Materials with high thermal conductivity (κ) are of technological importance and fundamental interest. We grew cubic boron nitride (cBN) crystals with controlled abundance of boron isotopes and measured κ greater than 1600 watts per meter-kelvin at room temperature in samples with enriched B or B. In comparison, we found that the isotope enhancement of κ is considerably lower for boron phosphide and boron arsenide as the identical isotopic mass disorder becomes increasingly invisible to phonons. The ultrahigh κ in conjunction with its wide bandgap (6.2 electron volts) makes cBN a promising material for microelectronics thermal management, high-power electronics, and optoelectronics applications.
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http://dx.doi.org/10.1126/science.aaz6149 | DOI Listing |
J Mol Model
January 2025
Escuela Superior de Física y Matemáticas, IPN S/N, Edificio 9 de la Unidad Profesional "Adolfo López Mateos", Col. Lindavista, Alc. Gustavo A. Madero, 07738, Mexico City, Mexico.
Context: "Nanostructure of graphene-reinforced with polymethyl methacrylate" (PMMA-G), and vice versa, is investigated using its molecular structure, in the present work. The PMMA-G nanostructure was constructed by bonding PMMA with graphene nanosheet in a sense to get three different configurations. Each configuration consisted of polymeric structures with three degrees of polymerization (such as monomers, dimers, and trimers polymers, respectively).
View Article and Find Full Text PDFLangmuir
January 2025
School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.
Aerogels hold great potential in thermal insulation, catalytic supports, adsorption, and separation, due to their low density, high porosity, and low thermal conductivity. However, their inherent mechanical fragility and limited control functionality pose substantial challenges that hinder their practical use. In this study, a strategy is developed for the fabrication of cross-linked aramid nanofiber aerogels (cANFAs) by combining internanofiber surface cross-linking with ice-templating techniques.
View Article and Find Full Text PDFLangmuir
January 2025
College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin 150040, China.
Solar-driven interfacial evaporation technology is regarded as a promising strategy for global freshwater shortage owing to its green and sustainable desalination process. Graphene aerogel (GA) is widely utilized in the design of solar-driven steam generation systems due to its excellent photothermal conversion efficiency and broad spectral absorption. Given the significant impact of hydrophilicity and thermal insulation on the performance of evaporators, nitrogen doping in the graphene structure not only effectively enhances its wettability but also allows for moderate tuning of its thermal conductivity, thereby optimizing the overall performance of the evaporator.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Integrated Circuits and Electronics, Beijing Institute of Technology, Beijing 100081, P. R. China.
Efficient thermal generation from solar/electric energy in transparent films remains challenging due to the limited toolbox of high-performance thermal generation materials and methods for microstructure engineering. Here, we proposed a two-step strategy to introduce hierarchical wrinkles to the MXene composite films with high transparency, leading to upgraded photo/electrothermal conversion efficiency. Specifically, the thin film contains protic acid-treated MXene layers assembled with Ag nanowires (H-MXene/Ag NWs).
View Article and Find Full Text PDFSci Rep
January 2025
Sustainability Solutions Research Lab, Faculty of Engineering, University of Pannonia, Egyetem Str. 10, Veszprém H, 8200, Veszprém, Hungary.
This study endeavors to tackle the energy requirements of the building sector by employing passive design strategies. However, there exists a dearth of comprehension regarding the energy efficiency performance of foamed alkali-activated materials. To bridge this research gap, the study proposes a solution in the form of a thermally proficient wall material crafted from ceramic tile dust (CTD), class C fly ash (FA), and Ground Granulated Blast-Furnace Slag (GGBS), all of which are industrial by-products.
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