Chemical bonding interface in Bi2Sn2O7/BiOBr S-scheme heterojunction triggering efficient N2 photofixation

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 323, P. 122148 - 122148

Published: Nov. 7, 2022

Language: Английский

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ZnO with Controllable Oxygen Vacancies for Photocatalytic Nitrogen Oxide Removal

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(16), P. 10004 - 10017

Published: Aug. 2, 2022

Semiconductor-based photocatalysis is an ideal method for air purification by eliminating nitrogen oxide (NO). However, sluggish carrier separation, photocatalysts deactivation and incomplete oxidation are significant bottlenecks photocatalytic treatment of indoor pollutant NO. Herein, ZnO with assorted structures fabricated undergoes further modification deliberate surface defect constructions. Utilized flux agents during the synthesis provide a more feasible reducing atmosphere, under which spontaneous generations vacancies become easier, gradient concentrations precisely controlled. Photocatalyst characterizations affirm successful creation defects, evaluated solar-light-driven NO (ppb level) removal investigations. Results showed that rich in oxygen (VO-rich ZnO) exhibited 5.43 1.63 times enhanced fewer toxic product NO2 formations than its counterparts pristine VO-poor ZnO, respectively. Importantly, higher VO on unusual nonpolar facets, VO-rich does not only display conversion, but also shows unselective process producing NO3–. The plausible reaction mechanisms promoted conversions investigated based VO, well-positioned band structures, separations. facilitate molecular activation, leading to strong oxidant superoxide radicals (·O2–), contributing improved efficiency. Adsorption small molecules (O2, H2O NO) defective was density functional theory (DFT) calculations, validated adsorption/activation O2, contributed conversions.

Language: Английский

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Polarized Cu–Bi Site Pairs for Non‐Covalent to Covalent Interaction Tuning toward N₂ Photoreduction

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(37)

Published: July 21, 2022

A universal atomic layer confined doping strategy is developed to prepare Bi24 O31 Br10 materials incorporating isolated Cu atoms. The local polarization can be created along the CuOBi interface, which enables better electron delocalization for effective N2 activation. optimized Cu-Bi24 layers show 5.3× and 88.2× improved photocatalytic nitrogen fixation activity than bulk , respectively, with NH3 generation rate reaching 291.1 µmol g-1 h-1 in pure water. polarized Cu-Bi site pairs increase non-covalent interaction between catalyst's surface molecules, then further weaken covalent bond order NN. As a result, hydrogenation pathways altered from associative distal pathway alternating . This provides an accessible designing metal or tuning order.

Language: Английский

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Photo-Switchable Oxygen Vacancy as the Dynamic Active Site in the Photocatalytic NO Oxidation Reaction

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(22), P. 14015 - 14025

Published: Oct. 31, 2022

Identifying the dynamic structural changes of active sites in a catalytic reaction under realistic working conditions is great challenge. In this work, we demonstrate that situ electron paramagnetic resonance (EPR) technology an important technique for electronic-level recognition evolution over defective BiOCl catalyst during gas–solid photocatalytic reaction. The formation and recovery photoexcited oxygen vacancies (PE-OVs) with or without UV light irradiation are experimentally verified, these can be defined as photoswitchable OVs. OVs could function genuine to activate O2 molecules via directional single-electron transfer from px pz Bi 6p π2py* molecules. FT-IR spectra elucidate PE-OVs were available promote conversion intermediates final product. Thus, identified photocatalysis reactions, challenging common view static sites. This work provides innovative concept defects real catalysis reactions.

Language: Английский

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S-scheme Bi2O3/CdMoO4 hybrid with highly efficient charge separation for photocatalytic N2 fixation and tetracycline Degradation: Fabrication, catalytic Optimization, physicochemical studies

Separation and Purification Technology, Journal Year: 2023, Volume and Issue: 325, P. 124665 - 124665

Published: July 25, 2023

Language: Английский

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Recent advances in two-dimensional ultrathin Bi-based photocatalysts

Progress in Materials Science, Journal Year: 2022, Volume and Issue: 133, P. 101047 - 101047

Published: Nov. 26, 2022

Language: Английский

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Boosting Carrier Separation on a BiOBr/Bi₄O₅Br₂ Direct Z-Scheme Heterojunction for Superior Photocatalytic Nitrogen Fixation

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(8), P. 5779 - 5787

Published: April 1, 2024

Photocatalytic dinitrogen (N2) fixation is regarded as an achievable technology for ammonia (NH3) production. However, the poor separation efficiency of photoinduced carriers and ineffective N2 activation remain grand obstacles to high-performance NH3 photosynthesis. Designing advanced heterostructured systems accelerate charge activate molecule a feasible strategy optimize photocatalytic activity. Herein, direct Z-scheme configuration established between BiOBr Bi4O5Br2 through facile one-step solvothermal reaction. This enables effective spatial electron–hole pairs preserves robust redox ability carriers, concurrently promoting N≡N bond diminishing energy barrier rate-determining step. The formation BiOBr/Bi4O5Br2 heterojunctions mostly attributed similarities in their lattice structures crystal growth conditions. As result, heterojunction exhibits high yield 66.87 μmol g–1 h–1 without using sacrificing reagents, surpassing that pristine by approximately 3.3 5.6 times, respectively. study provides approach construct implementing under mild

Language: Английский

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Bi/BSO Heterojunctions via Vacancy Engineering for Efficient Photocatalytic Nitrogen Fixation

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(24)

Published: Feb. 19, 2024

Abstract Photocatalytic nitrogen reduction represents a viable technology for green ammonia synthesis under mild conditions. However, the performance of photocatalysts is typically limited by high charge carrier recombination and low adsorption activation molecules. Herein, Bi/Bi 2 Sn O 7 (Bi/BSO) heterojunction nanocomposites are prepared via one‐step hydrothermal method, where NaOH etching oxygen vacancies in Bi─O bonds Bi (BSO) exploited situ formation metallic hence Schottky junctions with semiconducting BSO. This leads to separation rate photogenerated carriers. Consequently, compared pure‐phase BSO, Bi/BSO heterostructures exhibit markedly enhanced production, reaching an optimum 284.5 µmol g −1 h , rectifying contact between BSO facilitates directional electron transfer, leading enrichment electrons at active sites Bi. First‐principles calculations confirm alteration guided flow surface vacancies. Results from this study offer effective paradigm structural engineering manipulating photocatalytic activity bismuth‐based pyrochlore materials toward fixation ammonia.

Language: Английский

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Visible Light‐Driven Conversion of Carbon‐Sequestrated Seawater into Stoichiometric CO and HClO with Nitrogen‐Doped BiOCl Atomic Layers

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(24)

Published: April 17, 2023

Seawater is one of the most important CO2 sequestration media for delivering value-added chemicals/fuels and active chlorine; however, this scenario plagued by sluggish reaction rates poor product selectivity. Herein, we first report synthesis nitrogen-doped BiOCl atomic layers to directly split carbon-sequestrated natural seawater (Yellow Sea, China) into stoichiometric CO (92.8 μmol h-1 ) HClO (83.2 under visible light with selectivities greater than 90 %. Photoelectrons enriched on exposed BiOCl{001} facet kinetically facilitate -to-CO reduction via surface-doped nitrogen bearing Lewis basicity. Photoholes, mainly located lateral facets van der Waals gaps, promote selective oxidation Cl- HClO. Sequestrated also maintains pH at around 4.2 prevent alkaline earth cations from precipitating. The produced can effectively kill typical bacteria in ballast water ocean-going cargo ships, offering a green safe way onsite sterilization.

Language: Английский

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Polar Layered Bismuth‐Rich Oxyhalide Piezoelectrics Bi₄O₅X₂ (XBr, I): Efficient Piezocatalytic Pure Water Splitting and Interlayer Anion‐Dependent Activity

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(29)

Published: March 31, 2023

Abstract Piezocatalytic pure water splitting for H 2 evolution carries the virtues of efficacious utilization mechanical energy, easy operation, and high value‐added products, while lacking desirable piezoelectrics chemical energy production. Here, two polar layered bismuth‐rich oxyhalides Bi 4 O 5 X (XBr, I) thin nanosheets (≈4 nm) are first exploited as efficient piezocatalysts to be capable dissociating water. The unique asymmetrical structures composed interleaved [Bi ] 2+ layer double − ions slabs along [1 0 1_] orientation cause large intrinsic dipole moment, excellent piezoelectricity deformation. Without any cocatalyst sacrificial agent, Br I display remarkable piezocatalytic production rate 1149.0 764.5 µmol g −1 h , respectively, standing among best piezocatalysts, accompanied by hydroxyl radicals (·OH) oxidative products. smaller radius higher electronegativity than a more strongly crystal structure in contributing activity compared . This study broadens scope piezoelectric materials applied sustainable catalysis efficiently converting illustrates importance configuration composition fabricating systems.

Language: Английский

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