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In modern society where fossil fuel prices are increasing and environmental issues are becoming more severe, biodiesel, as a new type of clean fuel, is receiving increasing attention. Biodiesel has the advantages of renewability, environmental friendliness, and good fuel properties, demonstrating broad application prospects. However, the use of biodiesel also faces some challenges, such as higher density and kinematic viscosity, lower calorific value, etc. The application of nanoparticles in biodiesel engines helps to achieve the goal of clean fuel. In terms of fuel characteristics, nanoparticles increase the calorific value, cetane value, and flash point of the fuel, improving combustion efficiency and safety, but increasing density may affect combustion. The use of nanoparticles can promote micro explosions and secondary atomization of fuel, improve combustion characteristics, and increase cylinder pressure, heat release rate, and brake thermal efficiency while reducing fuel consumption. Nanoparticles reduce HC and CO emissions, improve combustion through higher oxygen and reaction area, and reduce incomplete combustion products. On the contrary, nanoparticles also increase CO2 emissions because better combustion conditions promote oxidation reactions. For NOX emissions, some nanoparticles lower the combustion temperature to reduce emissions, while others increase emissions. Comparison shows that all nanoparticles offer varying degrees of improvement in engine performance and emissions, but the improvement provided by TiO2 nanoparticles is significantly better than that of other nanoparticles. In the future, the synergistic effect of multiple nanoparticles should be explored to further improve performance and reduce emissions, achieving effects that cannot be achieved by a single nanoparticle. [ABSTRACT FROM AUTHOR]

Proton‐conducting solid oxide cells (P‐SOCs) as energy conversion devices for power generation and hydrogen production have attracted increasing attention recently. The lack of efficient proton‐conducting air electrodes is a huge obstacle to developing high‐performance P‐SOCs. The currently widely used air electrode material is Co/Fe based perovskite oxide, however, there is still no systematic research on studying and comparing the roles of diversiform elements at the B site for Co/Fe based perovskite oxide. Here, a machine learning (ML) model with eXtreme Gradient Boosting (XGBoost) algorithm is built to quickly and accurately predict the proton absorption amount of Co/Fe based perovskite oxides with 27 elements dopant at B site. Hereafter, La(Co0.9Ni0.1)O3 (LCN91) is screened by a combination of the ML model and the density functional theory calculation. Finally, LCN91 is applied to the air electrode of P‐SOC, and the cell exhibits excellent electrochemical performances in fuel cell and electrolysis modes. The current study not only provides a useful model for screening air electrodes of P‐SOC, but also extends the application of ML in exploring the key materials for P‐SOCs and other fuel cells/electrolyzers. [ABSTRACT FROM AUTHOR]

2D semiconducting transition metal dichalcogenides (TMDs) are emerging as promising candidates in the pursuit of advancing semiconductor technology. One major challenge for integrating 2D TMD materials into practical applications is developing an epitaxial technique with robust reproducibility for single‐oriented growth and thus single‐crystal growth. Here, the growth of single‐orientated MoS2 on c‐plane sapphire with atomically thin Fe2O3 decoration layers under various growth conditions is demonstrated. The statistical data highlight robust reproducibility, achieving a single orientation ratio of up to 99%. Density functional theory calculations suggest that MoS2 favors a 0° alignment ([112¯0]//[112¯0]$[ {11\bar{2}0} ]//\ [ {11\bar{2}0} ]$) on the Fe2O3 (0001) surface. This preference ensures single‐oriented growth, even on mirror‐reflected exposed surfaces which typically lead to antiparallel domains. Subsequent optical and electrical analyses confirm the uniformity and undoped nature of MoS2 on Fe2O3‐decorated sapphire, showing its quality is comparable to MoS2 grown on bared sapphires. The results underscore the potential of Fe2O3‐decorated sapphire as an effective substrate for the consistent and high‐quality epitaxial growth of 2D TMDs, illuminating the pathway to epitaxial control of 2D TMD orientation through strategic modulation of crystalline atomic surfaces. [ABSTRACT FROM AUTHOR]

Protonic solid oxide electrolysis cells (P‐SOECs) operating at intermediate temperatures, which have low costs, low environmental impact, and high theoretical electrolysis efficiency, are considered promising next‐generation energy conversion devices for green hydrogen production. However, the developments and applications of P‐SOECs are restricted by numerous material‐ and interface‐related issues, including carrier mismatch between the anode and electrolyte, current leakage in the electrolyte, poor interfacial contact, and chemical stability. Over the past few decades, considerable attempts have been made to address these issues by improving the properties of P‐SOECs. This review comprehensively explores the recent advances in the mechanisms governing steam electrolysis in P‐SOECs, optimization strategies, specially designed components, electrochemical performance, and durability. In particular, given that the lack of suitable anode materials has significantly impeded P‐SOEC development, the relationships between the transferred carriers and the cell performance, reaction models, and surface decoration approaches are meticulously probed. Finally, the challenges hindering P‐SOEC development are discussed and recommendations for future research directions, including theoretical calculations and simulations, structural modification approaches, and large‐scale single‐cell fabrication, are proposed to stimulate research on P‐SOECs and thereby realize efficient electricity‐to‐hydrogen conversion. [ABSTRACT FROM AUTHOR]

Fossil fuel is a non-renewable fuel, and with the development of modern industry and agriculture, the storage capacity of fossil fuels is constantly decreasing. In this study, a systematic study and analysis were conducted on the combustion characteristics, engine performance, and exhaust emission characteristics of castor biodiesel–diesel blends and pure diesel fuel in different proportions at different speeds of a single-cylinder four-stroke diesel engine under constant load. The castor biodiesel required for the experiment is generated through an ester exchange reaction and mixed with diesel in proportion to produce biodiesel–diesel blends. The experimental results show that as an oxygenated fuel with a higher cetane number, the CO, HC, and smoke emissions of diesel and B80 blend fuel at 1800 rpm were reduced by 16.9%, 31.6%, and 68%, respectively. On the contrary, the NOx and CO2 emissions increased by 17.3% and 34.6% compared to diesel at 1800 rpm. In addition, due to its high viscosity and low calorific value, the brake thermal efficiency and brake-specific fuel consumption of the biodiesel–diesel blends are slightly lower than those of diesel, but the biodiesel–diesel blends exhibit lower exhaust gas temperatures. Comparing B80 and diesel fuel at 1800 rpm, the BSFC of diesel at 1800 rpm is 3.12 kg/W·h, whereas for B80 blended fuel, it increases to 4.2 kg/W·h, and BTE decreases from 25.39% to 21.33%. On the contrary, B60 blended fuel exhibits a lower exhaust emission temperature, displaying 452 °C at 1800 rpm. Based on the experimental results, it can be concluded that castor biodiesel is a very promising clean alternative fuel with low waste emissions and good engine performance. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are the main precursors of pollution from ground ozone (O3) and PM2.5, which cause the deterioration of urban air quality. The emissions of VOCs from industrialized areas are significant and their characteristics are complex, which nowadays contribute significantly to the challenges of investigating the emission inventory. Taking a typical industrialized area in Tianjin as a case study, the anthropogenic VOCs emission inventory for 2020 was established in this study by using the activity data from a large-scale survey and the latest emission factors. The impact of VOCs on the environment was analyzed from the perspective of the combined control of PM2.5 and O3. The results showed that the total emission of VOCs in 2020 was about 1.68 Gg, mainly from industrial processes and mobile sources, which accounted for 38.4% and 36.5% of the total emissions, respectively. The top 10 emitted VOCs were toluene, acetone, ethylbenzene, m/p-xylene, i-pentane, n-hexane, formaldehyde, benzene, ethyl acetate and ethylene. The dominant species of O3 formation potential (OFP) were almost all aromatic hydrocarbons and alkenes, with m/p-xylene contributing the most to the OFP emissions (8.90%). The top 10 secondary organic aerosols formation potential (SOAP) emission species were aromatic hydrocarbons and long-chain alkanes, and the largest emission came from toluene (39.9%). An analysis of an ADMS diffusion model showed that VOCs emitted from traffic-heavy main roads and industrialized central areas had the greatest impact on the air quality in the surrounding areas. The VOCs concentration was higher in winter due to unfavorable meteorological conditions. Our research updated the VOC inventory of industrialized areas and evaluated VOCs species reactivity and their impact on ambient air quality. [ABSTRACT FROM AUTHOR]