The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts hav...The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts have high activity and stability,which are important in reducing the cost of hydrogen production and promoting the development of the hydrogen production industry.However,there is a lack of discussion regarding the effect of carbon components on the performance of these electrocatalysts.This review of the literature discusses the choice of the carbon components in these catalysts and their impact on catalytic performance,including electronic structure control by heteroatom doping,morphology adjustment,and the influence of self-supporting materials.It not only analyzes the progress in HER,but also provides guidance for synthesizing high-performance carbon-based transition metal catalysts.展开更多
Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion lumi...Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion luminescence intensities was reported for NaYF_(4)∶Yb/Er nanophosphors by a facile hydrothermal procedure with different surfactants.With the change of the surfactants from polyvinylpyrrolidone(PVP)to sodium citrate(CIT),edetate disodium(EDTA)or sodium dodecyl benzenesulfonate(SDBS),the morphology of NaYF_(4)∶Yb/Er nanophosphors transformed from nanoparticles with a diameter of about 70.0 nm to hexagonal nanoblocks with a thickness of about 125.0 nm and a length of about 240.0 nm,nanorods with a diameter of about 700.0 nm and a length of about 2.6μm,or nanowires with a diameter of 250.0 nm and a length of about 3.2μm.Simultaneously,their up-conversion luminescence intensity went down gradually under laser irradiation at a wavelength of 980 nm due to the increase of photobleaching.PVP-capped NaYF_(4)∶Yb/Er nanoparticles exhibited the smallest size and the strongest up-conversion luminescence intensity.Biological experiment results revealed that NaYF_(4)∶Yb/Er nanophosphors exhibited a high biocompatibility and could be used as biological labels with a perfect signal-to-noise ratio for cancer cell imaging.展开更多
Photocatalysis is an efective means to solve the greenhouse efect caused by the large amount of carbon dioxide(CO_(2))emissions from fossil fuel consumption.Graphitic carbon nitride(g-C_(3)N_(4))has the advantages of ...Photocatalysis is an efective means to solve the greenhouse efect caused by the large amount of carbon dioxide(CO_(2))emissions from fossil fuel consumption.Graphitic carbon nitride(g-C_(3)N_(4))has the advantages of suitable band gap,easy preparation,low price,and good stability,making it a promising semiconductor photocatalyst.However,bulk g-C3N4 also has disadvantages such as low gas adsorption,low photocatalytic efciency,narrow spectral response,and easy recombination of electron–hole pairs.The modifcation method based on g-C_(3)N_(4) photocatalyst helps to improve the above-mentioned problems.This review summarizes the research progress in recent years from four aspects:morphology adjustment,co-catalysts,heterostructures and doping.Each aspect includes the pros and cons of diferent improvement methods,the comparison of theoretical calculations and experimental results,the application of diferent characterization methods,and the detailed listing of product yield and selectivity.Prior to this,there was an explanation of the basic theory of semiconductor photocatalytic CO_(2) reduction.Finally,the future challenges and development prospects are also briefy prospected.展开更多
文摘The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts have high activity and stability,which are important in reducing the cost of hydrogen production and promoting the development of the hydrogen production industry.However,there is a lack of discussion regarding the effect of carbon components on the performance of these electrocatalysts.This review of the literature discusses the choice of the carbon components in these catalysts and their impact on catalytic performance,including electronic structure control by heteroatom doping,morphology adjustment,and the influence of self-supporting materials.It not only analyzes the progress in HER,but also provides guidance for synthesizing high-performance carbon-based transition metal catalysts.
基金Shanghai Academic Research Leader,China(No.20XD1420200)Shanghai Shuguang Program,China(No.18SG29)。
文摘Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion luminescence intensities was reported for NaYF_(4)∶Yb/Er nanophosphors by a facile hydrothermal procedure with different surfactants.With the change of the surfactants from polyvinylpyrrolidone(PVP)to sodium citrate(CIT),edetate disodium(EDTA)or sodium dodecyl benzenesulfonate(SDBS),the morphology of NaYF_(4)∶Yb/Er nanophosphors transformed from nanoparticles with a diameter of about 70.0 nm to hexagonal nanoblocks with a thickness of about 125.0 nm and a length of about 240.0 nm,nanorods with a diameter of about 700.0 nm and a length of about 2.6μm,or nanowires with a diameter of 250.0 nm and a length of about 3.2μm.Simultaneously,their up-conversion luminescence intensity went down gradually under laser irradiation at a wavelength of 980 nm due to the increase of photobleaching.PVP-capped NaYF_(4)∶Yb/Er nanoparticles exhibited the smallest size and the strongest up-conversion luminescence intensity.Biological experiment results revealed that NaYF_(4)∶Yb/Er nanophosphors exhibited a high biocompatibility and could be used as biological labels with a perfect signal-to-noise ratio for cancer cell imaging.
基金This research was supported by Key Program for International S&T Cooperation Program of China(2017YFE0113000)the National Natural Science Foundation of China(51971133,51801121,51902200,and 52072241)+2 种基金the Shanghai Science and Technology Committee(18JC1410500,19JC1410400,19ZR1425100,and 18ZR1420900)the National Key Research and Development Program(YS2017YFGH000385)State Key Laboratory for Modifcation of Chemical Fibers and Polymer Materials,Donghua University.
文摘Photocatalysis is an efective means to solve the greenhouse efect caused by the large amount of carbon dioxide(CO_(2))emissions from fossil fuel consumption.Graphitic carbon nitride(g-C_(3)N_(4))has the advantages of suitable band gap,easy preparation,low price,and good stability,making it a promising semiconductor photocatalyst.However,bulk g-C3N4 also has disadvantages such as low gas adsorption,low photocatalytic efciency,narrow spectral response,and easy recombination of electron–hole pairs.The modifcation method based on g-C_(3)N_(4) photocatalyst helps to improve the above-mentioned problems.This review summarizes the research progress in recent years from four aspects:morphology adjustment,co-catalysts,heterostructures and doping.Each aspect includes the pros and cons of diferent improvement methods,the comparison of theoretical calculations and experimental results,the application of diferent characterization methods,and the detailed listing of product yield and selectivity.Prior to this,there was an explanation of the basic theory of semiconductor photocatalytic CO_(2) reduction.Finally,the future challenges and development prospects are also briefy prospected.
