Surface modification on photocatalytic thin films is long considered as an effective strategy to improve the degradation performance,which in turn helps to alleviate the worldwide environmental pollution issue.In this...Surface modification on photocatalytic thin films is long considered as an effective strategy to improve the degradation performance,which in turn helps to alleviate the worldwide environmental pollution issue.In this study,a direct Z-scheme photocatalytic system is constructed successfully by integrating black phosphorus quantum dots(BPQDs)on the surface of BiOBr thin film prepared by hydrothermal method.The optimal BPQDs/BiOBr-1 thin film presents remarkable enhanced photocatalytic activity for degrading methyl violet(MV)and tetracycline hydrochloride(TC),which is 3 and 3.65 times higher than that of pure BiOBr counterpart.The active species involved in the reaction are^(+),·O_(2)^(-),and·OH,which determined by radical trapping experiments.The formation of direct Z-scheme photocatalytic system makes electrons assembled in the conduction band(CB)of BPQDs and holes gathered in the valence band(VB)of BiOBr,which supports the generation of h^(+)and·O_(2)^(-)and in turn accelerates the photocatalytic reaction.Besides,the improved efficiency of charge separation,enhanced visible light absorption and enlarged specific surface area also contributed to the enhanced photocatalytic performance of BPQDs/BiOBr.This work provides a feasible strategy for optimizing photocatalytic thin films via detailed analyzing the role of BPQDs in the construction of direct Z-scheme photocatalysts.展开更多
In this work,a novel dual Z-scheme Bi_(2)WO_(6)/g-C_(3)N_(4)/black phosphorus quantum dots(Bi_(2)WO_(6)/g-C_(3)N_(4)/BPQDs)composites were fabricated and utilized towards photocatalytic degradation of bisphenol A(BPA)...In this work,a novel dual Z-scheme Bi_(2)WO_(6)/g-C_(3)N_(4)/black phosphorus quantum dots(Bi_(2)WO_(6)/g-C_(3)N_(4)/BPQDs)composites were fabricated and utilized towards photocatalytic degradation of bisphenol A(BPA)under visible-light irradiation.Optimizing the content of g-C_(3)N_(4) and BPQDs in Bi_(2)WO_(6)/g-C_(3)N_(4)/BPQDs composites to a suitable mass ratio can enhance the visible-light harvesting capacity and increase the charge separation efficiency and the transfer rate of excited-state electrons and holes,resulting in much higher photocatalytic activity for BPA degradation(95.6%,at 20 mg/L in 120 min)than that of Bi2WO6(63.7%),g-C_(3)N_(4)(25.0%),BPQDs(8.5%),and Bi_(2)WO_(6)/g-C_(3)N_(4)(79.6%),respectively.Radical trapping experiments indicated that photogenerated holes(h+)and superoxide radicals(•O_(2)−)played crucial roles in photocatalytic BPA degradation.Further,the possible degradation pathway and photocatalytic mechanism was proposed by analyzing the BPA intermediates.Thiswork also demonstrated that the Bi2WO6/g-C_(3)N_(4)/BPQDs as effective photocatalystswas stable and have promising potential to remove environmental contaminants from real water samples.展开更多
Intervertebral disc degeneration(IVDD)is commonly caused by imbalanced oxygen metabolism-triggered inflammation.Overcoming the shortcomings of antioxidants in IVDD treatment,including instability and the lack of targe...Intervertebral disc degeneration(IVDD)is commonly caused by imbalanced oxygen metabolism-triggered inflammation.Overcoming the shortcomings of antioxidants in IVDD treatment,including instability and the lack of targeting,remains challenging.Microfluidic and surface modification technologies were combined to graft chitosan nanoparticles encapsulated with strong reductive black phosphorus quantum dots(BPQDs)onto GelMA microspheres via amide bonds to construct oxygen metabolism-balanced engineered hydrogel microspheres(GM@CS-BP),which attenuate extracellular acidosis in nucleus pulposus(NP),block the inflammatory cascade,reduce matrix metalloproteinase expression(MMP),and remodel the extracellular matrix(ECM)in intervertebral discs(IVDs).The GM@CS-BP microspheres reduce H_(2)O_(2) intensity by 229%.Chemical grafting and electrostatic attraction increase the encapsulation rate of BPQDs by 167%and maintain stable release for 21 days,demonstrating the antioxidant properties and sustained modulation of the BPQDs.After the GM@CS-BP treatment,western blotting revealed decreased acid-sensitive ion channel-3 and inflammatory factors.Histological staining in an 8-week IVDD model confirmed the regeneration of NP.GM@CS-BP microspheres therefore maintain a balance between ECM synthesis and degradation by regulating the positive feedback between imbalanced oxygen metabolism in IVDs and inflammation.This study provides an in-depth interpretation of the mechanisms underlying the antioxidation of BPQDs and a new approach for IVDD treatment.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.52002301,U1806221,51672198)Natural Science Foundation of Hubei Province(Grant No.2020CFB308)+4 种基金Start-up Funding ofWuhan University of Technology(Grant No.40120490)Innovation and Development Project of Zibo City(2017 C×01 A022)Instruction&Development Project for National Funding Innovation Demonstration Zone of Shandong Province(2016-181-11,2017-41-1,2017-41-3,2018ZCQZB01,2019ZCQZB03)Central Guiding Local Science and Technology Development Special Funds(Grant Nos.2060503)Key Research&Design Program of Shandong Province(2019GGX102011).
文摘Surface modification on photocatalytic thin films is long considered as an effective strategy to improve the degradation performance,which in turn helps to alleviate the worldwide environmental pollution issue.In this study,a direct Z-scheme photocatalytic system is constructed successfully by integrating black phosphorus quantum dots(BPQDs)on the surface of BiOBr thin film prepared by hydrothermal method.The optimal BPQDs/BiOBr-1 thin film presents remarkable enhanced photocatalytic activity for degrading methyl violet(MV)and tetracycline hydrochloride(TC),which is 3 and 3.65 times higher than that of pure BiOBr counterpart.The active species involved in the reaction are^(+),·O_(2)^(-),and·OH,which determined by radical trapping experiments.The formation of direct Z-scheme photocatalytic system makes electrons assembled in the conduction band(CB)of BPQDs and holes gathered in the valence band(VB)of BiOBr,which supports the generation of h^(+)and·O_(2)^(-)and in turn accelerates the photocatalytic reaction.Besides,the improved efficiency of charge separation,enhanced visible light absorption and enlarged specific surface area also contributed to the enhanced photocatalytic performance of BPQDs/BiOBr.This work provides a feasible strategy for optimizing photocatalytic thin films via detailed analyzing the role of BPQDs in the construction of direct Z-scheme photocatalysts.
基金supported by the National Natural Science Foundation of China (No. 21964006)the Hunan Provincial Natural Science Foundation of China (No. 2020JJ4640)+1 种基金the Scientific Research Fund of Hunan Provincial Education Department (No. 20A050)the Scientific Research Found of Changsha University (No. SF1934)
文摘In this work,a novel dual Z-scheme Bi_(2)WO_(6)/g-C_(3)N_(4)/black phosphorus quantum dots(Bi_(2)WO_(6)/g-C_(3)N_(4)/BPQDs)composites were fabricated and utilized towards photocatalytic degradation of bisphenol A(BPA)under visible-light irradiation.Optimizing the content of g-C_(3)N_(4) and BPQDs in Bi_(2)WO_(6)/g-C_(3)N_(4)/BPQDs composites to a suitable mass ratio can enhance the visible-light harvesting capacity and increase the charge separation efficiency and the transfer rate of excited-state electrons and holes,resulting in much higher photocatalytic activity for BPA degradation(95.6%,at 20 mg/L in 120 min)than that of Bi2WO6(63.7%),g-C_(3)N_(4)(25.0%),BPQDs(8.5%),and Bi_(2)WO_(6)/g-C_(3)N_(4)(79.6%),respectively.Radical trapping experiments indicated that photogenerated holes(h+)and superoxide radicals(•O_(2)−)played crucial roles in photocatalytic BPA degradation.Further,the possible degradation pathway and photocatalytic mechanism was proposed by analyzing the BPA intermediates.Thiswork also demonstrated that the Bi2WO6/g-C_(3)N_(4)/BPQDs as effective photocatalystswas stable and have promising potential to remove environmental contaminants from real water samples.
基金supported by the National Natural Science Foundation of China(81972078,82120108017,82072438,82102589,81702190)Social Development Project of Jiangsu Province(BE2021646),Standardized Diagnosis and Treatment Project of Key Diseases in Jiangsu Province(BE2015641)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20211504 and BK20170370)Suzhou Gusu Health Talent Program(GSWS2020001 and GSWS2021007)Jiangsu Innovative and Entrepreneurial Talent Program(JSSCBS20211570)Medical Health Science and Technology Innovation Program of Suzhou(SKY2022119).
文摘Intervertebral disc degeneration(IVDD)is commonly caused by imbalanced oxygen metabolism-triggered inflammation.Overcoming the shortcomings of antioxidants in IVDD treatment,including instability and the lack of targeting,remains challenging.Microfluidic and surface modification technologies were combined to graft chitosan nanoparticles encapsulated with strong reductive black phosphorus quantum dots(BPQDs)onto GelMA microspheres via amide bonds to construct oxygen metabolism-balanced engineered hydrogel microspheres(GM@CS-BP),which attenuate extracellular acidosis in nucleus pulposus(NP),block the inflammatory cascade,reduce matrix metalloproteinase expression(MMP),and remodel the extracellular matrix(ECM)in intervertebral discs(IVDs).The GM@CS-BP microspheres reduce H_(2)O_(2) intensity by 229%.Chemical grafting and electrostatic attraction increase the encapsulation rate of BPQDs by 167%and maintain stable release for 21 days,demonstrating the antioxidant properties and sustained modulation of the BPQDs.After the GM@CS-BP treatment,western blotting revealed decreased acid-sensitive ion channel-3 and inflammatory factors.Histological staining in an 8-week IVDD model confirmed the regeneration of NP.GM@CS-BP microspheres therefore maintain a balance between ECM synthesis and degradation by regulating the positive feedback between imbalanced oxygen metabolism in IVDs and inflammation.This study provides an in-depth interpretation of the mechanisms underlying the antioxidation of BPQDs and a new approach for IVDD treatment.
