Proceedings of the 3rd International Conference on Materials Chemistry and Environmental Engineering (CONF-MCEE 2023), Part II
Ioannis Spanopoulos, University of South Florida
Niaz Ahmed, FAST-NUCES, Islamabad
Sajjad Seifi Mofarah, University of New South Wales
Recently, ferroelectric material is playing a more and more important role in the applications of semiconductor devices, especially in random access memory(RAM) devices, and transistors. Compared with traditional flash memories, FRAMs have advantages such as low operation voltage, a huge number of writes, non-volatile properties, and high write speed. However, in the early stage, the main materials used to produce FRAMs are perovskites with crystal structures. Those materials like PbTiO3/PbZr0.3Ti0.7O3 are restricted by the size and the complementary-metal-oxide-semiconductor (CMOS) technology, which is the common technology used to process semiconductor materials. Hafnium oxide material is a newly discovered material with ferroelectricity when doped with Zirconium(Zr). The Hf0.5Zr0.5O2 thin film is an ideal material for FRAMs, which has a smaller size than perovskites FRAMs and is compatible with current CMOS technology, which means lower cost and higher performance. This article aims to explain some properties of hafnium oxide materials based on different aspects, like dopants, thickness, annealing, and electrodes, and elaborate on the advantages of FRAMs made by hafnium oxide materials.
Complementary metal oxide semiconductor (CMOS) devices are an important part of integrated circuit (IC), but in the application process, it has many reliability problems, such as negative-bias temperature instability (NBTI), electromigration (EM), time-dependent gate oxide breakdown (TDDB), hot carrier injection (HCI), etc. These reliability problems can affect the threshold voltage and mobility of the device. In order to improve the reliability of integrated circuits, these reliability problems are systematically studied in this paper.
Applying a tandem structure to silicon-based sub-cells is the most promising strategy for enhancing efficiency and overcoming the Shockley-Queisser limit, which is an intrinsic limitation of silicon-based solar cells. This study will begin with the various categories of tandem solar cells and then analyze the requirements for optimizing the overall conversion efficiency. Therefore, the characteristics of BaZrS3, a chalcogenide perovskite with high elemental abundance, exceptional photovoltaic properties as well as outstanding stability, are thoroughly evaluated and compared with other previously utilized materials for the top sub-cell. Finally, the most feasible approach for thin film growth which is physical vapor deposition is reviewed based on the available literature from bulk synthesis of BaZrS3. This evaluation may serve as a critical guideline for the future commercialization of BaZrS3.
Graphene quantum dots (GQDs) have recently been developed as promising interfacial engineering materials for modifying perovskite solar cells (PSC) surfaces due to their low toxicity and good charge mobility compared to other metallic-based quantum dots in semiconductors. However, the side effect of decorating PSC with GQD is that it creates more structural defects that might cause shallow trap states and non-radiative recombination, leading to decreased PSC performance. This paper reviews the impact of structural defects and trap state of GQDs and the combined corresponding influence on the performance of PSC based on thermally stimulated current (TSC) and density-voltage (J-V) plots. This paper then offers new guidelines to minimize the trade-off of GQD by suggesting a well-controlled fabrication process.
Among the wide range of third-generation photovoltaic power generation technologies, there is a widely used type of photovoltaic - heterojunction photovoltaic cells. Although each of the different types of heterojunction photovoltaics has been studied in depth, no one has considered the direct application of the different types of heterojunction photovoltaics at the application level. This paper introduces the composition and advantages of heterojunction photovoltaic cells, and briefly introduces graphene/n-type amorphous silicon heterojunction photovoltaic, organic compound/inorganic heterojunction photovoltaic, and inorganic/inorganic heterojunction photovoltaic represented by CuO and Zn2O, and summarizes the different photovoltaic conversion efficiencies, preparation methods, and other key information of these cells, and compares these information. In particular, whether the photovoltaic conversion efficiency can reach the shockley-queisser limit is examined. Among them, the photoconversion efficiency of graphene/n-type amorphous silicon heterojunction and simple metal oxide heterojunction was not very satisfactory, and finally the heterojunction PV cell constructed by the byorganic cavity-conducting material led by Graezel et al. was chosen among the different research directions of organic/inorganic heterojunction PV cells. Cavity-conducting material combined with a titanium dioxide nanofilm with adsorbed dye as a relatively ideal heterojunction PV cell for comparison was examined in this paper, which provides a proposal for the commercial development of new heterojunction PV cells in the future.
In recent years, major industries have been hit hard by the COVID-19 pandemic, and people have become more aware of issues such as environmental health. The development of computer programs, artificial intelligence (AI), has gradually entered the vision of researchers. The product of this technology can help people better manage and improve the current environmental conditions. This paper, through a method of literature review, aims to explain the development history of AI and its application in different fields such as the environment. Through the research, the paper concludes that artificial intelligence can observe in real time for long periods of time without getting tired like humans do. Based on the application of big data analysis and intelligent programs, artificial intelligence can make reasonable plans in a much shorter time than human beings. However, the solution is only based on the operation of the system. In the actual situation, there will be many obstacles. Therefore, it is still necessary for humans to make judgments based on the results of an operation rather than relying entirely on artificial intelligence. Complicated weather conditions can also make the results of the calculation inaccurate. So there will still be a need to evolve computer programs or for artificial intelligence to be able to calibrate the data it is monitoring from the past.
Various devices made of the third-generation semiconductor have been gradually applied to various fields with the rapid development of the third-generation semiconductor materials equipment, manufacturing technology, and device physics represented by SiC and GaN. Firstly, the characteristics of the third-generation semiconductors is analyzed in this paper. Compared with the first-generation and second-generation semiconductors, the third-generation semiconductor has a wider band gap width, higher breakdown electric field, higher thermal conductivity, higher electron saturation rate and more expensive price. Then this paper will talk about the application of the third-generation semiconductor. The third-generation semiconductor materials can be mainly used in three fields, which are photoelectric, microwave radio frequency and power electronics. In terms of the photoelectric aspect, this paper takes the blue LED as an example. The blue LED is produced because of the wide band gap of the third-generation semiconductor. In the microwave RF aspect, the paper takes the 5G communication system as an example. Third-generation semiconductors make the high-frequency, high-power devices needed for 5G communications systems. In the power electronics aspect, the paper cites new energy vehicles as an example. Third-generation semiconductor components have a number of features needed for new-energy vehicles. For example, third-generation semiconductors can work at high temperatures. Finally, this paper will introduce the development trend of it. In the future, larger wafers will become mainstream. The third-generation semiconductors will be used in more fields. In addition, the new material systems will gradually mature.
Beta-blockers are generally prescribed for cardiovascular treatment and sometimes as sedative drugs for professionals such as musicians and athletes, which can cause serious side and adverse effects when the dosage is high. Additionally, beta-blockers are maintained as prohibited drugs for athletes by World Anti-Doping Agency (WADA). It is urgent to develop quick, simple and affordable analytical tools for beta-blockers. Electrochemical sensors have been favored by researchers for their simplicity, portability and quick detection. Therefore, this review discusses the most common voltammetric sensors for beta-blockers, along with two important features for effective determination: sensitivity and selectivity, which are realized by chemically modified electrodes.
An innovative approach that blends nanotechnology technologies with supramolecular chemistry can accelerate the creation of complex nanoparticle-based goods, self-assembly is used in the production of nanoscale self-assembled systems with desired properties with great versatility and potential. One of the most intriguing classes of material that can be constructed by self-assembly is colloids which is widely used in many areas, especially in the pharmaceutical and industry.
In recent years, conductive polymer materials have become a hot topic in scientific research due to their wide applications. Conductive polymer materials are mainly divided into composite type and structural type. Due to the poor oxygen stability and mechanical properties in the air of the doped materials of the structural conductive polymer, its application is limited. However, the composite conductive polymer has become the most widely used conductive polymer material in the market because of its easy processing, wide application range, good corrosion resistance and the conductivity can change according to the electrochemical reversible reaction. In this paper, the composite conductive polymer materials with different doping types are reviewed, and their applications in the fields of stealth technology, battery materials, and sensors are studied. The research significance of this paper is to summarize the research progress of composite conductive polymer materials by scientists in various countries in recent years, and provide scientific and theoretical support for other researchers in this field.
With the increasingly serious problem of global warming and the growing scarcity of energy represented by oil, automobile development has reached a historical tipping point. Nowadays, the most popular solution is to use other clean and sustainable energy to replace current oil and natural gas, thereby addressing both environmental and energy shortage issues. Solar energy, as a "inexhaustible" source of energy, has made significant technological advances over the course of human history. There is, however, a gap in the application of solar energy technology in automotive technology. This paper uses COMSOL software to model the most commonly used solar panels and simulates and studies the streamline distribution, velocity distribution, pressure distribution, and stress distribution of the solar surface under high-speed movement of 90km/h. SoildWorks simulation is used to design a vehicle body structure for future solar cars based on these data. FLUENT software is used to simulate and study the streamline distribution and pressure distribution of the car body at a high speed of 90km/h. Finally, the design's logic and feasibility are validated. The fluids on the surface of a single solar panel and a vehicle body are simulated in this paper. Testing the pressure distribution and stress and strain tests can reveal the rationality and feasibility of the structural design.
In recent years, with the rapid development of social and economic development, scientific and technological progress, human production and living standards have achieved tremendous improvement, at the same time, a large number of exhaust gases and soot emissions have become important sources of pollution, industrial energy consumption and urban construction, etc. make China's air environment pollution problem increasingly serious. The air quality in China gradually presents regional pollution, especially in the Yangtze River Delta, Pearl River Delta, and Beijing-Tianjin-Hebei regions. This paper takes Shanghai as the research object and empirically analyzes the main influencing factors of its air quality, which can provide reference not only for managing the air quality of this city, but also for the air quality management of similar cities. This paper empirically investigates the influencing factors of air quality in Shanghai based on the Shanghai air quality monitoring data, including AQI (Air Quality Index) and PM2.5, PM10, NO2, CO, SO2 and O3 pollutant concentrations, released by the Shanghai Bureau of Ecology and Environment from January 2015 to October 2021. This paper uses the knowledge of econometrics to establish a multiple linear regression model with the help of RStudio, which is continuously estimated, tested and improved on the basis of the primary model to analyze the degree of influence of pollutants on AQI, and also to analyze the main pollutants affecting air quality by testing. The statistical results show that the primary air pollutants in Shanghai are O3 and NO2. Based on the analysis results, this paper puts forward corresponding suggestions about improving the air quality and protecting the ecological environment in Shanghai.
This paper’s primary purpose is to explore why the microstructure of synthetic block copolymers and natural spider silk is similar at the nanoscale. This paper analyses the main chain segments and secondary structures of natural spider silk, clarifies the aggregation order, and introduces the contribution of secondary systems to the properties of natural block copolymers. Secondly, combined with the synthesis mechanism of natural spider silk, this paper summarizes and analyzes the general process of the synthesized block copolymer. Finally, the conditions of self-assembly of artificial fragments to form the structure are analyzed by employing mean-field theory and a phase diagram. Natural and ideal synthetic spider silk block copolymers have high similarity in performance. To achieve this, scientists can only start from the primary segment to understand their arrangement order in the secondary structure. Then the influence of each block on the properties of the silk fiber is analyzed. At the same time, the size and shape of self-assembled block copolymers are controlled at the micro-scale, thereby changing their properties. The mechanism above shows that the synthesized spider silk block copolymer is similar to natural spider silk in microscopic morphology.
Situated in an area near the equator, Singapore has a promising potential to develop solar energy. And apart from solar energy, other types of renewable resources are relatively scarce in Singapore. As a result of the continuous supply of sunlight, as well as the silent operation, low maintenance costs, and environmental friendliness, solar was the best choice for developing renewable energy resources in Singapore. However, on account of the dense population and limited land resources, photovoltaic development is also facing some problems. And the use of the surrounding sea area to develop offshore photovoltaic is a very good option. This paper mainly discusses the current state of solar energy in Singapore and puts forward some future prospects for the development of offshore PV in Singapore. In general, the photovoltaic industry in Singapore has developed rapidly in recent years, but it can still only meet a small part of the demand for electricity. In the future, it should continue to vigorously promote its development, especially in the offshore photovoltaic sector, which deserves more attention.
The study and implementation of clean, efficient, and long-lasting forms of new energy are currently the focal point of scientific inquiry all over the globe. Carbon nanotubes are excellent hydrogen storage materials, catalyst carriers, and electronic device components due to their outstanding electrochemical properties and near-ideal one-dimensional nanospace. The periodic structure of the crystal and the surrounding charge distribution can be effectively altered by constructing defects in electrode materials or electrocatalysts, as has been demonstrated in a large number of recent studies. This paper provides a summary of the interaction of carbon-carbon double bonds, an analysis of the electrochemical properties of single-wall carbon nanotubes with various chiral graphene defects, and an investigation of the electrochemical properties of double-walled carbon nanotubes with blade dislocation, spiral dislocation, and their composite structures, all based on molecular dynamics simulation.
In recent years, the preparation of polymer micelles and self-assembled nanomaterials by amphiphilic block copolymers has attracted great interest and has now become a research hotspot in the field of polymer science. Based on the self-assembly technology of block compounds, this paper introduces how self-assembly technology can play a role in the clinical environment, especially for the treatment of tumors and cancer, and controlled drug release. Finally, the related challenges and opportunities for self-assembled nanoparticles are described and prospected. Currently, although block copolymers have great performance in many fields, it is difficult to summarize one or a series of regular methods for the preparation of block copolymers and we also did not find a preparation method suitable for industrial production and wide application.
Graphene was originally found as a thin sheet structure. Researchers have expanded their studies to include this 2D carbon structure in recent years. The paper aims to give a review of the development of graphene and its application in photocatalysts based on existing research literature and data. The result shows that, currently, graphene-based nanomaterials for medical applications are a popular research topic. In this paper, the structure, characteristics, synthesis and surface modification of graphene is classified into covalent and non-covalent approaches.
With the continuous development, the demand for concrete has increased. But the supply of raw materials is insufficient. So, the research should be conducted on new types of concrete. There are new types of concrete with materials such as seawater sea-sand concrete and recycled concrete. This paper summarizes the latest progress about mechanical properties of these two materials and summarizes the results of a large number of scholars on the mechanical properties of seawater sea sand concrete and recycled concrete. Their relevant research is in line with the requirements of carbonaceous peaking and carbon neutral strategy.
Automobile exhaust emissions are the main source of pollution at present, and Three-Way catalytic converter (TWC), as the main mean of automobile exhaust purification, can effectively control the negative impact posed by automobile exhaust. However, there are still some problems that can be improved in the current TWC, such as catalyst sintering and low temperature catalytic efficiency. As an advanced catalytic field, it has a good effect on CO governance in TWC. This paper mainly studies how single-atom catalysis catalyzes CO in TWC based on related literature researches and analyzes the mechanisms and experimental data from other teams. The preparation method of SAC will also be introduced. It is concluded that SAC has a good effect on CO catalysis in TWC, and it can also improve the existing problems in TWC. Different supports also have different mechanisms for CO oxidation. In the future, if SAC can be applied in TWC, all aspects will be significantly improved.
In recent years, Fiber Reinforced Polymer(FRP) has been widely used as a reinforcement material to improve the flexural capacity of beams and slabs, and FRP has good corrosion resistance. And because of the wide variety of fiber materials, so more than the role of ordinary steel.This paper will discuss whether it can replace steel to improve building durability in alkaline environment such as seawater sea sand concrete.Due to the lack of natural river sand and water resources, people have been trying to use sea sand seawater instead in recent years. But there are many safety accidents because of the corrosion of steel bars. Due to the good corrosion resistance of FRP, this paper discusses the feasibility of its service as a steel bar in marine sand concrete, including its failure characteristics after corrosion and the problems and improvement strategies when working with Seawater-Sea Sand Concrete(SWSSC). The research object of this paper is Glass Fiber Reinforced Polymer(GFRP) steel bar and Carbon Fiber Reinforced Polymer(CFRP) steel bar. Glass fiber and carbon fiber are widely used materials in current production activities, mostly in the field of mechanical manufacturing. Although engineering materials have been used in recent years, the time is short. In this paper, it is discussed that in the simulated pore solution of concrete stirred by seawater and sea sand and exposed in the environment of seawater immersion, by increasing the temperature to accelerate the reaction rate, it is found that the corrosion resistance of the two kinds of steel bars is very different, but the corrosion mechanism is similar, both of them are caused by the dissolution of the resin matrix. The fiber is bare, and the internal fiber actually has the bearing capacity, but the ability of the material to bear the force is still reduced due to the loss of the bonding of the resin matrix. Therefore, this paper proposes that it is possible to find a more corrosion-resistant resin matrix or add a layer of medium at the interface between the fiber and the matrix to maximize the role of the fiber.