Converting sustainable solar energy into hydrogen energy over semiconductor-based photocatalytic materials provides an alternative to fossil fuel consumption.However,efficient photocatalytic splitting of water to real...Converting sustainable solar energy into hydrogen energy over semiconductor-based photocatalytic materials provides an alternative to fossil fuel consumption.However,efficient photocatalytic splitting of water to realize carbon-free hydrogen production remains a challenge.Heterojunction photocatalysts with well-defined dimensionality and perfectly matched interfaces are promising for achieving highly efficient solar-to-hydrogen conversion.Herein,we report the fabrication of a novel type of protonated graphitic carbon nitride(PCN)/Ti3C2 MXene heterojunctions with strong interfacial interactions.As expected,the two-dimensional(2D)PCN/2D Ti3C2 MXene interface heterojunction achieves a highly improved hydrogen evolution rate(2181μmol∙g‒1)in comparison with bulk g-C3N4(393μmol∙g‒1)and protonated g-C3N4(816μmol∙g‒1).The charge-regulated surfaces of PCN and the accelerated charge transport at the face-to-face 2D/2D Schottky heterojunction interface are the major contributors to the excellent hydrogen evolution performance of the composite photocatalyst.展开更多
Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from...Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from certain limitations,such as poor visible-light utilization,rapid recombination of charge carriers,and low catalytic capability.The key challenge is to develop visible-light-driven heterojunction photocatalysts that are stable and highly active during the water splitting process.Here,we demonstrate the integration of one-dimensional(1D)Cd S nanorods with two-dimensional(2D)1 T-phase dominated WS_(2) nanosheets for constructing mixed-dimensional heterojunctions for the photocatalytic hydrogen evolution reaction(HER).The resulting 1D CdS/2D WS_(2) nanoheterojunction exhibited an ultrahigh hydrogen-evolution activity of~70 mmol·g^(-1)·h^(-1) that was visible to the naked eye,as well as long-term stability under visible light illumination.The results reveal that the synergy of hybrid nanoarchitectures and intimate interfacial contact between the 1D Cd S nanorods and 1T-phase dominated 2D WS_(2) nanosheets facilitates charge carrier transport,which is beneficial for achieving superior hydrogen evolution.展开更多
A non-liquid crystal compound （4-POXD-6） containing the 1,3,4-oxadiazole group and pyridyl （py） group was synthesized. And a series of supramolecular mesogenic complexes were obtained by mixing 4-POXD-6 and 4-alko...A non-liquid crystal compound （4-POXD-6） containing the 1,3,4-oxadiazole group and pyridyl （py） group was synthesized. And a series of supramolecular mesogenic complexes were obtained by mixing 4-POXD-6 and 4-alkoxybenzoic acids （Cn, n=6, 8, 12）. The liquid crystalline properties of4-POXD-6/Cn （n=6, 8, 12） were in- vestigated by means of differential scanning calorimetry, polarized optical microscopy, and wide-angle X-ray dif- fraction. It was found that 4-POXD-6/Cn （6, 8） display monotropic nematic and smectic A phases, while 4-POXD-6/C12 exhibits a SmX phase in the heating process and a SmA phase in the cooling run. Vari- able-temperature FTIR spectroscopic studies revealed hydrogen bonds existed in both crystalline and liquid crystal- line phases.展开更多
文摘Converting sustainable solar energy into hydrogen energy over semiconductor-based photocatalytic materials provides an alternative to fossil fuel consumption.However,efficient photocatalytic splitting of water to realize carbon-free hydrogen production remains a challenge.Heterojunction photocatalysts with well-defined dimensionality and perfectly matched interfaces are promising for achieving highly efficient solar-to-hydrogen conversion.Herein,we report the fabrication of a novel type of protonated graphitic carbon nitride(PCN)/Ti3C2 MXene heterojunctions with strong interfacial interactions.As expected,the two-dimensional(2D)PCN/2D Ti3C2 MXene interface heterojunction achieves a highly improved hydrogen evolution rate(2181μmol∙g‒1)in comparison with bulk g-C3N4(393μmol∙g‒1)and protonated g-C3N4(816μmol∙g‒1).The charge-regulated surfaces of PCN and the accelerated charge transport at the face-to-face 2D/2D Schottky heterojunction interface are the major contributors to the excellent hydrogen evolution performance of the composite photocatalyst.
文摘Solar-powered photocatalytic hydrogen production from water using semiconductors provides an eco-friendly and promising approach for converting solar energy into hydrogen fuel.Bulk semiconductors generally suffer from certain limitations,such as poor visible-light utilization,rapid recombination of charge carriers,and low catalytic capability.The key challenge is to develop visible-light-driven heterojunction photocatalysts that are stable and highly active during the water splitting process.Here,we demonstrate the integration of one-dimensional(1D)Cd S nanorods with two-dimensional(2D)1 T-phase dominated WS_(2) nanosheets for constructing mixed-dimensional heterojunctions for the photocatalytic hydrogen evolution reaction(HER).The resulting 1D CdS/2D WS_(2) nanoheterojunction exhibited an ultrahigh hydrogen-evolution activity of~70 mmol·g^(-1)·h^(-1) that was visible to the naked eye,as well as long-term stability under visible light illumination.The results reveal that the synergy of hybrid nanoarchitectures and intimate interfacial contact between the 1D Cd S nanorods and 1T-phase dominated 2D WS_(2) nanosheets facilitates charge carrier transport,which is beneficial for achieving superior hydrogen evolution.
文摘A non-liquid crystal compound （4-POXD-6） containing the 1,3,4-oxadiazole group and pyridyl （py） group was synthesized. And a series of supramolecular mesogenic complexes were obtained by mixing 4-POXD-6 and 4-alkoxybenzoic acids （Cn, n=6, 8, 12）. The liquid crystalline properties of4-POXD-6/Cn （n=6, 8, 12） were in- vestigated by means of differential scanning calorimetry, polarized optical microscopy, and wide-angle X-ray dif- fraction. It was found that 4-POXD-6/Cn （6, 8） display monotropic nematic and smectic A phases, while 4-POXD-6/C12 exhibits a SmX phase in the heating process and a SmA phase in the cooling run. Vari- able-temperature FTIR spectroscopic studies revealed hydrogen bonds existed in both crystalline and liquid crystal- line phases.
基金financially supported by the National Natural Science Foundation of China(22005149,21975129,and 22172077)the Natural Science Foundation of Jiangsu Province(BK20200777 and BK20211573)+1 种基金the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province,China(20KJB430034)the Science Fund for Distinguished Young Scholars,Nanjing Forestry University(JC2019002)。
