ACS Appl Mater Interfaces
August 2023
Carbon contamination from graphite molds during spark plasma sintering (SPS) considerably affects the properties of the sintered materials, especially transparent ceramics. Herein, transparent YAlO (YAG) ceramics were prepared via SPS using Mo and Ta foils, separately and in tandem, as protective barriers against carbon contamination. The effects of Ta and Mo foils on the transparency and microstructure of the ceramics, and their protection mechanisms were studied.
View Article and Find Full Text PDFThe synthesis of methanol and dimethyl ether (DME) from carbon dioxide (CO) and green hydrogen (H) offers a sustainable pathway to convert CO emissions into value-added products. This heterogeneous catalytic reaction often uses copper (Cu) catalysts due to their low cost compared with their noble metal analogs. Nevertheless, improving the activity and selectivity of these Cu catalysts for these products is highly desirable.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2022
Optically transparent ceramics and MgO in particular are promising materials for a wide range of optical applications. This study introduces exceptionally highly transparent MgO ceramics produced via spark plasma sintering (SPS) at relatively low temperature and pressure by optimal incorporation of LiF as a sintering additive. The effect of LiF content on the microstructural and optical properties is presented with emphasis on its function as a densification aid and an agent for minimizing residual carbon contamination.
View Article and Find Full Text PDFWe developed synthetic methods for the doping of metals (M) with metallic nanoparticles (NPs). To the best of our knowledge - unlike oxides, polymers and carbon-based supports - metals were not used so far as supporting matrices for metallic NPs. The composites (denoted M1-NPs@M2) comprise two separate phases: the metallic NPs (the dopant) and the entrapping 3D porous metallic matrix, within which the NPs are intimately held and well dispersed.
View Article and Find Full Text PDFAnion-conducting ionomer-based nanofibers mats are prepared by electrospinning (ES) technique. Depending on the relative humidity (RH) during the ES process (RH), ionomer nanofibers with different morphologies are obtained. The effect of relative humidity on the ionomer nanofibers morphology, ionic conductivity, and water uptake (WU) is studied.
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