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Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation

[Image: see text] In this work, a series of heterostructure Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe layered double hydroxide (LDH) nanocomposites were prepared by a combination of an electrostatic self-assembly and in situ photoreduction method. In this method, positively charged p-type Ag(3)PO(4) was electro...

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Autores principales: Nayak, Susanginee, Parida, K. M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2018
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6644866/
https://www.ncbi.nlm.nih.gov/pubmed/31458892
http://dx.doi.org/10.1021/acsomega.8b00847
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author Nayak, Susanginee
Parida, K. M.
author_facet Nayak, Susanginee
Parida, K. M.
author_sort Nayak, Susanginee
collection PubMed
description [Image: see text] In this work, a series of heterostructure Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe layered double hydroxide (LDH) nanocomposites were prepared by a combination of an electrostatic self-assembly and in situ photoreduction method. In this method, positively charged p-type Ag(3)PO(4) was electrostatically bonded to the self-assembled negatively charged surface of the n–n-type g-C(3)N(4)/NiFe (CNLDH) LDH hybrid material with partial reduction of Ag(+) to metallic Ag nanoparticles (NPs) by the photogenerated electrons and available surface −OH groups of LDH under visible light irradiation. The presence of Ag(3)PO(4) as a p-type semiconductor, the surface plasmon resonance (SPR) effect of metallic Ag NPs, and oxygen vacancies as O(v)-type defects in NiFe LDH could greatly achieve the quasi-type-II p–n/n–n dual heterojunctions, which was revealed by the shifted conduction band and valence band potentials in Mott–Schottky (M–S) analysis. Among all the optimized heterostructures, CNLDHAgP4 could achieve the highest photocatalytic Cr(VI) reduction rate of 97% and phenol oxidation rate of 90% in 2 h. The heterostructure CNLDHAgP4 photocatalyst possesses a unique morphology consisting of cubic phases of both Ag NPs and Ag(3)PO(4), which adhered to the thin and curvy layers of the CNLDH hybrid for smooth electronic and ionic charge transport. Furthermore, the intimate Schottky barriers formed at the interface of quasi-type-II p–n/n–n dual heterojunctions were verified by the photoluminescence, linear sweep voltammetry, M–S, electrochemical impedance study, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy studies. The SPR effect of Ag NPs and oxygen vacancies as O(v)-type defect in NiFe LDH can effectively accelerate the threshold of charge separation and be the main reason for the enhanced activity achieved by the as-fabricated heterostructure photocatalyst.
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spelling pubmed-66448662019-08-27 Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation Nayak, Susanginee Parida, K. M. ACS Omega [Image: see text] In this work, a series of heterostructure Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe layered double hydroxide (LDH) nanocomposites were prepared by a combination of an electrostatic self-assembly and in situ photoreduction method. In this method, positively charged p-type Ag(3)PO(4) was electrostatically bonded to the self-assembled negatively charged surface of the n–n-type g-C(3)N(4)/NiFe (CNLDH) LDH hybrid material with partial reduction of Ag(+) to metallic Ag nanoparticles (NPs) by the photogenerated electrons and available surface −OH groups of LDH under visible light irradiation. The presence of Ag(3)PO(4) as a p-type semiconductor, the surface plasmon resonance (SPR) effect of metallic Ag NPs, and oxygen vacancies as O(v)-type defects in NiFe LDH could greatly achieve the quasi-type-II p–n/n–n dual heterojunctions, which was revealed by the shifted conduction band and valence band potentials in Mott–Schottky (M–S) analysis. Among all the optimized heterostructures, CNLDHAgP4 could achieve the highest photocatalytic Cr(VI) reduction rate of 97% and phenol oxidation rate of 90% in 2 h. The heterostructure CNLDHAgP4 photocatalyst possesses a unique morphology consisting of cubic phases of both Ag NPs and Ag(3)PO(4), which adhered to the thin and curvy layers of the CNLDH hybrid for smooth electronic and ionic charge transport. Furthermore, the intimate Schottky barriers formed at the interface of quasi-type-II p–n/n–n dual heterojunctions were verified by the photoluminescence, linear sweep voltammetry, M–S, electrochemical impedance study, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy studies. The SPR effect of Ag NPs and oxygen vacancies as O(v)-type defect in NiFe LDH can effectively accelerate the threshold of charge separation and be the main reason for the enhanced activity achieved by the as-fabricated heterostructure photocatalyst. American Chemical Society 2018-07-04 /pmc/articles/PMC6644866/ /pubmed/31458892 http://dx.doi.org/10.1021/acsomega.8b00847 Text en Copyright © 2018 American Chemical Society This is an open access article published under an ACS AuthorChoice License (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html) , which permits copying and redistribution of the article or any adaptations for non-commercial purposes.
spellingShingle Nayak, Susanginee
Parida, K. M.
Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title_full Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title_fullStr Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title_full_unstemmed Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title_short Dynamics of Charge-Transfer Behavior in a Plasmon-Induced Quasi-Type-II p–n/n–n Dual Heterojunction in Ag@Ag(3)PO(4)/g-C(3)N(4)/NiFe LDH Nanocomposites for Photocatalytic Cr(VI) Reduction and Phenol Oxidation
title_sort dynamics of charge-transfer behavior in a plasmon-induced quasi-type-ii p–n/n–n dual heterojunction in ag@ag(3)po(4)/g-c(3)n(4)/nife ldh nanocomposites for photocatalytic cr(vi) reduction and phenol oxidation
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6644866/
https://www.ncbi.nlm.nih.gov/pubmed/31458892
http://dx.doi.org/10.1021/acsomega.8b00847
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AT paridakm dynamicsofchargetransferbehaviorinaplasmoninducedquasitypeiipnnndualheterojunctioninagag3po4gc3n4nifeldhnanocompositesforphotocatalyticcrvireductionandphenoloxidation