Template-Free Synthesis of One-Dimensional g-C3N4 Chain Nanostructures for Efficient Photocatalytic Hydrogen Evolution

The development of graphite-carbon nitride (g-C3N4) photocatalyst is of great significance for various visible utilization applications. Control the nanostructures of g-C3N4 can tailor its photocatalytic performance. In this paper, one-dimensional chain-like g-C3N4 was successfully synthesized by heat-induced polymerization of melamine which was saturated in ethylene glycol. The photocatalytic hydrogen production rate (HER) of the prepared g-C3N4 chain enhanced about 3 times than that of bulk g-C3N4, increasing from 9.6 μmolh−1 to 28.7 μmolh−1. The improved photocatalytic activity of the g-C3N4 chain was attributed to the advantages of porosity and nanostructure. The extraordinary nanopores result in an enlarged specific surface area for adsorption and the production of abundantly available channels for charge transfer. The one-dimensional chain-like structure can facilitate the exposure of internal/external active sites as many as possible, and induce the directional migration of charge carriers.

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Comparison in thermal stability and catalytic performance of H4PMo11VO40 heteropolyacid supported on mesoporous and macroporous silica materials

Journal of Chemical Research ◽

10.1177/1747519820925997 ◽

2020 ◽

pp. 174751982092599

Author(s):

Heng Zhang ◽

Chunhao Yang ◽

Shengying Zhao ◽

Tingting Wang ◽

Wancheng Zhu

Keyword(s):

Thermal Stability ◽

Active Sites ◽

Catalytic Performance ◽

High Dispersion ◽

High Exposure ◽

Macroporous Silica ◽

One Dimensional ◽

Ordered Macroporous ◽

The One ◽

Mcm 41

Ordered mesoporous silica, SBA-15 and MCM-41, and three-dimensionally ordered macroporous SiO2 were used as the supports of H4PMo11VO40 heteropolyacid for methacrolein oxidation. The dispersion and structural evolutions of the heteropolyacid along with thermal treatment were investigated. It was found that the heteropolyacid entered the one-dimensional mesoporous channels of SBA-15 and MCM-41, and the crystallization and growth were limited, leading to high dispersion of the heteropolyacid. However, the thermal stability was decreased under high dispersion. The migration of the heteropolyacid was observed to the end of the one-dimensional channels of SBA-15 and the outer surface of MCM-41 with calcination, accompanied by the decomposition of the heteropolyacid and the formation of MoO3. In comparison, the crystallization and growth of heteropolyacid were not limited in the open macropores of three-dimensionally ordered macroporous SiO2. Dispersed particles on the surface of the macropores with size of about 5 nm exhibited a higher thermal stability. The decomposition of the heteropolyacid in the SBA-15 and MCM-41 supported catalysts resulted in the loss of strong acid sites, causing low selectivity to methacrylic acid in methacrolein oxidation. High thermal stability with high exposure of the active sites in the three-dimensionally ordered macroporous SiO2 supported catalyst contributed to the enhancement in the catalytic performance.

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Enhancement of Photocatalytic Activity under Visible Light Irradiation via the AgI@TCNQ Core-Shell Structure

Materials ◽

10.3390/ma12101679 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1679 ◽

Cited By ~ 3

Author(s):

Wanli Xie ◽

Li Liu ◽

Wenquan Cui ◽

Weijia An

Keyword(s):

Shell Structure ◽

Active Sites ◽

Photocatalytic Performance ◽

Degradation Process ◽

Charge Carriers ◽

Core Shell ◽

Transport Channel ◽

Surface Active ◽

Core Shell Structure ◽

Unique Core

In this paper, a AgI@TCNQ photocatalyst with a core-shell structure was reported. A two-dimensional TCNQ (7,7,8,8-Tetracyanoquinodimethane) nanosheet, with a π-π conjugate structure, was used as a shell layer to realize the flexible coating on the surface of AgI nanoparticles. These special core-shell structure composites solve the key problems of the small interface of the bulk composites and the lesser charge transfer paths, which could accelerate the migration of photogenerated carriers. Thus, the AgI@TCNQ photocatalysts showed the better photodegradation performance for the methylene blue (MB) solution, and the degradation rate of AgI@TCNQ (1 wt.%) composite was 1.8 times than AgI under irradiation. The reactive species trapping experiments demonstrated that ·O2−, h+, and ·OH all participated in the MB degradation process. The photocatalytic mechanism of AgI@TCNQ composites could be rationally explained by considering the Z-scheme structure, resulting in a higher redox potential and more efficient separation of charge carriers. At the same time, the unique core-shell structure provides a larger contact area, expands the charge transport channel, and increases the surface active sites, which are beneficial for improving photocatalytic performance.

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Electrochemical Synthesis and Structural Characterization of the One-Dimensional Chain Compound (Et4N)2[As2Te5] and the Tellurido Arsenate (Me4N)4[As4Te6].cntdot.2en

Chemistry of Materials ◽

10.1021/cm00042a013 ◽

1994 ◽

Vol 6 (6) ◽

pp. 780-783 ◽

Cited By ~ 19

Author(s):

Christopher J. Warren ◽

Robert C. Haushalter ◽

Andrew B. Bocarsly

Keyword(s):

Structural Characterization ◽

Electrochemical Synthesis ◽

Dimensional Chain ◽

One Dimensional ◽

The One ◽

Chain Compound

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q-Deformed Anisotropic Superexchange Interaction, Frustration and GLpq(2)

Modern Physics Letters B ◽

10.1142/s0217984998000986 ◽

1998 ◽

Vol 12 (21) ◽

pp. 859-866 ◽

Cited By ~ 1

Author(s):

S. Grillo ◽

H. Montani

Keyword(s):

Boundary Condition ◽

Quantum Group ◽

Group Structure ◽

Superexchange Interaction ◽

Dimensional Chain ◽

Interaction Theory ◽

Standard Quantum ◽

One Dimensional ◽

Local Rotation ◽

The One

We study a suitable q-deformed version of the Moriya's superexchange interaction theory by means of its underlying quantum group structure. We show that the one-dimensional chain case is associated with the non-standard quantum group GL pq(2), evidencing the integrability structure of the system. This biparametric deformation of GL(2; C) arise as a twisting of GL q(2) and it match exactly the local rotation appearing in the Shekhtman's work.1 This allow us to express the frustration condition in terms of this twisting, also showing that effect of the Moriya's vector amounts to a twisting of the boundary condition.

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A one-dimensional cobalt(II) coordination polymer based on 2,4′-oxydibenzoic acid: poly[[[diaquabis[2-(4-carboxyphenoxy)benzoato-κO1]cobalt(II)]-μ-4,4′-bipyridine-κ2N:N′] dihydrate]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614012066 ◽

2014 ◽

Vol 70 (7) ◽

pp. 654-658 ◽

Cited By ~ 1

Author(s):

Long Tang ◽

Feng Fu ◽

Ji-Jiang Wang ◽

Qi-Rui Liu ◽

Hang-Hang Zhao

Keyword(s):

Coordination Polymer ◽

Hydrothermal Condition ◽

Dimensional Chain ◽

Supramolecular Architecture ◽

Two Dimensional ◽

X Ray Diffraction ◽

One Dimensional ◽

X Ray ◽

The One ◽

Two Sides

The reaction of CoSO4with 2,4-oxydibenzoic acid (H2oba) and 4,4′-bipyridine (bipy) under hydrothermal condition yielded a new one-dimensional cobalt(II) coordination polymer, {[Co(C14H9O5)2(C10H8N2)(H2O)2]·2H2O}n, which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, magnetic properties and single-crystal X-ray diffraction. The CoIIions are connected by bipy ligands into infinite one-dimensional chains. The Hoba−ligands extend out from the two sides of the one-dimensional chain. O—H...O hydrogen bonding extends these chains into a two-dimensional supramolecular architecture.

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