in detail. As dopants and codopants can encourage charge separation and boost catalytic activity for environmental remediation and hydrogen production, GQDs have also shown outstanding performance in sustainable devices. In addition, GQDs have found use in energy storage, in which they are used as supercapacitor electrode materials to increase their energy density and cycle life. Their exceptional electrocatalytic characteristics, attained through doping and codoping, have created opportunities for catalysts in fuel cells, enabling efficient energy conversion. The importance of GQDs in sensing and biosensing applications is explained. GQDs are poised to play a crucial role in the creation of novel solutions that address urgent global needs in energy, the environment, and healthcare.

In the area of photovoltaics, monocrystalline silicon solar cells are ubiquitously utilized in buildings, commercial, defense, residential, space, and transportation applications throughout the world. Their performance is impeded by the heating of the cells during their interaction with the incident solar radiation. The development of reliable computer simulations that effectively model the thermal response of monocrystalline silicon solar cells is critical for their design, fabrication, and utilization. This work employs a novel computer simulation to incorporate the optical, electrical, and thermal properties of silicon in the thermal analysis of silicon solar cells. After establishing the theoretical principles and the values of these properties, the results of the simulation are compared with other established studies. The analysis shows that the percentage difference in solar cell temperatures between simulation and literature is within a range of 0.354–0.487

This work investigates the temperature-dependent performance of three homojunction solar cells composed of silicon, gallium arsenide, and indium phosphide, using the open-source simulation software PC1D. Emitter layer thicknesses ranging from 0.01 to 1 $$\upmu$$ μ m were modeled across a temperature range of 273–373 K. The key photovoltaic parameters—short-circuit current density ( $$J_{\textrm{sc}}$$ J sc ), open-circuit voltage ( $$V_{\textrm{oc}}$$ V oc ), and conversion efficiency ( $$\eta$$ η )—were extracted to assess their thermal sensitivity. The results show that $$J_{\textrm{sc}}$$ J sc remains largely invariant with temperature, while $$V_{\textrm{oc}}$$ V oc declines approximately linearly, driving the observed reduction in efficiency, $$\eta$$ η . Silicon exhibited the steepest thermal degradation, with $$\eta$$ η decreasing from 21.8 to 13.5%. GaAs and InP demonstrated greater thermal stability, with $$\eta$$ η decreasing from 26.6 to 20.2% and 27.2 to 20.5%, respectively. Decreasing efficiencies were observed for all three cell configurations with increased emitter layer thickness. The greater temperature sensitivity of Si is attributed to stronger non-radiative recombination and phonon-assisted transitions characteristic of its indirect bandgap. Additional simulations on the impact of increasing surface recombination velocity and bulk carrier lifetime were carried out, indicating optimum performance at high lifetimes and low recombination velocities. These findings emphasize the advantages of direct bandgap materials for high-temperature photovoltaic applications and the efficacy of PC1D in explicating different material behaviors.

Magnetotactic bacteria are a diverse group of prokaryotes that create intracellular, membrane-bound organelles containing magnetic minerals known as magnetosomes. These minerals have a sdpecialized purpose with the use of mineral crystals such as magnetite (Fe3O4) or greigite (Fe3S4). Due to the stability of these crystal structures, the bacteria can orient themselves with the Earth’s geomagnetic field lines, functioning as compass needles to help them locate suitable environments to inhabit. The objective of this review, based on previous progressions in this area of study, is focused on presenting a comprehensive summary of MTB, its abundance and magnetosome formation. Moreover, the effects of certain environmental factors, as well as their significance and applications in material science, medicine, and biotechnology, are elucidated.

SiliconSilicon has been one of the most well-understood semiconductor materials in the literature. In spite of its mature know-how and technology, there is an absence of reliable values of its wavelength-dependent optical constants, i.e., refractive index and extinction coefficient of monocrystalline silicon in the wavelength range of 1–10 μm, in the literature. These values are critical to fully simulate, model, and understand the optical propertiesOptical properties of siliconSilicon in the infraredInfrared range of wavelengths, as well as to be able to design devices of interest, particularly in the infrared. In this study, the Forouhi–Bloomer dispersion equations have been utilized to predict the functions of the refractive index and extinction coefficient for the entire wavelength spectrum, including the sought 1–10 µm range. The calculated reflectivity and transmissivity are then analyzed and compared to prior findings in the literature.

Polymeric nitrogen (PN) is potentially a green catalytic material due to its Lewis base property, and a high-energy density material (HEDM) due to its considerable energy storage and the environment-friendly decomposition product, nitrogen gas. Most research has focused on theoretical studies and various structures were proposed, while a few successful experiments were carried out. Plasma technology, as a viable synthesis technique for materials, may provide new possibilities for polymeric nitrogen. In this review, the polymeric nitrogen study, the plasma technology, and its potential catalytic applications for polymeric nitrogen synthesis are reviewed and summarized. Polymeric nitrogen synthesis requires extremely high temperature and high pressure with traditional thermal method and is thermodynamically unstable, while some PNs exhibit excellent catalytic activity. High pressure, cations and substrates are important for polymeric nitrogen synthesis and stabilization. Plasma processes, full of energetically active particles, can operate under mild conditions and is very good for temperature-sensitive materials. Thus, plasma has a promising potential application for polymeric nitrogen synthesis. Proper precursors and substrates are important in order to increase products, which are necessary for further exploitation of polymeric nitrogen. With better understanding of the mechanism of plasma treatment, it will have wider applications.

The unique temperature-induced color changing properties of thermochromic materials make them of significant interest for applications in aerospace, anti-counterfeiting technology, construction, defense, drugs & pharmaceuticals, electronics, energy, food & agriculture, maintenance of infrastructure, materials processing & storage, military technology, optoelectronics, packaging, sensors, smart displays, textiles, thermal storage and transportation. Thermochromism occurs due to the following characteristics: (a) phase transitions in a compound (e.g. leuco dyes); (b) changes in ligand geometry or the number of solvent molecules in the coordination sphere (e.g. transition metal complex that derives its color from crystal field effects) and (c) complex factors in multicomponent mixtures. Thermochromic materials can be divided into several categories depending on their material properties and operating conditions. In recent years, numerous techniques have been used to synthesize thermochromic materials for a variety of purposes and applications. This review summarizes the various mechanisms of thermochromism, their classification, preparation and applications and discusses future development trends.

Traditionally, most of the mechanically driven systems utilize contact-dependent approaches. They have hosts of defects, including the need for lubrication to minimize friction, noise management, and a restricted operating life. The magnetic augmentation of existing devices within a mechanical system can resolve these issues by introducing a near-contactless method of operation. The design in focus is fundamentally a piston-styled shock absorberShock absorber that is capable of generating energy as a product of applied force. The system absorbs shock in two separate manners. The first is due to a series of repelling magnets oriented on two separate plates that oscillate in closeness depending on the applied force. The second is via the internal section of the piston, where an incompressible fluid is forced to flow through small holes in a magnetically fitted oscillating plate. By placing multi-layered, enameled copper coilsCoil surrounding the magnets’ direction of translation in both methods of shock absorption, electric currents can be generated thus inducing passive energy generation as a product of shock absorption. In addition, this system is constructed to be variably recursive; in essence, any number of devices can be oriented, so they perform together with small variations in structure depending on the location of each device. The current prototype focuses on a vertically recursive model for applications concerning constrains in a horizontal surface area.

The utilization of renewable sources of energy is of significant interest today. This is particularly the case due to the growing interest in addressing global warming, carbon footprint and the associated challenges for the environment. In this context, the enhanced use of solar panels is relevant and timely. With a view to understand and appreciate the fundamentals of the workings of the solar panels and the influence of the outdoor weather-related parameters on their operational characteristics, a study is presented in this paper. A detailed procedure for performance measurement of PV modules in outdoor conditions is reported. Improvement in the precision of outdoor performance measurements of photovoltaic (PV) modules is investigated for a wide range of outdoor conditions. A comparative performance evaluation of the currently available PV modules under the influence of humidity, irradiance and particle radiation is presented. PV parameters show strong dependence on these outdoor conditions. The instability in solar cell modules when reacting with water or under high humidity inhibits the high performance of solar cell modules. Irradiation results depict that the silicon-based PV modules show a decreasing trend of power conversion efficiency with increasing solar irradiance. The efficiency increases with increased solar irradiance for CdTe, GaAs and CIGS solar cells in the irradiance range of 200 to 1000 W•m-2. Tandem and multi-junction solar cells exhibit a high-power conversion efficiency when the solar irradiance increases from 0 - 70 suns. Perovskite solar cells have better particle radiation tolerance than silicon, III-V and CIGS solar cells. The shading problem is discussed briefly for solar cell modules. This study is aimed to provide valuable and comparable information on the degradation performance of solar cells as function of humidity, irradiance and particle radiation, and serves as the basis for future development.

A review of the current developments in the synthesis of graphene fragments of porous carbon material by utilizing green precursors in the form of graphene quantum dots (GQDs) and their applications in energy storage devices such as supercapacitors, batteries, fuel cells, and solar cells is presented in this study. Two different approaches, including top‐down and bottom‐up, are discussed. The experimental approaches include hydrothermal or solvothermal method, microwave‐assisted method, electrochemical oxidation, controllable synthesis, oxidative cleavage, and carbonization from small molecules or polymers. The advantages and disadvantages of the green synthesis of GQDs are discussed. Current challenges and prospective applications of GQDs in energy‐related areas are presented. A brief outlook is provided for addressing the problems for further advancement of GQDs. It is anticipated that the results discussed in this study will lead to a better understanding of GQDs as well as their significant roles in developing innovative strategies and applications.

A metal/polymer/metal sandwich can combine the benefits of individual materials with desirable properties and functionalities. They are commonly used in aviation and automotive industries. They provide the desired mechanical strength, high elasticity, and light weight, which also makes them suitable for biomedical prostheses by bridging the gap between implants and human tissues. However, epoxy resins, generally used for bonding the individual layers in industrial applications, are detrimental to biomedical applications. Therefore, it is essential to replace epoxy resins with a biocompatible interlayer to ensure both biocompatibility and faultless adhesion by a strong covalent bond. The interest in this material configuration has surged since the early work by Palkowski in this field. This study offers an encompassing view of metal/polymer/metal sandwich systems and delves into a comprehensive discussion about their diverse applications.

Magnetic field assisted assembly techniques are gaining acceptance as a novel concept in the intricate placement of devices on substrates at the wafer-level. The research into such innovative techniques requires creation of a uniform magnetic field to begin with. This will require a large array of milli-scale electromagnets needing a large number of miniature electromagnetic coils of uniform size. Such coils are required in varying lengths from 5.0 to 25.0 mm, core diameters ranging from 0.5 to 2.0 mm and wire sizes ranging from AWG 24 to 32. Dual-layer coils will more than double the magnetic field strength compared to monolayer coils. In addition, dual-layer coils will result in a coil structure in which the leads will terminate at the same end of the coil.

This chapter provides an introduction to the basics of microbolometers. Their principle of operation and structural design are briefly described. The classification and types of microbolometers are presented. The methods of fabrication of microbolometers are illustrated. 2D materials for the fabrication of microbolometers are introduced.

A brief history of infrared radiation is presented. Infrared detectors and their classification are introduced in this chapter. Their mechanism and the associated materials that are utilized in the fabrication of microbolometers are briefly discussed. Their historical developments and timeline are presented.

This chapter presents a brief history of temperature measurements. The fundamental principles of IR photon detectors and thermal detectors are described. It is followed by a discussion of the various materials that are utilized in the research, development, and manufacture of infrared photon detectors and thermal detectors. The properties and processing of some of these materials are discussed.

The fundamental mathematical relations that govern the performance and figure of merit of microbolometers are described in this chapter.

The ability to maximize the reflectance losses due to silicon is of paramount importance in the design, fabrication, and operation of silicon solar cells. Optimally designed antireflection coatings are required to improve photon collection in solar cells. For efficient performance, solar cells need to have low reflectance and high absorptance in the visible to near-infrared region. In this study, reflectance due to varying thicknesses of various dielectrics such as aluminum oxide (Al2O3), silicon dioxide (SiO2), titanium dioxide (TiO2), magnesium fluoride (MgF2), and silicon nitride (Si3N4) has been simulated in the range of visible to near infrared by mathematical modelling using MATLAB simulations. The results of the evolution of spectral properties, as a function of dielectric material thickness, on silicon substrates are presented.

In this study, the fabrication and characterization of Nb-doped strontium cobaltite, SrCo0.9Nb0.1O3-delta (SCN), with a significant concentration of oxygen vacancies, as a charge storage material, prepared using sol-gel method, is reported. The results obtained show that the diffusion of oxygen ions is a rate limiting factor for charge storage. The perovskite material, niobium doped strontium cobalitite, on nano graphene sheets such as SCN@GQDs, has been prepared. The Graphene Quantum Dots (GQDs) have been synthesized by using a facile hydrothermal method. The morphology of SCN@GQDs was characterized by FESEM, and TEM. Additional characterization techniques such as PXRD, Raman Spectroscopy, FTIR, TGA/DTA, and BET were performed to observe the structure, porosity, functional groups, defects and thermal behavior of the material. The prepared SCN@GQDs act as an effective electrode material and exhibit high energy density. These SCN@GQD electrodes have been investigated for their electro-chemical properties. The specific capacitance of the synthesized perovskite materials, at 0.1 Ag-1 for supercapacitor, is higher than those of GQDs and SCN due to the improved conductivity, presence of oxygen vacancies and fast ion diffusion between the working electrodes and electrolyte. These properties of SCN@GQD perovskite material, with nanographene sheets, for boosting the capacity of electrodes, provide excellent opportunities for applications in supercapacitors. This perovskite material is superior in comparison to other candidates due to its larger oxygen vacancy concentration and higher oxygen-ion mobility.