Insights into the in-built Tb4+/Tb3+ redox centers for boosted hydroxyl radical yield and superior separation of charge carriers by investigating Tb2O3/g-C3N4 composite photocatalysts

Conductive polymers have been widely investigated in various applications. Several conductive polymers, such as polyaniline (PANI), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT)), and polythiophene (PTh) have been loaded with various semiconductor nanomaterials to prepare the composite photocatalysts. However, a critical review of conductive polymer-based composite photocatalysts has not been available yet. Therefore, in this review, we summarized the applications of conductive polymers in the preparation of composite photocatalysts for photocatalytic degradation of hazardous chemicals, antibacterial, and photocatalytic hydrogen production. Various materials were systematically surveyed to illustrate their preparation methods, morphologies, and photocatalytic performances. The synergic effect between conductive polymers and semiconductor nanomaterials were observed for a lot of composite photocatalysts. The band structures of the composite photocatalysts can be analyzed to explain the mechanism of their enhanced photocatalytic activity. The incorporation of conductive polymers can result in significantly improved visible-light driven photocatalytic activity by enhancing the separation of photoexcited charge carriers, extending the light absorption range, increasing the adsorption of reactants, inhibiting photo-corrosion, and reducing the formation of large aggregates. This review provides a systematic concept about how conductive polymers can improve the performance of composite photocatalysts.

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Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.31 ◽

2020 ◽

Vol 11 ◽

pp. 407-416 ◽

Cited By ~ 3

Author(s):

Changqiang Yu ◽

Min Wen ◽

Zhen Tong ◽

Shuhua Li ◽

Yanhong Yin ◽

...

Keyword(s):

Photocatalytic Activity ◽

Organic Contaminants ◽

Hydrothermal Process ◽

Charge Carriers ◽

Molecular Vibration ◽

Surface Element ◽

Composite Photocatalysts ◽

Excellent Photocatalytic Activity ◽

Photoinduced Charge ◽

Facile Hydrothermal Process

Photocatalysis is considered to be a green and promising technology for transforming organic contaminants into nontoxic products. In this work, a CuO/tourmaline composite with zero-dimensional/two-dimensional (0D/2D) CuO architecture was successfully obtained via a facile hydrothermal process, and its photocatalytic activity was evaluated by the degradation of methylene blue (MB). Surface element valence state and molecular vibration characterization revealed that CuO chemically interacted with tourmaline via Si–O–Cu bonds. The specific surface area of the CuO/tourmaline composite (23.60 m2 g−1) was larger than that of the pristine CuO sample (3.41 m2 g−1). The CuO/tourmaline composite exhibited excellent photocatalytic activity for the degradation of MB, which was ascribed to the increase in the quantity of the adsorption-photoreactive sites and the efficient utilization of the photoinduced charge carriers. This study provides a facile strategy for the construction of 0D/2D CuO structures and the design of tourmaline-based functional composite photocatalysts for the treatment of organic contaminants in water.

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A polar mineral tourmaline enables synthesis of 0D/2D CuO photocatalyst with enhanced photocatalytic activity

10.3762/bxiv.2020.2.v1 ◽

2020 ◽

Author(s):

Changqiang Yu ◽

Min Wen ◽

Zhen Tong ◽

Shuhua Li ◽

Yanhong Yin ◽

...

Keyword(s):

Organic Contaminants ◽

Superoxide Radical ◽

Aqueous Suspension ◽

Hydrothermal Process ◽

Charge Carriers ◽

Two Dimensional ◽

Efficient Utilization ◽

Composite Photocatalysts ◽

Photoinduced Charge ◽

Facile Hydrothermal Process

Photocatalysis is considered to be a green and promising technology for transforming organic contaminants into nontoxic products. In this work, the CuO/tourmaline composite with zero-dimensional/two-dimensional (0D/2D) CuO architecture was obtained via a facile hydrothermal process. CuO chemically interacted with tourmaline via Si-O-Cu bond. The specific surface area of the CuO/tourmaline composite (23.60 m2 g-1) was larger than that of pristine CuO (3.41 m2 g-1). Three predominant reactive species of superoxide radical (O2 •-), hydroxyl radical (•OH), and h+ were generated by the CuO/tourmaline composite aqueous suspension system under light irradiation. The CuO/tourmaline composite exhibited excellent photocatalytic capacity for the decomposition of organic pollutants, which was ascribed to the increase in the quantity of adsorption-photoreactive sites and the efficient utilization of photoinduced charge carriers benefited from tourmaline. This study offered a facile strategy for the construction of 0D/2D CuO structure and the design of tourmaline-based functional composite photocatalysts for the treatment of organic contaminants in waster.

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Radical Formation in Ozone Reactions with Lignin and Carbohydrate Model Compounds

Holzforschung ◽

10.1515/hf.1999.049 ◽

1999 ◽

Vol 53 (3) ◽

pp. 292-298 ◽

Cited By ~ 36

Author(s):

M. Ragnar ◽

T. Eriksson ◽

T. Reitberger

Keyword(s):

Hydroxyl Radical ◽

Metal Ions ◽

Ph Dependence ◽

Model Compounds ◽

Lignin Model Compounds ◽

Lignin Model ◽

Kinetics Of ◽

Radical Yield ◽

Ozone Reactions ◽

Ozone Bleaching

Summary Using different independent methods, the kinetics of ozone consumption and the initial radical yield in reactions of ozone with lignin and carbohydrate model compounds were investigated. It was demonstrated that ozone reacts with phenolates several orders of magnitude more rapidly than with corresponding undissociated phenols. The pH dependence of the radical yield does not completely follow the pK a-value of the phenols. In fact, the radical yield starts to increase at pH 3 for all the phenolic model compounds investigated. Several indications suggest that superoxide rather than the hydroxyl radical is initially formed when ozone reacts with lignin model compounds. In contrast to lignin model compounds no radicals were detected in ozone reactions with carbohydrate model compounds or olefins. On the basis of this study, it may be concluded that ozone bleaching should preferably be performed at pH 3 and at a higher consistency. No significant effect of metal ions was observed.

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Advances in materials engineering of CdS coupled with dual cocatalysts of graphene and MoS2 for photocatalytic hydrogen evolution

Pure and Applied Chemistry ◽

10.1515/pac-2018-0507 ◽

2018 ◽

Vol 90 (9) ◽

pp. 1379-1392 ◽

Cited By ~ 2

Author(s):

Nan Zhang ◽

Shao-Hai Li ◽

Xianzhi Fu ◽

Yi-Jun Xu

Keyword(s):

Hydrogen Evolution ◽

Rational Design ◽

Light Response ◽

Charge Carriers ◽

Main Attention ◽

Electrically Conductive ◽

Ternary Composite ◽

Materials Engineering ◽

Visible Light Response ◽

Composite Photocatalysts

Abstract Photocatalytic water splitting for hydrogen evolution as an attractive strategy for developing sustainable energy by utilizing sunlight has attracted enormous research efforts. Cadmium sulfide (CdS) with visible light response and proper energy band structure has been studied intensively. To suppress the recombination of charge carriers and facilitate the hydrogen evolution reaction (HER) over CdS, electrically conductive graphene and active-site-abundant MoS2 have proven to be efficient dual cocatalysts to improve the photocatalytic HER performance of CdS. In this review, we will focus on the representative ternary composite photocatalysts of CdS-graphene-MoS2. The synthesis approaches are first summarized, followed by the discussion of the roles of each component in the composites. Then main attention will be paid to highlighting the effects of the microscopic structures of the components on the photocatalytic performance of the composites for HER applications. It is expected that this review could be helpful to the rational design and further optimization of semiconductor-based composite photocatalysts through materials engineering strategies for solar energy conversion.

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Analysis of the Influencing Factors of the Hydroxyl Radical Yield in a Hydrodynamic Cavitation Bubble of a Chitosan Solution Based on a Numerical Simulation

ACS Omega ◽

10.1021/acsomega.0c05335 ◽

2021 ◽

Vol 6 (5) ◽

pp. 3736-3744

Author(s):

Xiangyu Zhang ◽

Xinfeng Zhu ◽

Yan Cao ◽

Kunming Zhang ◽

Yongchun Huang ◽

...

Keyword(s):

Numerical Simulation ◽

Hydroxyl Radical ◽

Influencing Factors ◽

Cavitation Bubble ◽

Chitosan Solution ◽

Hydrodynamic Cavitation ◽

Radical Yield

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LAYERED BISMUTH TUNGSTATE – HETEROGENEOUS PHOTOCATALYSIS FOR ENVIRONMENTAL REMEDIATION

CHEMISTRY AND CHEMICAL ENGINEERING ◽

10.51348/rltw5118 ◽

2021 ◽

pp. 3-11

Keyword(s):

Environmental Remediation ◽

Light Response ◽

Environmental Issues ◽

Modern Society ◽

Heterogeneous Photocatalysis ◽

Charge Carriers ◽

Layered Compounds ◽

Full Potential ◽

Composite Photocatalysts ◽

Layered Perovskites

Air and water pollution has been one of the challenging environmental issues in modern society. Since the Honda-Fujishima effect was first reported in 1972, a semiconductor-based photocatalysis has been regarded as one of the most green and economical processes for potential application in environmental remediation. Bismuth-based semiconductors are regarded as a promising group of advanced photocatalytic materials due to their suitable band gap for visible light response, an increased mobility of photo-generated charge carriers because of well-dispersed Bi 6s orbital, non-toxicity, and easy tailoring of their morphologies. To utilize its full potential in environmental remediation, various studies have been carried out to enhance the photocatalytic performance of layered Bi2WO6, one of the simplest members of the Aurivillius oxide family of layered perovskites. This review introduces past achievements, the state of the art, and future perspectives in heterogeneous photocatalysis and its application in environmental remediation, particularly in photocatalytic air and water purification. The layered compounds, bismuth-based photocatalysts, and composite photocatalysts and their application in environmental remediation are discussed.

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