Glass fiber/polyimide aerogel composites are prepared by adding glass fiber mat to a polyimide sol derived from diamine, 4,4′‐oxydianiline, p‐phenylene diamine, and dianhydride, 3,3′,4,4′‐biphenyltetracarboxylic dianhydride. The fiber felt acts as a skeleton for support and shaping, reduces aerogel shrinkage during the preparation process, and improves the mechanical strength and thermal stability of the composite materials. These composites possess a mesoporous structure with densities as low as 0.143–0.177 g cm−3, with the glass fiber functioning to improve the overall mechanical properties of the polyimide aerogel, which results in its Young's modulus increasing from 42.7 to 113.5 MPa. These composites are found to retain their structure after heating at 500 °C, in contrast to pure aerogels which decompose into shrunken ball‐like structures. These composites maintain their thermal stability in air and N2 atmospheres, exhibiting a low thermal conductivity range of 0.023 to 0.029 W m−1 K−1 at room temperature and 0.057to 0.082 W m−1 K−1 at 500 °C. The high mechanical strengths, excellent thermal stabilities, and low thermal conductivities of these aerogel composites should ensure that they are potentially useful materials for insulation applications at high temperature.

The activation of O 2 into the dioxide radical (O 2 •− ) at room temperature serves as a critical chemical process implicated in environmental remediation and industrial chemical processes, but the involved mechanism remains unclear. Herein, we address this challenge by the radical detection method combined with DFT study and unveil that the O 2 activation reaction could take place merely in porous carbons (PCs) at room temperature. DFT calculations indicate that sp 2 -conjugated carbons can transfer a π* electron to the outer orbit of the O 2 molecule derived by the space confinement in ultramicropores (∼0.4 nm), and the presence of edge site defects and heterogeneous atoms can facilitate the electron transfer due to increased quantity of free electrons. The produced O 2•− radicals could be further trapped and enriched on the surface of MgO as predicted by DFT calculations, which is subsequently confirmed by radical detection analysis of the designed MgO-loaded PCs. Furthermore, the O 2 activation and O 2•− enrichment on MgO-loaded PCs are applied in a probe reaction of room-temperature catalytic H 2 S oxidation, in which an outstanding catalytic performance is achieved. These findings provide valuable insight into the intrinsic origin of the O 2 activation at room temperature and open a fresh route to efficient formation and concentration of O 2•− for aerobic oxidization processes.

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