Oxygen Vacant Semiconductor Photocatalysts

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(25)

Published: April 1, 2021

Abstract Semiconductor photocatalysis acts as a sustainable green technology to convert solar energy for environmental purification and production of renewable energy. However, the current photocatalysts suffer from inefficient photoabsorption, rapid recombination photogenerated electrons holes, inadequate surface reactive sites. Introduction oxygen vacancies (OVs) in has been demonstrated be an efficacious strategy solve these issues improve photocatalytic efficiency. This review systematically summarizes recent progress vacant semiconductor photocatalysts. Firstly, formation characterizations OVs are briefly introduced. Then, highlighted roles reactions three types typical oxygen‐containing semiconductors, including metal oxides (TiO 2 , ZnO, WO 3 W 18 O 49 MoO BiO 2‐x SnO etc), hydroxides (In(OH) Ln(OH) (Ln=La, Pr, Nd), Layered double hydroxides) oxysalts (bismuth‐based others) Moreover, advanced applications photocatalysts, such pollutant removal, H production, CO reduction, N fixation organic synthesis summarized. Finally, overview on challenges prospective future materials is proposed.

Language: Английский

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Exceptional Cocatalyst‐Free Photo‐Enhanced Piezocatalytic Hydrogen Evolution of Carbon Nitride Nanosheets from Strong In‐Plane Polarization

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(24)

Published: May 8, 2021

Abstract Utilizing mechanical energy to produce hydrogen is emerging as a promising way generate renewable energy, but challenged by low efficiency and scanty cognition. In this work, graphitic carbon nitride (g‐C 3 N 4 ) with an atomically thin sheet‐like structure applied for prominent piezocatalytic photo‐enhanced H 2 production. It revealed that the anomalous piezoelectricity in g‐C originates from strong in‐plane polarization along ‐axis, contributed superimposed polar tri‐s‐triazine units flexoelectric effect derived structured triangular cavities, which provides powerful electrochemical driving force water reduction reaction. Furthermore, charge transfer enables nanosheets reserve more energized charges fully participate reaction at surface reactive sites enriched strain‐induced vacancies. Without any cocatalysts, exceptional photo‐piezocatalytic evolution rate of 12.16 mmol g −1 h delivered nanosheets, far exceeding previously reported piezocatalysts photocatalysts. Further, high pure‐water‐splitting performance production value‐added oxidation product O via photo‐piezocatalysis also disclosed. This work not only exposes potential piezo‐semiconductor catalytic evolution, breaks new ground conversion solar photomediated

Language: Английский

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2D Graphitic Carbon Nitride for Energy Conversion and Storage

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(34)

Published: June 19, 2021

Abstract Graphitic carbon nitride (g‐C 3 N 4 ) have attracted great attention in the field of energy conversion and storage due to its unique layered structure, tunable bandgap, metal‐free characteristic, high physicochemical stability, easy accessibility. 2D g‐C nanosheets features short charge/mass transfer path, abundant reactive sites functionalization, which are beneficial optimizing their performance different fields. However, reviews comprehensive applications for rare. Herein, this review first introduces properties bulk nanosheets, then summarizes synthetic strategies detail, such as thermal oxidation etching, chemical exfoliation, ultrasonication‐assisted liquid phase vapor deposition, others. Emphasis is focused on rational design development diversified storage, including photocatalytic H 2 evolution, CO reduction, electrocatalytic O alkali‐metal ion batteries, lithium‐metal lithium–sulfur metal‐air supercapacitors. Finally, current challenges perspectives discussed.

Language: Английский

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Synergistic Polarization Engineering on Bulk and Surface for Boosting CO₂ Photoreduction

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(33), P. 18303 - 18308

Published: May 31, 2021

Abstract Sluggish charge kinetics and low CO 2 affinity seriously inhibit photoreduction. Herein, the synchronous promotion of separation Bi 4 Ti 3 O 12 is realized by coupling corona poling surface I‐grafting. Corona enhances ferroelectric polarization aligning domains direction, which profoundly promotes transfer along opposite directions across bulk. Surface I‐grafting forms a local electric field for further separating carriers provides abundant active sites to enhance adsorption. The two modifications cooperatively increase , maximize efficiency photogenerated charges, resulting in an enhanced production rate 15.1 μmol g −1 h (nearly 9 times) with no sacrificial agents or cocatalysts. This work discloses that ion grafting can promote photoreduction synergistic way.

Language: Английский

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Direct Z-scheme TiO2–ZnIn2S4 nanoflowers for cocatalyst-free photocatalytic water splitting

Applied Catalysis B Environment and Energy, Journal Year: 2021, Volume and Issue: 291, P. 120126 - 120126

Published: March 9, 2021

Language: Английский

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Designing covalent organic frameworks with Co-O4 atomic sites for efficient CO2 photoreduction

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Feb. 28, 2023

Abstract Cobalt coordinated covalent organic frameworks have attracted increasing interest in the field of CO 2 photoreduction to CO, owing their high electron affinity and predesigned structures. However, achieving conversion efficiency is challenging since most Co related coordination environments facilitate fast recombination photogenerated electron-hole pairs. Here, we design two kinds Co-COF catalysts with oxygen atoms find that after tuning environment, reported framework catalyst Co-O 4 sites exhibits a production rate 18000 µmol g −1 h selectivity as 95.7% under visible light irradiation. From in/ex-situ spectral characterizations theoretical calculations, it revealed significantly carrier migration matrixes inhibit pairs photocatalytic process. This work opens way for high-performance photoreduction.

Language: Английский

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g‐C₃N₄‐Based 2D/2D Composite Heterojunction Photocatalyst

Small Structures, Journal Year: 2021, Volume and Issue: 2(12)

Published: Sept. 16, 2021

Employing semiconductor photocatalysis to transform solar energy into chemical provides a practicable strategy for the alleviation of and environmental crisis. Graphitic carbon nitride (g‐C 3 N 4 ) is popular 2D photocatalyst with numerous advantages, such as visible light response, low cost, high stability. However, single g‐C displays poor performance due fast recombination photogenerated electrons holes. To improve this limitation, many research works have focused on construction ‐based 2D/2D heterojunction photocatalysts by hybridizing other materials. The intimate face‐to‐face contact in offers large area plentiful channels migration separation charge carriers. Furthermore, inherits strengths structure, including specific surface area, abundant adsorption sites active sites. Herein, preparation, mechanism, application are reviewed. Three common preparation methods summarized, solid phase reaction, situ growth, electrostatic self‐assembly. Various photocatalytic mechanisms discussed, traditional type‐II, Z‐scheme S‐scheme mechanisms. A series applications environment fields illustrated. Finally, future directions development proposed.

Language: Английский

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All-solid-state direct Z-scheme NiTiO₃/Cd_0.5Zn_0.5S heterostructures for photocatalytic hydrogen evolution with visible light

Journal of Materials Chemistry A, Journal Year: 2021, Volume and Issue: 9(16), P. 10270 - 10276

Published: Jan. 1, 2021

The construction of NiTiO3/Cd0.5Zn0.5S heterostructures is presented as all-solid-state direct Z-scheme photocatalysts for the efficient and stable hydrogen production under visible light. hybrids are assembled by growing Cd0.5Zn0.5S nanoparticles on surface NiTiO3 nanorods via a co-precipitation hydrothermal coupled method. compositional structural features composites fully disclosed diverse physicochemical characterizations. revealed to effectively capture optical spectrum in region well enhance transfer separation photogenerated charge carriers through Z-schematic pathway. Consequently, optimized photocatalyst shows high H2 rate 1058 μmol h−1 (26.45 mmol g−1), which independent any cocatalysts (such Pt), together with apparent quantum yield (AQY) 34% monochromatic light irradiation at 420 nm. Besides, also exhibit stability evolution photocatalysis mainly due fact that migration can enable consumption light-induced holes prevent photocorrosion effect. Finally, possible photocatalytic mechanism over based results band structures, density functional theory (DFT) calculations electron spin resonance (ESR) tests.

Language: Английский

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Role of transition metal oxides in g-C3N4-based heterojunctions for photocatalysis and supercapacitors

Journal of Energy Chemistry, Journal Year: 2021, Volume and Issue: 64, P. 214 - 235

Published: May 4, 2021

Language: Английский

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Exploring deep effects of atomic vacancies on activating CO2 photoreduction via rationally designing indium oxide photocatalysts

Chemical Engineering Journal, Journal Year: 2021, Volume and Issue: 422, P. 129888 - 129888

Published: April 22, 2021

Language: Английский

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