Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(25)60623-2
Oxidative coupling of methane (OCM) is a promising route for direct conversion of methane to C2–C3 hydrocarbons, but conventional thermal catalysis suffers from insufficient conversion and selectivity. Here, we report a novel Mn2O3-TiO2-Na2WO4/SiO2+SiC microwave catalyst prepared by ball-milling, which enables efficient OCM under microwave irradiation. At 700 °C, the microwave catalytic reaction mode (MCRM) achieves a CH4 conversion of 26.6%, a C2–C3 selectivity of 76.5%, and a C2–C3 yield of 20.4%, significantly outperforming the conventional reaction mode (CRM) under identical conditions (12.3%, 61.9%, and 7.5%, respectively). The catalyst exhibits stable performance for 20 h in MCRM, maintaining CH4 conversion above 25% and C2–C3 selectivity above 76%. Characterization (XRD, XPS, O2-TPD, Raman) reveals that calcination promotes Mn–Ti interaction, increasing peroxy species and lattice oxygen (Oγ), which enhance reactivity and selectivity. Notably, microwave irradiation reduces the apparent activation energy from 173 kJ/mol (CRM) to 27.5 kJ/mol, facilitating free radical coupling and suppressing deep oxidation. These findings provide a low-temperature, energy-efficient strategy for methane valorization, contributing to sustainable chemical manufacturing.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3724-y
Respiratory sensors capable of real-time monitoring are essential for health management, disease prevention, and early diagnosis. Achieving real-time respiratory monitoring requires sensors with fast and sensitive response, high stability, and mechanical flexibility. Here, we demonstrate an amino-modified graphdiyne (NH2-GDY)-based sensor for real-time monitoring of human respiratory status. Compared to pristine graphdiyne, the amino-functionalized NH2-GDY exhibits enhanced adsorption capacity for water molecules. Its enlarged nanoporous structure facilitates the migration of water molecules, enabling rapid adsorption/desorption. The sensor demonstrates ultra-fast and ultra-sensitive respiratory responses, coupled with remarkable flexibility and stability. When integrated into a wearable electronic system, it achieves real-time monitoring of sleep apnea syndrome (SAS). This work highlights the feasibility of novel carbon-based respiratory sensors in advanced health monitoring applications. The sensor was fabricated on polyimide (PI) substrates, ensuring mechanical robustness. The amine-rich structure and nanoscale porosity of NH2-GDY facilitate rapid adsorption and transfer of water molecules, enabling fast and highly sensitive respiratory responses. This strategy provides a pivotal solution for early SAS diagnosis and disease management, establishing a novel respiratory sensing paradigm while expanding the application landscape of graphdiyne-based materials.