The Experts below are selected from a list of 27096 Experts worldwide ranked by ideXlab platform
Markus Antonietti - One of the best experts on this subject based on the ideXlab platform.
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Graphitic Carbon Nitride “Reloaded” Emerging Applications Beyond (Photo)Catalysis
ChemInform, 2016Co-Authors: Jian Liu, Hongqiang Wang, Markus AntoniettiAbstract:Review: renaissance of Graphitic Carbon nitride (g-C3N4) as a highly active photo/electrocatalyst, and diverse applications of the metal-free polymer; 94 refs.
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triazine based Graphitic Carbon nitride a two dimensional semiconductor
Angewandte Chemie, 2014Co-Authors: Gerardo Algarasiller, Markus Antonietti, Nikolai Severin, Samantha Y. Chong, Torbjörn Björkman, Robert G. Palgrave, Andrea Laybourn, Yaroslav Z. Khimyak, Arkady V. Krasheninnikov, Jürgen P. RabeAbstract:Graphitic Carbon nitride has been predicted to be structurally analogous to Carbon-only graphite, yet with an inherent bandgap. We have grown, for the first time, macroscopically large crystalline thin films of triazine-based, Graphitic Carbon nitride (TGCN) using an ionothermal, interfacial reaction starting with the abundant monomer dicyandiamide. The films consist of stacked, two-dimensional (2D) crystals between a few and several hundreds of atomic layers in thickness. Scanning force and transmission electron microscopy show long-range, in-plane order, while optical spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations corroborate a direct bandgap between 1.6 and 2.0 eV. Thus TGCN is of interest for electronic devices, such as field-effect transistors and light-emitting diodes.
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Triazine‐Based Graphitic Carbon Nitride: a Two‐Dimensional Semiconductor
Angewandte Chemie (International ed. in English), 2014Co-Authors: Gerardo Algara-siller, Markus Antonietti, Nikolai Severin, Samantha Y. Chong, Torbjörn Björkman, Robert G. Palgrave, Andrea Laybourn, Yaroslav Z. Khimyak, Arkady V. Krasheninnikov, Jürgen P. RabeAbstract:Graphitic Carbon nitride has been predicted to be structurally analogous to Carbon-only graphite, yet with an inherent bandgap. We have grown, for the first time, macroscopically large crystalline thin films of triazine-based, Graphitic Carbon nitride (TGCN) using an ionothermal, interfacial reaction starting with the abundant monomer dicyandiamide. The films consist of stacked, two-dimensional (2D) crystals between a few and several hundreds of atomic layers in thickness. Scanning force and transmission electron microscopy show long-range, in-plane order, while optical spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations corroborate a direct bandgap between 1.6 and 2.0 eV. Thus TGCN is of interest for electronic devices, such as field-effect transistors and light-emitting diodes.
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polymeric Graphitic Carbon nitride for heterogeneous photocatalysis
ACS Catalysis, 2012Co-Authors: Xinchen Wang, Siegfried Blechert, Markus AntoniettiAbstract:Polymeric Graphitic Carbon nitride (for simplicity, g-C3N4) is a layered material similar to graphene, being composed of only C, N, and some impurity H. Contrary to graphenes, g-C3N4 is a medium band gap semiconductor and an effective photocatalyst for a broad variety of reactions, and it possesses a high thermal and chemical stability In this Perspective, we describe the polycondensation of this structure, how to modify band positions and band gap by doping and copolymerization, and how to texture the organic solid to make it an effective photocatalyst. We then describe the photochemical splitting of water and some mild and selective photooxidation reactions catalyzed by g-C3N4.
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ionothermal synthesis of crystalline condensed Graphitic Carbon nitride
Chemistry: A European Journal, 2008Co-Authors: Michael J Bojdys, Markus Antonietti, Jens Muller, Arne ThomasAbstract:Herein we report the synthesis of a crystalline Graphitic Carbon nitride, or g-C(3)N(4), obtained from the temperature-induced condensation of dicyandiamide (NH(2)C(=NH)NHCN) by using a salt melt of lithium chloride and potassium chloride as the solvent. The proposed crystal structure of this g-C(3)N(4) species is based on sheets of hexagonally arranged s-heptazine (C(6)N(7)) units that are held together by covalent bonds between C and N atoms which are stacked in a Graphitic, staggered fashion, as corroborated by powder X-ray diffractometry and high-resolution transmission electron microscopy.
Jürgen P. Rabe - One of the best experts on this subject based on the ideXlab platform.
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triazine based Graphitic Carbon nitride a two dimensional semiconductor
Angewandte Chemie, 2014Co-Authors: Gerardo Algarasiller, Markus Antonietti, Nikolai Severin, Samantha Y. Chong, Torbjörn Björkman, Robert G. Palgrave, Andrea Laybourn, Yaroslav Z. Khimyak, Arkady V. Krasheninnikov, Jürgen P. RabeAbstract:Graphitic Carbon nitride has been predicted to be structurally analogous to Carbon-only graphite, yet with an inherent bandgap. We have grown, for the first time, macroscopically large crystalline thin films of triazine-based, Graphitic Carbon nitride (TGCN) using an ionothermal, interfacial reaction starting with the abundant monomer dicyandiamide. The films consist of stacked, two-dimensional (2D) crystals between a few and several hundreds of atomic layers in thickness. Scanning force and transmission electron microscopy show long-range, in-plane order, while optical spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations corroborate a direct bandgap between 1.6 and 2.0 eV. Thus TGCN is of interest for electronic devices, such as field-effect transistors and light-emitting diodes.
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Triazine‐Based Graphitic Carbon Nitride: a Two‐Dimensional Semiconductor
Angewandte Chemie (International ed. in English), 2014Co-Authors: Gerardo Algara-siller, Markus Antonietti, Nikolai Severin, Samantha Y. Chong, Torbjörn Björkman, Robert G. Palgrave, Andrea Laybourn, Yaroslav Z. Khimyak, Arkady V. Krasheninnikov, Jürgen P. RabeAbstract:Graphitic Carbon nitride has been predicted to be structurally analogous to Carbon-only graphite, yet with an inherent bandgap. We have grown, for the first time, macroscopically large crystalline thin films of triazine-based, Graphitic Carbon nitride (TGCN) using an ionothermal, interfacial reaction starting with the abundant monomer dicyandiamide. The films consist of stacked, two-dimensional (2D) crystals between a few and several hundreds of atomic layers in thickness. Scanning force and transmission electron microscopy show long-range, in-plane order, while optical spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations corroborate a direct bandgap between 1.6 and 2.0 eV. Thus TGCN is of interest for electronic devices, such as field-effect transistors and light-emitting diodes.
Xinchen Wang - One of the best experts on this subject based on the ideXlab platform.
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Graphitic Carbon nitride polymers toward sustainable photoredox catalysis
Angewandte Chemie, 2015Co-Authors: Yun Zheng, Bo Wang, Xinchen WangAbstract:: As a promising two-dimensional conjugated polymer, Graphitic Carbon nitride (g-C3 N4 ) has been utilized as a low-cost, robust, metal-free, and visible-light-active photocatalyst in the field of solar energy conversion. This Review mainly describes the latest advances in g-C3 N4 photocatalysts for water splitting. Their application in CO2 conversion, organosynthesis, and environmental purification is also briefly discussed. The methods to modify the electronic structure, nanostructure, crystal structure, and heterostructure of g-C3 N4 , together with correlations between its structure and performance are illustrated. Perspectives on the challenges and opportunities for the future exploration of g-C3 N4 photocatalysts are provided. This Review will promote the utilization of g-C3 N4 materials in the fields of photocatalysis, energy conversion, environmental remediation, and sensors.
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Helical Graphitic Carbon nitrides with photocatalytic and optical activities
Angewandte Chemie (International ed. in English), 2014Co-Authors: Yun Zheng, Lihua Lin, Fangsong Guo, Xinchen WangAbstract:Graphitic Carbon nitride can be imprinted with a twisted hexagonal rod-like morphology by a nanocasting technique using chiral silicon dioxides as templates. The helical nanoarchitectures promote charge separation and mass transfer of Carbon nitride semiconductors, enabling it to act as a more efficient photocatalyst for water splitting and CO2 reduction than the pristine Carbon nitride polymer. This is to our knowledge a unique example of chiral Graphitic Carbon nitride that features both left- and right-handed helical nanostructures and exhibits unique optical activity to circularly polarized light at the semiconductor absorption edge as well as photoredox activity for solar-to-chemical conversion. Such helical nanostructured polymeric semiconductors are envisaged to hold great promise for a range of applications that rely on such semiconductor properties as well as chirality for photocatalysis, asymmetric catalysis, chiral recognition, nanotechnology, and chemical sensing.
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photochemical reduction of co2 by Graphitic Carbon nitride polymers
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Jinliang Lin, Zhiming Pan, Xinchen WangAbstract:The combination of cobalt redox catalysis and Carbon nitride photocatalysis to construct a cascade photoreaction system has been developed for the deoxygenative reduction of CO2 to CO with visible light. The Graphitic Carbon nitride has been demonstrated to function both as a capture/activation substrate of CO2 and a photocatalyst, whereas the introduced cobalt species act as reductive and oxidative promoters to accelerate charge-carrier separation and transfer kinetics. This hybrid photosystem contains inexpensive substances that synergetically catalyze CO2-to-CO conversion at mild conditions, with a high stability of catalysts. The optimization in the surface and texture structures as well as reaction conditions has been demonstrated. The results represent an important step toward artificial photosynthesis by using cost-acceptable materials.
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exfoliated Graphitic Carbon nitride nanosheets as efficient catalysts for hydrogen evolution under visible light
Advanced Materials, 2013Co-Authors: Shubin Yang, Xinchen Wang, Yongji Gong, Jinshui Zhang, Liang Zhan, Zheyu Fang, Robert Vajtai, Pulickel M AjayanAbstract:Graphitic Carbon nitride nanosheets are extracted, produced via simple liquid-phase exfoliation of a layered bulk material, g-C3N4. The resulting nanosheets, having ≈2 nm thickness and N/C atomic ratio of 1.31, show an optical bandgap of 2.65 eV. The Carbon nitride nanosheets are demonstrated to exhibit excellent photocatalytic activity for hydrogen evolution under visible light.
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polymeric Graphitic Carbon nitride for heterogeneous photocatalysis
ACS Catalysis, 2012Co-Authors: Xinchen Wang, Siegfried Blechert, Markus AntoniettiAbstract:Polymeric Graphitic Carbon nitride (for simplicity, g-C3N4) is a layered material similar to graphene, being composed of only C, N, and some impurity H. Contrary to graphenes, g-C3N4 is a medium band gap semiconductor and an effective photocatalyst for a broad variety of reactions, and it possesses a high thermal and chemical stability In this Perspective, we describe the polycondensation of this structure, how to modify band positions and band gap by doping and copolymerization, and how to texture the organic solid to make it an effective photocatalyst. We then describe the photochemical splitting of water and some mild and selective photooxidation reactions catalyzed by g-C3N4.
Wei Chen - One of the best experts on this subject based on the ideXlab platform.
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self regenerated solar driven photocatalytic water splitting by urea derived Graphitic Carbon nitride with platinum nanoparticles
Chemical Communications, 2012Co-Authors: Yuewei Zhang, Luhua Lu, Guan Wu, Wei ChenAbstract:A natural self-regeneration step for urea derived Graphitic Carbon nitride with platinum nanoparticles is found by simply opening the system to air in the dark under ambient conditions, following its solar-driven hydrogen production. The produced peroxides deactivate the Graphitic Carbon nitride. Release of weakly bound peroxides on the polymeric semiconductor surface is a crucial process for regeneration.
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simple pyrolysis of urea into Graphitic Carbon nitride with recyclable adsorption and photocatalytic activity
Journal of Materials Chemistry, 2011Co-Authors: Jinghai Liu, Tiekai Zhang, Zhichao Wang, Graham Dawson, Wei ChenAbstract:Graphitic Carbon nitride (g-C3N4) was produced on a large scale by the pyrolysis of urea under ambient pressure without additive assistance. The retainable pyrolysis-generated self-supporting atmosphere and the reaction temperature are two necessary conditions. This g-C3N4 as photocatalyst shows recyclable adsorption and photocatalytic activity under visible light.
Si Zhang - One of the best experts on this subject based on the ideXlab platform.
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Recent progress on band and surface engineering of Graphitic Carbon nitride for artificial photosynthesis
Applied Surface Science, 2018Co-Authors: Muye Liu, Si ZhangAbstract:Abstract Artificial photosynthesis based on semiconductor photocatalysts has attracted great attentions recent years for its advantage in clean energy applications. Environmental friendly metal free semiconducting Graphitic Carbon nitride, which can be synthesized via simple pyrolysis of cheap industrial resources at low cost, with visible light photocatalytic activity for hydrogen evolution, oxygen evolution, hydrogen peroxide production and reduction of Carbon dioxide has been intensively studied in recent ten years. On the way of developing highly active photocatalysts, publications focusing on Graphitic Carbon nitride have been dramatically increased especially in recent five years. These researches have revealed some key issues, which includes morphology, atomic composition, basal plane structure and defects, composites and type of co-catalysts, influence photocatalytic activity of Graphitic Carbon nitride based materials from different aspects. These aspects include light absorption, charge separation/migration and surface reactions, which can be categorized into band structure and surface activity characters of Graphitic Carbon nitride based materials. This review is focusing on engineering band and surface of Graphitic Carbon nitride for artificial photosynthesis. Through reviewing the recent progress on Graphitic Carbon nitride based artificial photosynthesis researches, it may provide more comprehensive and in-depth understanding for further designing of highly activity photocatalysts based on Graphitic Carbon nitride.
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Boosting visible light photocatalytic hydrogen evolution of Graphitic Carbon nitride via enhancing it interfacial redox activity with cobalt/nitrogen doped tubular Graphitic Carbon
Applied Catalysis B: Environmental, 2018Co-Authors: Yijie Zhang, Si Zhang, Ying Chen, Jinghai Liu, Hongyun Jin, Shuen Hou, Kai Dai, Weiguo SongAbstract:Abstract Carbon based nanomaterials have attracted great attentions in the fields of electrocatalysis and photocatalysis. Here, we report our recent progress on photocatalytic hydrogen evolution of Graphitic Carbon nitride (g-C3N4) by introducing Carbon based electrocatalyst as co-catalyst. Cobalt/nitrogen doped Graphitic Carbon (Co-NG) composite with tubular structure was synthesized by cobalt catalyzed Carbonization and graphitization of urea under thermal treatment. Co-NG with strong interaction of cobalt and nitrogen doped Graphitic Carbon has shown low overpotential for electrocatalytic hydrogen evolution reaction. It was thus used as co-catalyst for Graphitic Carbon nitride (g-C3N4). Beside enhanced light absorption and reduced recombination of Co-NG/g-C3N4 heterostructure composite, high interfacial redox reaction activity of Co-NG was found. The photocatalytic hydrogen evolution activity of Co-NG/g-C3N4 was thus effectively improved.
