![]() Therefore, they have been extensively used in separation and purification technologies as efficient adsorbents. Nanoporous carbon materials from biomass exhibit a high surface area due to well-defined pore structures. This work paves a way to design a membrane with photocatalytic performance by constructing the interface heterostructure. O2 -) play a dominant role in the reaction of photodegradation supported by a free radical-trapping experiment. ![]() The abundant O2 adsorbed on the porous SiO2 aerogel surface acts as an electron (e-)-trapping agent, which can also decrease the work function of the composite materials. ![]() The mechanism study indicates that the separated photogenerated carriers diffuse to the composite membrane surface rapidly on the three-phase interface of P-S-T/C. Moreover, P-S-T/C exhibits excellent stability and recyclability under simulated sunlight. On combining with the capillary condensation of a bilayer structure, P-S-T/C exhibits excellent removal capability for anionic and cationic dyes. Its photocatalytic performance is validated by photodegradation of organic dyes in a low-oxygen (O2) water environment. The three-phase interface heterostructure was formed by TiO2, conductive CFC, and the SiO2 aerogel. Activated poly(vinylidene fluoride) (PVDF) with titanium dioxide (TiO2) and a silicon dioxide (SiO2) aerogel are electrospun as the top layer. A polydopamine (PDA)-modified conductive carbon fiber cloth (CFC) is used as the substrate. Needle-like zinc oxide obtained by carbothermic reduction has high purity and can replace zinc oxide produced by an indirect process.Ī multicomponent composite membrane (P-S-T/C) with three-phase interface heterostructure is ingeniously designed. Under the best reduction process, the purity of zinc oxide product is 99.5%, and the recovery of zinc is more than 99.25%. The best process conditions for zinc oxide production by carbothermic reduction are as follows: reduction temperature of 1250 ☌, reduction time of 60 min, and reduction agent addition of 22 wt.%. Under the modified conditions, the chloride content in the roasted zinc ash is reduced to 0.021 wt.%, and the dechlorination rate is more than 99.5%, which can meet the requirements of zinc oxide production. The results of a chloride ion removal test show that the optimal roasting temperature is 1000 ☌, with a holding time of 60 min. Basic zinc chloride can be roasted and decomposed to reduce the chlorine content in zinc ash. Zn in zinc ash is mainly presented in the form of zinc oxide (ZnO), basic zinc chloride (Zn5(OH)8Cl2H2O), and metallic zinc (Zn). ![]() This process includes two steps: high-temperature roasting of zinc ash for dechlorination and a carbothermal reduction of dechlorination ash. A new technology for zinc oxide production, by a carbothermal reduction of zinc ash, is proposed. In this work, in order to reduce the energy consumption of the direct reduction process and improve the resource-recovery rate. Zinc ash is a by-product of the hot-dip galvanizing process and the electrolytic zinc process, which is classified as a hazardous waste consisting predominately of zinc oxide that could be recovered as the useful main resource for ZnO preparation. This biogenic method offers a facile approach to nanoparticles for biological purposes, and the strategy may be extended to other metal oxide and their composites with metallic silver nanoparticles as a more effective approach compared to the physical and chemical routes. The results demonstrated that the modification of ZnO with silver nanoparticles enhanced the antibacterial potency but reduced the antioxidant activity. The biological activity of the nanoparticles was studied for their antibacterial and antioxidant capacity so as to assess their ability to hinder bacterial growth and capture radical species respectively. The analysis from the TEM image showed the particles were of spherical morphology with a mean size of 35 nm (ZnO) and 33.50 nm (Ag/ZnO). The absorption spectrum of the nanocomposite indicated a red shifting of the absorption band of the metallic ZnO and a surface plasmon resonance (SPR) band's appearance in the visible region due to the metallic Ag nanoparticles. The powder X-ray diffraction confirmed hexagonal phase ZnO, while the Ag/ZnO nanocomposites identified additional planes due to cubic phase Ag nanoparticles. Their elemental composition was studied using EDX analysis, while elementary mapping was used to show the distribution of the constituent elements. The nanomaterials were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectrophotometer (FTIR), ultraviolet-visible spectrophotometer, scanning, and transmission electron microscopy (SEM and TEM). Zinc oxide (ZnO) and silver-zinc oxide (Ag/ZnO) nanocomposite were synthesized by a green method using Zn(CH 3 COO) 2 and AgNO 3 as precursors for zinc and silver respectively and Urginea epigea bulb extract as a reducing/capping agent.
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