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Single atom catalysts (SACs) have been growing as an emerging “hot” topic in environmental remediation. Their performance can be rationally optimized via modulating spatial coordination configuration and porous structure of SACs, which is still challenging. Herein, a novel Si, N co-coordinated cobalt SACs (p-CoSi1N3@D) with 3D freestanding architecture was tailored via employing natural mineral (diatomite) as Si source and porous template. Theoretical calculations and experimental analysis reveal that Si substitution dramatically decreases electronegativity of CoN4 moieties and thus accelerates interaction and electron transfer between peroxymonosulfate and Co single atom center. Moreover, p-CoSi1N3@D inherits hierarchically porous architecture of diatomite, providing more accessible cobalt sites and open diffusion channels for peroxymonosulfate and contaminants in water treatment applications. Thanks to optimal coordination structure and porous architecture, p-CoSi1N3@D can serve as highly active catalyst toward peroxymonosulfate activation, with a turn-over frequency of 299.8 min− 1 for bisphenol A degradation, surpassing those of catalysts with transition metal SACs or oxides in disclosed literature. This work provides a novel vision for development of SACs towards wastewater reclamation.

The wound healing process is divided into four phases of hemostasis, inflammation, proliferation, and remodeling that each wound needs to go through to heal normally. Each phase is crucial to the healing of the wound. Herein, for the first time, we describe an emerging bifunctional hybrid fiber membrane of ZnO–Fe2O3/kaolinite nanoclay/poly-(3-caprolactone)-gelatin (ZnO–Fe2O3/Kaol/PG) that concurrently controls bleeding, prevents bacterial colonization, reduces excessive inflammation, and facilitates wound healing for the early emergency self-rescue. Topical treatment with the fiber membrane in bacteria-infected mice models could accelerate wound healing through reducing bacterial growth, and promote cell proliferation and neovascularization, which is attributed to the antibacterial and anti-inflammatory activity of ZnO–Fe2O3/Kaol. Kaolin can activate the intrinsic coagulation cascade, in addition, it can concentrate on blood platelets, RBCs, and clotting factors by absorbing fluid. Fe2O3 can facilitate RBC aggregation and clotting, while ZnO can mediate the inhibition of the release of pro-inflammatory cytokines and antibacterial effect. The fibrous architecture of PG electrostatically spun fibers can provide an appropriate environment for wound healing. Here, for the first time, we found that ZnO–Fe2O3/Kaol can control bleeding quickly for wound injury and protect the wound from external bacterial infection and reduces inflammation. The versatility and portability of the as-prepared hybrid fiber membrane make it an effective strategy for hemorrhage control and wound healing.

The effect of oxygen vacancy on the optical properties of porous zirconia(ZrO2) was discussed based on the preparation and optical characterization of this material.The configuration coordinate diagram for a discussion of the optical performances of the ZrO2 system was carefully amended.The samples used in the experiments were prepared by the hydrothermal method.The product possesses a porous structure constructed by amorphous zirconia particles and the specific surface area of the product was 151.9 m2·g-1.Deconvolution was used to analyze the photoluminescence(PL) spectra and the results are different in some aspects compared with previous reports.The main PL bands of the as-prepared product were located in the violet to blue region while those of the samples after treatment by H3PO4 red-shifted to the blue-green region.Neither the porous structure nor the existence of phosphor reagents in ZrO2 induced any new PL peaks.The oxygen vacancies in the samples formed a new energy level that trapped electrons to form a color center and then luminescent emissions were induced.

Diaspore (α-AlOOH) was heated at various temperatures from 300 to 1 000 °C for 2 h. The alteration of diaspore by thermal treatment was investigated by differential thermal analysis, thermogravimetric analysis and X-ray diffraction. The mechanism of thermal decomposition of diaspore was discussed according to the Coats-Redfern equation. It is found that after thermal treatment at 500 °C, diaspore is transformed entirely to corundum (α-Al2O3). Combined with the mass loss ratio obtained from the thermogravimetric analysis data, the activation energies for the thermal treatment of diaspore are calculated as Ea=10.4 kJ/mol below 400 °C and Eb=47.5 kJ/mol above 400 °C, respectively, which is directly related to the structural alteration of diaspore during the thermal treatment. The results indicate that the thermal decomposition of diaspore is conducted primarily by means of an interfacial reaction.