TiNiSn-based half-Heusler semiconducting compounds have the highest potential as -type thermoelectric materials for the use at elevated temperatures. In order to use these compounds in a thermoelectric module, it is crucial to examine their behaviour at a working temperature (approximately 1000 K) under oxygen and a humid atmosphere. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were utilized to study the surface composition and oxidation of the TiNiSn alloy at elevated temperatures. It was found that during heating in vacuum, Sn segregates to the surface. Exposing the alloy to oxygen at room temperature will cause surface oxidation of Ti to TiO₂ and Ti₂O₃ and some minor oxidation of Sn. Oxidation at 1000 K induces Ti segregation to the surface, creating a titanium oxide layer composed of mainly TiO₂ as well as Ti₂O₃ and TiO. Water vapor was found to be a weaker oxidative gas medium compared to oxygen.
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http://dx.doi.org/10.3390/ma11112296 | DOI Listing |
Langmuir
January 2025
Key Laboratory of Thorium Energy, Chinese Academy of Science Shanghai Institute of Applied Physics, Shanghai 201800, China.
Hydrogen evolution from water, catalyzed by solar energy, is a promising yet challenging endeavor. Small-sized catalysts usually exhibit high utilization and high performance in the hydrogen evolution field. However, the high surface energy tends to make them aggregate.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Electrical Engineering, Feng Chia University, Taichung, 407802, Taiwan.
This study presents an innovative glucose detection platform, featuring a highly sensitive, non-enzymatic glucose sensor. The sensor integrates nickel nanowires and a graphene thin film deposited on the gate region of an extended-gate electric double-layer field-effect transistor (EGEDL-FET). This unique combination of materials and device structure enables superior glucose sensing performance.
View Article and Find Full Text PDFHeliyon
January 2025
Nuclear Chemistry Division, Department of Chemistry, Atomic Energy Commission, P. O. Box: 9061, Damascus, Syrian Arab Republic.
Molecular scale information is needed to understand ions coordination to mineral surfaces and consequently to accelerate the design of improved adsorbents. The present work reports on the use of two-dimensional correlation Fourier Transform infra-red spectroscopy (2D-COS-FTIR) and hetero 2D-COS-FTIR- X-ray diffraction (XRD) to probe the mechanism of Cr(VI) removal from aqueous solutions by activated carbon (AC) and its composite with PWO (AC-composite). The adsorption data at an initial Cr(VI) concentration of 320 mg L (320 ppm) revealed maximum adsorption capacities of 65 mg g for AC and 73 mg g for AC-composite, corresponding to removal percentages of 83 % and 94 %, respectively.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Biopharmacy, School of Pharmaceutical Sciences, Jilin University, Changchun, People's Republic of China.
Purpose: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Oxaliplatin (OXA) is currently the primary chemotherapeutic agent for CRC, but its efficacy is limited by the tumor microenvironment (TME). Here, we present a combined approach of chemotherapy and TME modulation for CRC treatment.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
January 2025
Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany.
Since water is both a product and a common reactant impurity in the (partial) methanol oxidation to methyl formate (MeFo) on gold, its effect on the isothermal selectivity to methyl formate was investigated under well-defined single-collision conditions employing pulsed molecular beam experiments and in situ IRAS measurements. Both a flat Au(111) and a stepped Au(332) surface were used as model catalysts to elucidate how water affects the reactivity of low-coordinated step sites as compared to (111) terrace sites employing a range of reaction conditions. The interactions of water with methanol/methoxy as well as with oxygen species are addressed.
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