The photocatalytic efficiency of hematite (α-Fe 2 O 3 ) is limited by its photoexcited state lifetime and diffusion length. By adjusting the surface structure, the photogenerated electron pairs can migrate to the surface and the charge recombination can be suppressed, which can effectively solve these problems and improve the photo-Fenton performance. In this study, four kinds different morphologies of α-Fe 2 O 3 - x (truncated hexagonal bipyramidal, cubic, hexagonal shape, and spherical) were synthesized by hydrothermal method , and a photocatalyst (H-α-Fe 2 O 3 - x ) with higher catalytic activity was prepared by hydrogenation. The results of UV–Vis DRS , PL , Raman, and XPS analysis , the oxygen vacancies and Fe (II) species were introduced into the α-Fe 2 O 3 catalyst after the hydrogenation reaction. The H-α-Fe 2 O 3 - x showed good degradation performance for TC and DX as EMPs model pollutants. The results show that the formation of oxygen vacancy and Fe 2+ is the main factor to improve the photocatalytic activity of the reaction system. Furthermore, the reaction mechanism revealed that reactive radicals involved in the H-α-Fe 2 O 3 - x photocatalytic system were •OH, •O 2 − , and h + responsible. This study provides an alternative technology for an easy and effective means for bandgap engineering to improve the photocatalytic performance of photocatalysts and facilitate widening environmental application.
Wen Liu,Xiao Yang,Pengpeng Li,Feng Sang,Lina Cao,Bingxu Zhang,Zhizhen Meng,Zhaipu Ma,Changcan Shi
Uncontrollable hemorrhage, especially uncompressible and massive hemorrhage, is life threatening. To develop a kind of hemostatic material that is biocompatible and has effective hemostatic performance, a starch-polyethylene glycol sponge (St-PEG sponge) incorporated with electrospraying microspheres made from carboxymethyl chitosan and sodium alginate (CMC/SA eMPs) is employed to fabricate the topical hemostatic agent for application. To load thrombin safely and effectively, CMC/SA eMPs encapsulating thrombin compounds (eMPs@Thr) are further incorporated with St-PEG sponge to obtain eMPs@Thr/sponge. The results show that eMPs@Thr/sponge could obviously reduce blood loss and shorten the hemostatis time compared with commercial hemostatic products Kuai Kang. The construction of the eMPs@Thr/sponge could not only maintain the expandable properties of the St-PEG sponge but also strengthen the procoagulant activity. Therefore, this work provides a facile approach for loading thrombin given the fact that thrombin suffers from instability and risk of thrombus. It is predicted that eMPs@Thr/sponge might hold great potential in uncompressible and massive hemorrhage control.
危险品化学品经营许可证（带存储）