White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual healt...White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light.展开更多
It is attractive and encouraging to develop new fluorescent carbon dots(CDs)with excellent optical properties and promising applications prospects.Herein,highly-efficient green emissive CDs(m-CDs)with a high quantum y...It is attractive and encouraging to develop new fluorescent carbon dots(CDs)with excellent optical properties and promising applications prospects.Herein,highly-efficient green emissive CDs(m-CDs)with a high quantum yield(QY)of 71.7%in water are prepared through a facile solvothermal method.Interestingly,the m-CDs exhibit excellent fluorescence stability in the pH range of 1–9.However,the fluorescence intensity of the m-CDs is almost completely quenched as the pH is increased from 9 to 10.The mechanism of the unique pH-responsive behavior is discussed in detail and a plausible mechanism is proposed.Owing to the unique pH-responsive behavior,the m-CDs are used as a on-off fluorescent probe for water quality identification.By combining the reversible pH-ultrasensitive optical properties of the m-CDs in the pH range of 9–10 with the glucose oxidase-mimicking(GOx-mimicking)ability of Au nanoparticles(AuNPs),glucose can be quantitatively detected.Finally,two environment-friendly starch-based solid-state fluorescence materials(powder and film)are developed through green preparation routes.展开更多
High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis methods.In this work,we exploited an easy-to-i...High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis methods.In this work,we exploited an easy-to-implement strategy for the one-step synthesis of green-emitting CDs(G-CDs)with superb optical properties.The G-CDs were synthesized using m-phenylenediamine(m-PD)as a single precursor,and the reaction reacted at 180℃for 12 h The resultant G-CDs exhibit high-purity and excitationindependent green fluorescence with the photoluminescence(PL)peak located at 516 nm,full width at half maximum(FWHM)of 46 nm,and PL quantum yield(QY)of∼80%under the 470nm excitation light.The G-CDs and corresponding composite film prepared with polyvinyl butyral(G-CDs@PVB)exhibit good PL stability after undergoing long-time storage for one year and 360 h exposure under 460nm blue light.The G-CDs@PVB film was used as color-conversion materials in green-emitting light-emitting diode(LED)application,exhibiting a Commission internationale de l’Eclairage(CIE)chromaticity coordinate of(0.21,0.44).The film was also used in CD-based liquid crystal display(CD-LCD)application,achieving a color gamut value of 85%.This work will offer a working basis for the synthesis of high-performance CDs as well as their application in displays.展开更多
Carbon dots(CDs),as a solid-state phosphor,have great potential for application in a new solid-state lighting device—laser diode(LD).For high efficiency LD devices,both high photoluminescence quantum yield(PLQY)and h...Carbon dots(CDs),as a solid-state phosphor,have great potential for application in a new solid-state lighting device—laser diode(LD).For high efficiency LD devices,both high photoluminescence quantum yield(PLQY)and high photothermal stability of CDs are essential.Herein,yellow CDs@ZIF-8 composites with high structural stability were prepared by encapsulating CDs in zeolitic imidazolate framework-8(ZIF-8)through electrostatic adsorption between CDs and ZIF-8,in which CDs with amino groups on the surface were used as luminescent feeders and ZIF-8 was used as a protective layer matrix.The asprepared CDs@ZIF-8 not only possess a high PLQY of up to 81.17%,but also maintain a high fluorescence intensity of 100%and 80%under long-term illumination(60 min)and high temperature(478 K),respectively.The hydrogen bonding between CDs and ZIF-8 in the encapsulated structure can enhance the degree of electron cloud delocalization,which can improve the PLQY of CDs@ZIF-8.Meanwhile,CDs@ZIF-8has high photothermal stability due to the binding effect of ZIF-8 on CDs and high thermal stability of ZIF-8.The white LD device,fabricated from CDs@ZIF-8 as a phosphor in combination with 450 nm blue LD,has a color coordinate of(0.37,0.33),a color temperature of 3762 K,and a high color rendering index of 86.This study provides a new strategy for the construction of solid-state phosphors with high PLQY and high photothermal performance.展开更多
Spark, stream and corona pulsed high-voltage discharges in water induced by the various initial conductivities have been examined in this paper. The discharge modes changed from spark to corona discharge with the liqu...Spark, stream and corona pulsed high-voltage discharges in water induced by the various initial conductivities have been examined in this paper. The discharge modes changed from spark to corona discharge with the liquid conductivity increasing. The apparent production of OH radical and quantum yield generated by spark discharge in distilled water were 11.57 ìmol/L and 0.0978 photon/s, respectively. A preliminary study on acid fuchsine (AF) treatment indicated that higher AF removal efficiency has been achieved by spark discharge. The process of degradation showed that the oxidative effects through OH radical oxidation did not play an important role and did increase with the discharge mode changing to spark discharge.展开更多
Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still ...Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still face challenges in terms of low phosphorescence quantum yields and limited long persistent luminescence(LPL)colors.Herein,we present the design and synthesis of an intraligand chargetransfer organic-based metal halide perovskite-like material,in which organic cations form a compact supramolecular hydrogen-bonded organic framework(HOF)structure,exhibiting crystallization-induced phosphorescence emission of ligand,while metal halides form a unique two-dimensional(2D)structure that displays intrinsic self-trapped excitons(STE)emission under the radiation of UV light.Notably,the metal halide hybrid is found to exhibit enhanced phosphorescent photoluminescence efficiency of up to 81.05%and tunable LPL from cyan to orange compared to the pristine organic phosphor,due to the structural distortion and scaffolding effects of 2D metal halides as well as a well-packed HOF structure.Optical characterizations and theoretical calculations reveal that charge transfer from organic cations and halogen to ligand as well as STE from inorganic layers are responsible for the tunable LPL.Meanwhile,the high-efficiency phosphorescent quantum yield is attributed to stronger hydrogen bond stacking as well as structural distortion of metal halogen bands.Thus,the obtained LPL provides potentials in anti-counterfeiting,security systems,and so on.展开更多
Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lowe...Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lower quantum yield(QY)still limits its wide application.Herein,we reported a novel and convenient strategy to prepare photo-induced Ag/CDs(p-Ag/CDs)by irradiating the mixed Ag+and hydrophobic CDs(h-CDs)acetone solution with ultraviolet(UV)light.The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift(460 nm)than h-CDs(520 nm).The QY of p-Ag/CDs is measured to be 51.1%,which is 10.4 times higher than that of h-CDs(4.9%),indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs.The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail.The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles(AgNPs)by UV light irradiation based on metal-enhanced fluorescence(MEF),and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence.Interestingly,the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions(S2-)detection than that of h-CDs,which have a lower response to S2-.This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields.展开更多
基金supported by Medical Science and Technology Research Project of Henan Province(Joint Construction Project)(No.LHGJ20200433)National Natural Science Foundation of China(No.52122308)。
文摘White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light.
基金supported by the National Natural Science Foundation of China(Nos.21375123,21675151,and 21721003)the Ministry of Science and Technology of China(No.2016YFA0203203).
文摘It is attractive and encouraging to develop new fluorescent carbon dots(CDs)with excellent optical properties and promising applications prospects.Herein,highly-efficient green emissive CDs(m-CDs)with a high quantum yield(QY)of 71.7%in water are prepared through a facile solvothermal method.Interestingly,the m-CDs exhibit excellent fluorescence stability in the pH range of 1–9.However,the fluorescence intensity of the m-CDs is almost completely quenched as the pH is increased from 9 to 10.The mechanism of the unique pH-responsive behavior is discussed in detail and a plausible mechanism is proposed.Owing to the unique pH-responsive behavior,the m-CDs are used as a on-off fluorescent probe for water quality identification.By combining the reversible pH-ultrasensitive optical properties of the m-CDs in the pH range of 9–10 with the glucose oxidase-mimicking(GOx-mimicking)ability of Au nanoparticles(AuNPs),glucose can be quantitatively detected.Finally,two environment-friendly starch-based solid-state fluorescence materials(powder and film)are developed through green preparation routes.
基金supported by the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB369)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis methods.In this work,we exploited an easy-to-implement strategy for the one-step synthesis of green-emitting CDs(G-CDs)with superb optical properties.The G-CDs were synthesized using m-phenylenediamine(m-PD)as a single precursor,and the reaction reacted at 180℃for 12 h The resultant G-CDs exhibit high-purity and excitationindependent green fluorescence with the photoluminescence(PL)peak located at 516 nm,full width at half maximum(FWHM)of 46 nm,and PL quantum yield(QY)of∼80%under the 470nm excitation light.The G-CDs and corresponding composite film prepared with polyvinyl butyral(G-CDs@PVB)exhibit good PL stability after undergoing long-time storage for one year and 360 h exposure under 460nm blue light.The G-CDs@PVB film was used as color-conversion materials in green-emitting light-emitting diode(LED)application,exhibiting a Commission internationale de l’Eclairage(CIE)chromaticity coordinate of(0.21,0.44).The film was also used in CD-based liquid crystal display(CD-LCD)application,achieving a color gamut value of 85%.This work will offer a working basis for the synthesis of high-performance CDs as well as their application in displays.
基金financially supported by the Foundational Research Project of Shanxi Province(No.20210302123164)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(Nos.2022SX-TD012,2021SX-TD012)Shanxi Scholarship Council of China(No.2020–051)。
文摘Carbon dots(CDs),as a solid-state phosphor,have great potential for application in a new solid-state lighting device—laser diode(LD).For high efficiency LD devices,both high photoluminescence quantum yield(PLQY)and high photothermal stability of CDs are essential.Herein,yellow CDs@ZIF-8 composites with high structural stability were prepared by encapsulating CDs in zeolitic imidazolate framework-8(ZIF-8)through electrostatic adsorption between CDs and ZIF-8,in which CDs with amino groups on the surface were used as luminescent feeders and ZIF-8 was used as a protective layer matrix.The asprepared CDs@ZIF-8 not only possess a high PLQY of up to 81.17%,but also maintain a high fluorescence intensity of 100%and 80%under long-term illumination(60 min)and high temperature(478 K),respectively.The hydrogen bonding between CDs and ZIF-8 in the encapsulated structure can enhance the degree of electron cloud delocalization,which can improve the PLQY of CDs@ZIF-8.Meanwhile,CDs@ZIF-8has high photothermal stability due to the binding effect of ZIF-8 on CDs and high thermal stability of ZIF-8.The white LD device,fabricated from CDs@ZIF-8 as a phosphor in combination with 450 nm blue LD,has a color coordinate of(0.37,0.33),a color temperature of 3762 K,and a high color rendering index of 86.This study provides a new strategy for the construction of solid-state phosphors with high PLQY and high photothermal performance.
文摘Spark, stream and corona pulsed high-voltage discharges in water induced by the various initial conductivities have been examined in this paper. The discharge modes changed from spark to corona discharge with the liquid conductivity increasing. The apparent production of OH radical and quantum yield generated by spark discharge in distilled water were 11.57 ìmol/L and 0.0978 photon/s, respectively. A preliminary study on acid fuchsine (AF) treatment indicated that higher AF removal efficiency has been achieved by spark discharge. The process of degradation showed that the oxidative effects through OH radical oxidation did not play an important role and did increase with the discharge mode changing to spark discharge.
基金National Natural Science Foundation of China,Grant/Award Numbers:22101162,92261114。
文摘Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still face challenges in terms of low phosphorescence quantum yields and limited long persistent luminescence(LPL)colors.Herein,we present the design and synthesis of an intraligand chargetransfer organic-based metal halide perovskite-like material,in which organic cations form a compact supramolecular hydrogen-bonded organic framework(HOF)structure,exhibiting crystallization-induced phosphorescence emission of ligand,while metal halides form a unique two-dimensional(2D)structure that displays intrinsic self-trapped excitons(STE)emission under the radiation of UV light.Notably,the metal halide hybrid is found to exhibit enhanced phosphorescent photoluminescence efficiency of up to 81.05%and tunable LPL from cyan to orange compared to the pristine organic phosphor,due to the structural distortion and scaffolding effects of 2D metal halides as well as a well-packed HOF structure.Optical characterizations and theoretical calculations reveal that charge transfer from organic cations and halogen to ligand as well as STE from inorganic layers are responsible for the tunable LPL.Meanwhile,the high-efficiency phosphorescent quantum yield is attributed to stronger hydrogen bond stacking as well as structural distortion of metal halogen bands.Thus,the obtained LPL provides potentials in anti-counterfeiting,security systems,and so on.
基金the National Natural Science Foundation of China(Nos.U1833202 and 21876117)the Open Research Fund of the School of Chemistry and Chemical Engineering,Henan Normal University(No.2021YB05).
文摘Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lower quantum yield(QY)still limits its wide application.Herein,we reported a novel and convenient strategy to prepare photo-induced Ag/CDs(p-Ag/CDs)by irradiating the mixed Ag+and hydrophobic CDs(h-CDs)acetone solution with ultraviolet(UV)light.The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift(460 nm)than h-CDs(520 nm).The QY of p-Ag/CDs is measured to be 51.1%,which is 10.4 times higher than that of h-CDs(4.9%),indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs.The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail.The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles(AgNPs)by UV light irradiation based on metal-enhanced fluorescence(MEF),and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence.Interestingly,the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions(S2-)detection than that of h-CDs,which have a lower response to S2-.This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields.
