A heterojunction photocatalyst based on porous tubular g-C3N4 decorated with CdS nanoparticles was fabricated by a facile hydrothermal co-deposition method.The one-dimensional porous structure of g-C3N4 provides a hig...A heterojunction photocatalyst based on porous tubular g-C3N4 decorated with CdS nanoparticles was fabricated by a facile hydrothermal co-deposition method.The one-dimensional porous structure of g-C3N4 provides a higher specific surface area,enhanced light absorption,and better separation and transport performance of charge carriers along the longitudinal direction,all of which synergistically contribute to the superior photocatalytic activity observed.The significantly enhanced catalytic efficiency is also a benefit originating from the fast transfer of photogenerated electrons and holes between g-C3N4 and CdS through a built-in electric field,which was confirmed by investigating the morphology,structure,optical properties,electrochemical properties,and photocatalytic activities.Photocatalytic degradation of rhodamine B(RhB)and photocatalytic hydrogen evolution reaction were also carried out to investigate its photocatalytic performance.RhB can be degraded completely within 60 min,and the optimum H2 evolution rate of tubular g-C3N4/CdS composite is as high as 71.6μmol h^–1,which is about 16.3 times higher than that of pure bulk g-C3N4.The as-prepared nanostructure would be suitable for treating environmental pollutants as well as for water splitting.展开更多
Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil i...Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water. Subsequently, g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C_3N_4 was successfully decorated on the TNTAs and the g-C_3N_4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.展开更多
Recently, the g-C3N4-based heterojunctions have been widely investigated for their greatly enhanced photogenerated carrier separation efficiency. However, most studies are based on the study of g-C3N4 powders. In this...Recently, the g-C3N4-based heterojunctions have been widely investigated for their greatly enhanced photogenerated carrier separation efficiency. However, most studies are based on the study of g-C3N4 powders. In this study, a novel TiN/C3N4/CdS nanotube arrays core/shell structure is designed to improve the photoelectrochemical catalytic performance of the g-C3N4-based heterojunctions. Among them, TiN nanotube arrays do not respond to simulated solar light, and thus only serve as an excellently conductive nanotube arrays backbone for supporting g-C3N4/CdS heterojunctions. g-C3N4 prepared by simple liquid atomic layer deposition, which possesses appropriate energy band position, mainly acts as the electron acceptor to transport and separate electrons. Deposited CdS quantum dots obtained by successive ionic layer adsorption reaction can effectively absorb visible light and thus act as a light absorber. The TiN/C3N4/CdS nanotube arrays core/shell structure could be verified by X-ray diffractions, Raman spectra, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy elemental mappings and X-ray photoelectron spectroscopy. Compared with TiN/C3N4 nanotube arrays, the TiN/C3N4/CdS samples greatly improve the photoelectrochemical performance, which can be evaluated by photoelectrochemical tests and photoelectrochemical catalytic degradation. Especially, the optimized photocurrent density of TiN/C3N4/CdS has almost 120 times improvement on TiN/C3N4 at 0 V bias under simulated sunlight, which can be ascribed to the effective expansion of the light absorption range and separation of electron-hole pairs.展开更多
Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and ...Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and CH_4) by the bilayer porous graphitic carbon nitride(g-C_3 N_4) membrane. Theoretically, the bilayer g-C3 N4 membrane with a diameter of about3.25 A? should be a perfect candidate for H_2 purification from these mixed gases, which is verified by the high selectivity(S) for H_2 over other kinds of gases(3.43 × 1028 for H_2/N2; 1.40 × 1028 for H_262/H_2 O; 1.60 × 10 for H_2/CO; 4.30 × 10^(14) for H_2/Cl_2; 2.50 × 10^(55) for H_2/CH_4), and the permeance(P) of H_2(13 mol/m^2·s·Pa) across the bilayer g-C_3 N_4 membrane at 300 K, which should be of great potential in energy and environmental research. Our studies highlight a new approach towards the final goal of high P and high S molecular-sieving membranes used in simple structural engineering.展开更多
A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used ...A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used to characterize structure of hybrid MOC-16/g-C3N4, as well as UV-vis absorption spectrum and X-ray photoelectron spectroscopy were carried out to unveil photocatalytic mechanism. With the introduction of MOC-16, the absorption edge of MOC-16/g-C3N4 in UV-vis spectrum extended apparently to long-wavelength region compared with pristine g-C3N4. H2 evolution yielded with MOC-16/g-C3N4 in aqueous solution containing TEOA was much higher than that with RuL3/g-C3N4, Pd/RuL3/g-C3N4 and mixture of MOC-16 and g-C3N4, showing that the octahedral cage structure with high-efficient electron transfer and the interface interaction between MOC-16 and g-C3N4 were significant for improvement of H2 evolution.展开更多
基金support from the National Natural Science Foundation of China(51602297 and U1510109)Major Research Project of Shandong Province(2016ZDJS11A04)+3 种基金Fundamental Research Funds for the Central Universities(201612007)Postdoctoral Innovation Program of Shandong Province(201603043)Australia Research Council(ARC)under the Project DP160104089Start-up Foundation for Advanced Talents of Qingdao University of Science and Technology(010022919)~~
文摘A heterojunction photocatalyst based on porous tubular g-C3N4 decorated with CdS nanoparticles was fabricated by a facile hydrothermal co-deposition method.The one-dimensional porous structure of g-C3N4 provides a higher specific surface area,enhanced light absorption,and better separation and transport performance of charge carriers along the longitudinal direction,all of which synergistically contribute to the superior photocatalytic activity observed.The significantly enhanced catalytic efficiency is also a benefit originating from the fast transfer of photogenerated electrons and holes between g-C3N4 and CdS through a built-in electric field,which was confirmed by investigating the morphology,structure,optical properties,electrochemical properties,and photocatalytic activities.Photocatalytic degradation of rhodamine B(RhB)and photocatalytic hydrogen evolution reaction were also carried out to investigate its photocatalytic performance.RhB can be degraded completely within 60 min,and the optimum H2 evolution rate of tubular g-C3N4/CdS composite is as high as 71.6μmol h^–1,which is about 16.3 times higher than that of pure bulk g-C3N4.The as-prepared nanostructure would be suitable for treating environmental pollutants as well as for water splitting.
基金financial support from the National Natural Science Foundation of China (Nos. 51702025, 51574047)Natural Science Foundation of Jiangsu Province (Nos. BK20160277, BK20150259)
文摘Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water. Subsequently, g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C_3N_4 was successfully decorated on the TNTAs and the g-C_3N_4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications.
文摘Recently, the g-C3N4-based heterojunctions have been widely investigated for their greatly enhanced photogenerated carrier separation efficiency. However, most studies are based on the study of g-C3N4 powders. In this study, a novel TiN/C3N4/CdS nanotube arrays core/shell structure is designed to improve the photoelectrochemical catalytic performance of the g-C3N4-based heterojunctions. Among them, TiN nanotube arrays do not respond to simulated solar light, and thus only serve as an excellently conductive nanotube arrays backbone for supporting g-C3N4/CdS heterojunctions. g-C3N4 prepared by simple liquid atomic layer deposition, which possesses appropriate energy band position, mainly acts as the electron acceptor to transport and separate electrons. Deposited CdS quantum dots obtained by successive ionic layer adsorption reaction can effectively absorb visible light and thus act as a light absorber. The TiN/C3N4/CdS nanotube arrays core/shell structure could be verified by X-ray diffractions, Raman spectra, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy elemental mappings and X-ray photoelectron spectroscopy. Compared with TiN/C3N4 nanotube arrays, the TiN/C3N4/CdS samples greatly improve the photoelectrochemical performance, which can be evaluated by photoelectrochemical tests and photoelectrochemical catalytic degradation. Especially, the optimized photocurrent density of TiN/C3N4/CdS has almost 120 times improvement on TiN/C3N4 at 0 V bias under simulated sunlight, which can be ascribed to the effective expansion of the light absorption range and separation of electron-hole pairs.
基金Project supported by the Fundamental Research Funds for the Central Universities,China(Grant No.2018B19414)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161501)+5 种基金the Six Talent Peaks Project in Jiangsu Province,China(Grant No.2015-XCL-010)the National Natural Science Foundation of China(Grant Nos.51776094 and 51406075)the Program of Henan Provincial Department of Education,China(Grant No.16A330004)the Special Fund of Nanyang Normal University,China(Grant No.ZX2016003)the Science and Technology Program of Henan Department of Science and Technology,China(Grant No.182102310609)the Scientific Research and Service Platform Fund of Henan Province,China(Grant No.2016151)
文摘Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and CH_4) by the bilayer porous graphitic carbon nitride(g-C_3 N_4) membrane. Theoretically, the bilayer g-C3 N4 membrane with a diameter of about3.25 A? should be a perfect candidate for H_2 purification from these mixed gases, which is verified by the high selectivity(S) for H_2 over other kinds of gases(3.43 × 1028 for H_2/N2; 1.40 × 1028 for H_262/H_2 O; 1.60 × 10 for H_2/CO; 4.30 × 10^(14) for H_2/Cl_2; 2.50 × 10^(55) for H_2/CH_4), and the permeance(P) of H_2(13 mol/m^2·s·Pa) across the bilayer g-C_3 N_4 membrane at 300 K, which should be of great potential in energy and environmental research. Our studies highlight a new approach towards the final goal of high P and high S molecular-sieving membranes used in simple structural engineering.
基金supported by the National Natural Science Foundation of China(21875293,21821003,21890380,21720102007,21572280)the Natural Science Foundation of Guangdong Province(2016A030313268)+2 种基金the STP Project of Guangzhou(201804010386,201707010114)the Fundamental Research Funds for the Central Universities(17lgzd18,17lgzd01)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province~~
文摘A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used to characterize structure of hybrid MOC-16/g-C3N4, as well as UV-vis absorption spectrum and X-ray photoelectron spectroscopy were carried out to unveil photocatalytic mechanism. With the introduction of MOC-16, the absorption edge of MOC-16/g-C3N4 in UV-vis spectrum extended apparently to long-wavelength region compared with pristine g-C3N4. H2 evolution yielded with MOC-16/g-C3N4 in aqueous solution containing TEOA was much higher than that with RuL3/g-C3N4, Pd/RuL3/g-C3N4 and mixture of MOC-16 and g-C3N4, showing that the octahedral cage structure with high-efficient electron transfer and the interface interaction between MOC-16 and g-C3N4 were significant for improvement of H2 evolution.
