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Verified CAS / Academic Author2 Decoded Studies

Prof. Yu-Fen Wang

College of Chemistry, Nankai University

Research Publications & English Decoded Briefs

Showing 2 publications
SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3588-2

In-situ polymer-derived SiOCnws-Cf/SiC(rGO) composites: a potential candidate for EMI shielding and thermal management

The rapid evolution of aerospace technology necessitates the development of multi-functional composites that combine light weight, mechanical robustness, thermal protection/insulation, and electromagnetic interference (EMI) shielding. C/SiC porous ceramic composites are promising for thermal protection in hypersonic vehicles. Here, we report a facile strategy to fabricate Cf/SiC composite polymer-derived ceramics (PDCs) via re-pyrolysis of high-energy ball-milled polycarbosilane-vinyltriethoxysilane-graphene oxide (PVG) with Cf/SiC(rGO)p blend interleaves. In-situ generated honeycomb-like cellular structures and non-directional channels reduce density and increase porosity. High-quality SiO2 joints, formed from Si-dangling bonds, strengthen interfacial bonding via a brazing effect, while in-situ SiOC nanowires (SiOCnws) create a hierarchically enhanced network, improving fracture toughness and crack resistance. Multi-scale interfacial/dipole polarization enhances EMI shielding. The optimized Cf(0.2)/SiC(rGO) composite exhibits low density (1.49 g cm−3), high fracture toughness (6.32 MPa m1/2), hardness (7.18 GPa), compressive strength (72.67 MPa), and EMI shielding effectiveness of 58.31 dB. It maintains structural stability under butane blowtorch ablation at ~1300 °C for 3600 s. Porous variants show thermal conductivity of 0.211 W m−1 K−1 with 69.74% porosity. These multi-functional composites are promising for thermal protection systems in aerospace applications.

SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3995-6

Pore-Engineering of Single-Site Ti(IV) Embedded Zr-MOFs for Enhanced Catalytic Hydroboration of Large-Size Carbonyl Substrates

The deployment of single-site metal catalytic nodes into zirconium-based metal-organic frameworks (Zr-MOFs) offers vast advantages in catalytic recyclability, product separation, and mechanistic analysis, underscoring their paramount significance in heterogeneous catalysis. Nonetheless, their occupation within pores/channels usually diminishes mass transfer and catalytic efficiency during reactions such as the hydroboration of carbonyl compounds, especially for bulkier substrates. To address this issue, three microporous single-site Ti(IV) embedded Zr-MOFs with sequentially extended ligand arms are novelly synthesized to enable precise pore modulation ranging from 9.04, 10.12, to 11.18 Å. The catalytic performance is investigated using eight carbonyl compounds of varying sizes and four additional larger-scale substrates, which demonstrates that the catalytic efficiency is increased through pore size regulation, yet still away from optimal catalytic performance. Then a further strategy was shifted to the linker installation of linear dicarboxylate ligands chelated single-site Ti(IV) within coordination-unsaturated windows of mesoporous Zr-MOFs, and the result elucidates that the obtained catalyst exhibits superior catalytic efficiency (all exceeding 90%) while preserving the inherent mesoporosity of Zr-MOFs with a pore size of approximately 21.73 Å. We believe this research provides critical guidance for future research on structural design and catalytic optimization of MOFs, opening new avenues in heterogeneous catalysis.