Herein, two nanoparticles with different dimensions, spherical carbon dots (C-dots) and sheetlike hectorite clay, were used as physical crosslinkers to fabricate C-dots-clay-poly(N-isopropylacrylamide)nanocompositehyd...Herein, two nanoparticles with different dimensions, spherical carbon dots (C-dots) and sheetlike hectorite clay, were used as physical crosslinkers to fabricate C-dots-clay-poly(N-isopropylacrylamide)nanocompositehydrogels (coded as C-dots-clay-PNIPAm hydrogels). The mechanical properties, fluorescence features and thermal-responsive properties of the C-dots-clay-PNIPAm hydrogels were evaluated. The experimental results indicate that synergistic effects of C-dots and hectorite clay nanoparticles are able to significantly enhance mechanical properties of the hydrogels. The hydrogels can be stretched up to 1730%with strength as high as 250 kPa when the C-dots concentration is 0.1wt%and the clay concentration is 6wt%. The hydrogels exhibit complete self-healing through autonomic reconstruction of crosslinked network a damaged interface. The hydrogels show favorable thermal-responsive properties with the volume phase transition around 34℃. In addition, the hydrogels are endowed with fluorescence features that are associated with C-dots in the hydrogels. It can be expected that the as-fabricated C-dots-clay-PNIPAm hydrogels are promising for applications in sensors, biomedical carriers and tissue engineering.展开更多
Carbon dots(CDs),as a class of promising and multifunctional carbon nanomaterials,have become a research hotspot in the field of photocatalysis owning to strong absorption of visible light,favorable photoelectric prop...Carbon dots(CDs),as a class of promising and multifunctional carbon nanomaterials,have become a research hotspot in the field of photocatalysis owning to strong absorption of visible light,favorable photoelectric properties,and tunable energy-level configuration.Although numerous efforts have been made to improve photocatalytic performance by combining CDs with other semiconductors in recent years,the summary of enhancement mechanisms for this emerging technology is few reported.Fully understanding the synergistic effect of CDs and nanomaterials in photocatalytic applications is extremely important for the further development of photocatalysis in the future.Here,the photocatalytic mechanism of carbon dots/nanomaterial system is discussed.Four typical carbon dots-synergistic enhancement effects are highlighted,namely,energy band regulation,local electric construction,active site engineering,and multiple carrier activation.Second,the recent progress of carbon dots-based nanocomposites in efficient solar energy conversion is reviewed and examples are given.Finally,the future research development direction and challenges are emphasized on this basis.展开更多
Carbon dots(CDs)have gained unprecedented attention as a novel luminescent zero-dimensional carbon nanomaterial owing to their diverse industrial applications.Herein,we reported the sus-tainable synthesis of fluoresce...Carbon dots(CDs)have gained unprecedented attention as a novel luminescent zero-dimensional carbon nanomaterial owing to their diverse industrial applications.Herein,we reported the sus-tainable synthesis of fluorescent CDs from papaya peel waste,acting as a natural carbon orig-inator.As-prepared CDs and reduced graphene oxide(RGO)were fabricated in the composites through a facile one-step hydrothermal method.Synthesized RGO/CDs(RC)nanocomposites were characterized using spectroscopic,diffraction,and electron-microscopic techniques.Nanocom-posites with variable RGO to CD mass ratios were tested for photodegradation of textile dye methylene blue(MB).The highest photocatalytic activity(degradation efficiency of 87%in 135 min)was obtained in the nanocomposite containing a 2꞉1 mass ratio(RC2).The RGO sheets in the nanocomposite acted as media for electron acceptors,promoting the fast transfer and sep-aration of photoinduced electrons during CDs excitation,thus preventing the recombination of the electron and holes.Based on the agar well diffusion assay,the nanocomposites exhibited ex-cellent antibacterial activity than other tested materials against Bacillus subtilis(Gram-positive)and Pseudomonas aeruginosa(Gram-negative)bacterium.The largest inhibition zone area(22 mm),i.e.,the highest antimicrobial activity,was obtained in the nanocomposite tested against Gram-positive strains.Taken together,the synergistic effect of RGO and CDs enhanced the pho-tocatalytic and antibacterial performance of synthesized nanocomposite material.展开更多
Nanocomposite hydrogels based on carbon dots(CDs)and polymers have emerged as new materials with integrated properties of individual components,leading to their important applications in the field of soft nanomaterial...Nanocomposite hydrogels based on carbon dots(CDs)and polymers have emerged as new materials with integrated properties of individual components,leading to their important applications in the field of soft nanomaterials.This perspective highlights recent advances in the development of nanocomposite hydrogels from CDs and polymers.We review the preparation methods of nanocomposite hydrogels based on CDs and polymers,and emerging applications of these nanocomposite hydrogels such as environmental remediation,energy storage,sensing,drug delivery and bioimaging.We conclude with the discussion of new research directions in the development of new type of nanocomposite hydrogels based on CDs and polymers.展开更多
Zero-dimensional carbon dots have emerged as important nanofillers for the separation membrane due to their small specific size and rich surface functional groups.This study proposed a strategy based on hydrophobic ca...Zero-dimensional carbon dots have emerged as important nanofillers for the separation membrane due to their small specific size and rich surface functional groups.This study proposed a strategy based on hydrophobic carbon dots(HCDs)to regulate water channels for an efficient forward osmosis(FO)membrane.Thin-film composite(TFC)membranes with superior FO performance are fabricated by introducing HCDs as the nanofiller in the polyacrylonitrile support layer.The introduction of HCDs promotes the formation of the support layer with coherent finger-like hierarchical channels and micro-convex structure and an integrated polyamide active layer.Compared to the original membrane,TFC-FO membrane with 10 wt%HCDs exhibits high water flux(15.47 L m^(-2)h^(-1))and low reverse salt flux(2.9 g m^(-2)h^(-1))using 1 mol/L Na Cl as the draw solution.This improved FO performance is attributed to the lower structural parameters of HCDs-induced water channels and alleviated internal concentration polarization.Thus,this paper provides a feasible strategy to design the membrane structure and boost FO performance.展开更多
基金the National Natural Science Foundation of China(Nos.51873167 and 50803048)the 2018 National College Students Innovation and Entrepreneurship Training Program Project Funding(No.20181049701035)。
文摘Herein, two nanoparticles with different dimensions, spherical carbon dots (C-dots) and sheetlike hectorite clay, were used as physical crosslinkers to fabricate C-dots-clay-poly(N-isopropylacrylamide)nanocompositehydrogels (coded as C-dots-clay-PNIPAm hydrogels). The mechanical properties, fluorescence features and thermal-responsive properties of the C-dots-clay-PNIPAm hydrogels were evaluated. The experimental results indicate that synergistic effects of C-dots and hectorite clay nanoparticles are able to significantly enhance mechanical properties of the hydrogels. The hydrogels can be stretched up to 1730%with strength as high as 250 kPa when the C-dots concentration is 0.1wt%and the clay concentration is 6wt%. The hydrogels exhibit complete self-healing through autonomic reconstruction of crosslinked network a damaged interface. The hydrogels show favorable thermal-responsive properties with the volume phase transition around 34℃. In addition, the hydrogels are endowed with fluorescence features that are associated with C-dots in the hydrogels. It can be expected that the as-fabricated C-dots-clay-PNIPAm hydrogels are promising for applications in sensors, biomedical carriers and tissue engineering.
基金supported by the National Natural Science Foundation of China(Grant No.22272019)Sichuan Science and Technology Program(Nos.2022ZYD0039 and 2023NSFSC1069).
文摘Carbon dots(CDs),as a class of promising and multifunctional carbon nanomaterials,have become a research hotspot in the field of photocatalysis owning to strong absorption of visible light,favorable photoelectric properties,and tunable energy-level configuration.Although numerous efforts have been made to improve photocatalytic performance by combining CDs with other semiconductors in recent years,the summary of enhancement mechanisms for this emerging technology is few reported.Fully understanding the synergistic effect of CDs and nanomaterials in photocatalytic applications is extremely important for the further development of photocatalysis in the future.Here,the photocatalytic mechanism of carbon dots/nanomaterial system is discussed.Four typical carbon dots-synergistic enhancement effects are highlighted,namely,energy band regulation,local electric construction,active site engineering,and multiple carrier activation.Second,the recent progress of carbon dots-based nanocomposites in efficient solar energy conversion is reviewed and examples are given.Finally,the future research development direction and challenges are emphasized on this basis.
文摘Carbon dots(CDs)have gained unprecedented attention as a novel luminescent zero-dimensional carbon nanomaterial owing to their diverse industrial applications.Herein,we reported the sus-tainable synthesis of fluorescent CDs from papaya peel waste,acting as a natural carbon orig-inator.As-prepared CDs and reduced graphene oxide(RGO)were fabricated in the composites through a facile one-step hydrothermal method.Synthesized RGO/CDs(RC)nanocomposites were characterized using spectroscopic,diffraction,and electron-microscopic techniques.Nanocom-posites with variable RGO to CD mass ratios were tested for photodegradation of textile dye methylene blue(MB).The highest photocatalytic activity(degradation efficiency of 87%in 135 min)was obtained in the nanocomposite containing a 2꞉1 mass ratio(RC2).The RGO sheets in the nanocomposite acted as media for electron acceptors,promoting the fast transfer and sep-aration of photoinduced electrons during CDs excitation,thus preventing the recombination of the electron and holes.Based on the agar well diffusion assay,the nanocomposites exhibited ex-cellent antibacterial activity than other tested materials against Bacillus subtilis(Gram-positive)and Pseudomonas aeruginosa(Gram-negative)bacterium.The largest inhibition zone area(22 mm),i.e.,the highest antimicrobial activity,was obtained in the nanocomposite tested against Gram-positive strains.Taken together,the synergistic effect of RGO and CDs enhanced the pho-tocatalytic and antibacterial performance of synthesized nanocomposite material.
基金financially supported by the National Natural Science Foundation of China(NSFC,Nos.21774041,51433003)the National Key Research and Development Program of China(No.2016YFB0401701)+1 种基金the Fundamental Research Funds for the Central Universities,Program for JLU Science and Technology Innovative Research Team(JLUSTIRT,No.2017TD-06)the opening funds of State Key Laboratory of Applied Optics,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences。
文摘Nanocomposite hydrogels based on carbon dots(CDs)and polymers have emerged as new materials with integrated properties of individual components,leading to their important applications in the field of soft nanomaterials.This perspective highlights recent advances in the development of nanocomposite hydrogels from CDs and polymers.We review the preparation methods of nanocomposite hydrogels based on CDs and polymers,and emerging applications of these nanocomposite hydrogels such as environmental remediation,energy storage,sensing,drug delivery and bioimaging.We conclude with the discussion of new research directions in the development of new type of nanocomposite hydrogels based on CDs and polymers.
基金financially supported by the National Key Research and Development Project(No.2019YFC1907801)the Hunan Provincial Science and Technology Plan Projects(No.2019JJ30031)the Innovation-Driven Project of Central South University(No.2020CX007)。
文摘Zero-dimensional carbon dots have emerged as important nanofillers for the separation membrane due to their small specific size and rich surface functional groups.This study proposed a strategy based on hydrophobic carbon dots(HCDs)to regulate water channels for an efficient forward osmosis(FO)membrane.Thin-film composite(TFC)membranes with superior FO performance are fabricated by introducing HCDs as the nanofiller in the polyacrylonitrile support layer.The introduction of HCDs promotes the formation of the support layer with coherent finger-like hierarchical channels and micro-convex structure and an integrated polyamide active layer.Compared to the original membrane,TFC-FO membrane with 10 wt%HCDs exhibits high water flux(15.47 L m^(-2)h^(-1))and low reverse salt flux(2.9 g m^(-2)h^(-1))using 1 mol/L Na Cl as the draw solution.This improved FO performance is attributed to the lower structural parameters of HCDs-induced water channels and alleviated internal concentration polarization.Thus,this paper provides a feasible strategy to design the membrane structure and boost FO performance.
