Simultaneously integrating heterogeneous interface,element doping,and metal decorating was a promising strategy to promote the visible-light-driven photocatalytic activity.Herein,we demonstrated a facile solvothermal ...Simultaneously integrating heterogeneous interface,element doping,and metal decorating was a promising strategy to promote the visible-light-driven photocatalytic activity.Herein,we demonstrated a facile solvothermal route for Ni-doped BiOBr/Bi^(0) with ZnO 3D hierarchical heterojunction(denoted as Z@B/BiNi).The optimal photocatalysts of Z@B/Bi-Ni sample presented a remarkable catalytic performance of high concentrations of tetracycline solution(40 mg/L)than those of the Z@B/Bi,Z@B,BOB and ZnO photocatalysts toward the visible-light-driven degradation.The enhanced photocatalytic mechanism can be proposed as follows:(ⅰ)3D hierarchical heterojunction provided more active sites and accelerated the separation of charge carriers for photocatalytic TC;(ⅱ)formation of oxygen vacancies on the surface over Z@B/Bi-Ni by in-situ reduction of Bi^(0) and Ni doping could serve as the active sites for oxygen activation to adsorb free O_(2) and generate more superoxide radicals;(ⅲ)SPR effect of Bi metal were beneficial to carrier separation and also act as the active site to trap O_(2) molecules.This work clarified the role of unique morphologies,surface plasmonic resonance(SPR)effect of metal Bi,and Ni doping in Z@B/Bi-Ni,and its photocatalytic reaction mechanism was proposed by a series of experiments,characterization and DFT calculations,arousing a new perspective to design hierarchical heterojunction photocatalysts.展开更多
Electrospun cyclodextrin(CD)-based nanofibers with capabilities to remove pollutants from water have been synthesized and characterized.The high-quality nanofibers presented here were synthesized in two simple steps t...Electrospun cyclodextrin(CD)-based nanofibers with capabilities to remove pollutants from water have been synthesized and characterized.The high-quality nanofibers presented here were synthesized in two simple steps that involved in-situ electrospinning of the nanofibers and all nanocomponents,followed by the reduction of silver(Ag+)and iron(Fe3+)ions to nanoparticles using an environmentally benign process that involved irradiation of the electrospun fibers using a tailor-made UV-equipped furnace at low temperatures.In the previously reported study it was observed that Ag and Fe nanoparticles effectively removed a range of different strains of Gram-negative and Gram-positive bacteria from water.As such,this study focused on improving the thermal and mechanical properties of the nanofibers prepared from polymer blends ofβ-CDs with cellulose acetate(CA)and small additions(2 wt%)of functionalized multiwalled carbon nanotubes(fMWCNTs).The electrospinning parameters were varied to determine the optimum conditions for preparation of uniform nonbeaded nanofibers.Bead-free and uniform nanofibers were obtained at a polymer concentration of 32%at the ratio of 1:1β-CDs:CA,syringe injection flow rate of 0.7 mL h−1,15 cm between the tip of the spinneret and the collector,and a voltage of 16 kV.The addition of f-MWCNTs was found to improve the tensile strength of the nanofibers by twofold,relative to nanofibers with no f-MWCNTs.The thermal degradation of the nanofibers was improved by a magnitude of 50°C.The study has shown that adding small amounts of f-MWCNTs improved the thermal stability and mechanical strength of the CD/CA nanofibers significantly.展开更多
基金financially supported by the National Natural Science Foundation of China(21576211)Tianjin Science and Technology Program(22ZYJDSS00060 and 22YDTPJC00920)+1 种基金the Program for Tianjin Innovative Research Team in Universities(TD13-5031)Tianjin 131 Research Team of Innovative Talents。
基金supported by the National Natural Science Foundation of China(No.21576211)Tianjin Program of Science and Technology(No.21ZYJDJC00100)+1 种基金Tianjin Innovative Research Team in Universities(No.TD13-5031)Tianjin 131 Research Team of Innovative Talents。
文摘Simultaneously integrating heterogeneous interface,element doping,and metal decorating was a promising strategy to promote the visible-light-driven photocatalytic activity.Herein,we demonstrated a facile solvothermal route for Ni-doped BiOBr/Bi^(0) with ZnO 3D hierarchical heterojunction(denoted as Z@B/BiNi).The optimal photocatalysts of Z@B/Bi-Ni sample presented a remarkable catalytic performance of high concentrations of tetracycline solution(40 mg/L)than those of the Z@B/Bi,Z@B,BOB and ZnO photocatalysts toward the visible-light-driven degradation.The enhanced photocatalytic mechanism can be proposed as follows:(ⅰ)3D hierarchical heterojunction provided more active sites and accelerated the separation of charge carriers for photocatalytic TC;(ⅱ)formation of oxygen vacancies on the surface over Z@B/Bi-Ni by in-situ reduction of Bi^(0) and Ni doping could serve as the active sites for oxygen activation to adsorb free O_(2) and generate more superoxide radicals;(ⅲ)SPR effect of Bi metal were beneficial to carrier separation and also act as the active site to trap O_(2) molecules.This work clarified the role of unique morphologies,surface plasmonic resonance(SPR)effect of metal Bi,and Ni doping in Z@B/Bi-Ni,and its photocatalytic reaction mechanism was proposed by a series of experiments,characterization and DFT calculations,arousing a new perspective to design hierarchical heterojunction photocatalysts.
基金Financial support from the National Research Foundation(NRF)–Nanotechnology Flagship Project[grant number 97823],the DST/Mintek Nanotechnology Innovation Centre–Water Research Node,and the NanoWS4RUMP community engagement project is acknowledged.
文摘Electrospun cyclodextrin(CD)-based nanofibers with capabilities to remove pollutants from water have been synthesized and characterized.The high-quality nanofibers presented here were synthesized in two simple steps that involved in-situ electrospinning of the nanofibers and all nanocomponents,followed by the reduction of silver(Ag+)and iron(Fe3+)ions to nanoparticles using an environmentally benign process that involved irradiation of the electrospun fibers using a tailor-made UV-equipped furnace at low temperatures.In the previously reported study it was observed that Ag and Fe nanoparticles effectively removed a range of different strains of Gram-negative and Gram-positive bacteria from water.As such,this study focused on improving the thermal and mechanical properties of the nanofibers prepared from polymer blends ofβ-CDs with cellulose acetate(CA)and small additions(2 wt%)of functionalized multiwalled carbon nanotubes(fMWCNTs).The electrospinning parameters were varied to determine the optimum conditions for preparation of uniform nonbeaded nanofibers.Bead-free and uniform nanofibers were obtained at a polymer concentration of 32%at the ratio of 1:1β-CDs:CA,syringe injection flow rate of 0.7 mL h−1,15 cm between the tip of the spinneret and the collector,and a voltage of 16 kV.The addition of f-MWCNTs was found to improve the tensile strength of the nanofibers by twofold,relative to nanofibers with no f-MWCNTs.The thermal degradation of the nanofibers was improved by a magnitude of 50°C.The study has shown that adding small amounts of f-MWCNTs improved the thermal stability and mechanical strength of the CD/CA nanofibers significantly.
