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As devices become more miniaturized and integrated, the heat flux density has increased, highlighting the issue of heat concentration, especially for low thermal conductivity gallium oxide (Ga2O3). This study utilizes diamond composite substrates with an AlN transition layer to assist Ga2O3 in rapid thermal dissipation. All samples were prepared using pulsed laser deposition (PLD) and annealed at 600–1000 °C. The microstructure, surface morphology, vacancy defects, and thermal characteristics of post-annealed Ga2O3 were then thoroughly investigated to determine the mechanism by which annealing temperature influences the heat transfer of heterostructures. The results demonstrate that increasing the annealing temperature can improve the crystallinity of Ga2O3 while also reducing oxygen vacancy defects from 20.6% to 9.9%. As the temperature rises to 1000 °C, the thermal conductivity of Ga2O3 reaches a maximum of 12.25 W/(m·K). However, the interface microstructure has no direct correlation with annealing temperature. At 700 °C, Ga2O3/diamond exhibits a maximum thermal boundary conductance of 127.06 MW/(m2·K). Higher temperatures (>800 °C) cause irregular mixtures to form near the heterointerface, intensifying phonon interface scattering and sharply deteriorating interfacial heat transfer. These findings contribute to a better understanding of the heterointerface thermal transfer influence mechanism and provide theoretical guidance for the thermal management design and physical analysis of Ga2O3-based power devices. [ABSTRACT FROM AUTHOR]

Sulfamethoxazole is a widely—used antibiotic with high water solubility and low biodegradability, which was considered a refractory environmental pollutant. Hence, a series of functionalized hybrids uniting Cu3P with TiN were prepared. The Cu3P/TiN—x composites remarkably removed the sulfamethoxazole in solution compared with Cu3P and TiN alone. All the as—prepared Cu3P/TiN—x hybrids integrated the advantages of strong adsorption and photocatalysis and achieved removal rates above 70% of sulfamethoxazole. Among the composites, the Cu3P/TiN—2 with a 1:1 molar ratio of Cu: Ti reached a 90% removal rate under dark adsorption for 30 min and subsequent photodegradation for 120 min. The enhanced performance of the Cu3P/TiN—x composites is attributed to the introduced flocculent TiN with a large specific surface area and high conductivity that provide more reactive sites and high electron transferability. Meanwhile, the strong corrosion resistance and chemical stability were also beneficial to the improved performance. Cycling experiments further demonstrate the stability and reliability of the composites. In addition, the capture experiments indicated that the superoxide radical (·O2−) and hydroxyl radical (·OH) played a major role in sulfamethoxazole degradation. [ABSTRACT FROM AUTHOR]

4H‐SiC is widely used in power electronics owing to its superior physical properties. However, temperature‐induced stresses compromise the reliability of 4H‐SiC power devices in high‐temperature applications, warranting precise, and nondestructive stress characterization responsive to temperature variations. Herein, a temperature‐dependent predictive model is proposed for analyzing the Raman shift–stress in 4H‐SiC. The 4H‐SiC epitaxial samples prepared via chemical vapor deposition are characterized using in situ variable‐temperature Raman spectroscopy, resulting in a temperature correction factor of approximately −0.021 cm−1 K−1, which is integrated into the conventional Raman shift–stress relationship to assess stress variations induced by temperature variations. The elastic modulus tensor of 4H‐SiC at various temperatures determined using molecular dynamics simulations indicates a linear reduction in modulus with increasing temperature. This variable temperature modulus is incorporated into the Raman shift–stress relationship. Furthermore, a finite element method is used for model simplification to perform stress calculations in three axial directions. The experimental results confirm the consistency between calculated and experimental values with a 10% error range under the uniaxial stress condition. The study findings provide valuable insights into assessing stress evolution in 4H‐SiC under temperature variations based on Raman spectroscopy, thereby advancing the application of spectroscopic techniques in material stress detection. [ABSTRACT FROM AUTHOR]

Abstract: The CO2 desorption tests were conducted at 363–378 K for 5.0 mol/L blended monoethanolamine (MEA)‐diethanolamine (DEA) solutions to develop the energy efficient solvents with high CO2 production and low energy consumptions. These desorption tests were performed with a recirculation process for various preloaded, 5 mol/L (4.5 + 0.5 to 0.5 + 4.5) MEA‐DEA solutions to find out the optimized solvents with minimum heat duty. Therefore, 1–4 mol/L and 0.5–0.45 mol/L MEA‐DEA solvents have larger CO2 production (nCO2) and lower heat duties ( H CO 2) than 5 mol/L DEA under similar operation conditions. They have lower heat duty (510 and 538 kJ/mol) than DEA (572 kJ/mol) due to increased CO2 desorption rates, despite 10% higher heat input (QTotal) than DEA. Moreover, the critical points were studied as research focus of amine regeneration curves, along with reaction energy calculation. Finally, secondary amines blending minor MEA (<20%) as promotor turned out to be an alternative approach of solvents improvement with low energy requirement. [ABSTRACT FROM AUTHOR]